ARMOR AND MATERIALS FOR COMBAT THREAT AND DAMAGE PROTECTION Gwynedd A. Thomas, Ph.D. Auburn University Polymer and Fiber Engineering Some DoD Projects (Dr.
Download ReportTranscript ARMOR AND MATERIALS FOR COMBAT THREAT AND DAMAGE PROTECTION Gwynedd A. Thomas, Ph.D. Auburn University Polymer and Fiber Engineering Some DoD Projects (Dr.
Slide 1
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
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M
m
F
M
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P
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ci
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ar
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ak
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m
m
m
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m
m
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re
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ag
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nu
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ar
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55.
M
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56
J
R
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si
an
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J
(M
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-1
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7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 2
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 3
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 4
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 5
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 6
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 7
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 8
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 9
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
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M
m
F
M
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LR
4
5
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P
JH
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12
11
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2
AC
P
ci
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32
ar
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8
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m
10
m
m
m
25
9
m
m
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FM
J
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ka
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re
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4
57
(S
M
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ag
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.2
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54
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as
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l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 10
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
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.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 11
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 12
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
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ag
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.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 13
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 14
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 15
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 16
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 17
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 18
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 19
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 20
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 21
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 22
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
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ar
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ar
7.
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62
ne
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R
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J
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62
Br
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7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 23
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
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M
ag
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nu
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ag
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54
C
as
ul
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l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 24
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 25
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 26
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 27
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 28
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 29
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 30
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 31
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 32
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 33
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
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m
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7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 34
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
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P
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ov
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m
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ak
38
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10
m
m
m
25
9
m
m
F
FM
J
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ka
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re
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ag
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nu
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ar
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70
56
J
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an
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62
Br
iti
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sh
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S
FM
P
7.
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62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 2
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 3
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 4
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 5
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 6
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 7
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 8
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 9
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 10
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
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M
m
F
M
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LR
4
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12
11
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ar
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m
m
m
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9
m
m
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57
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ag
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as
ul
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ar
7.
bi
62
ne
X
39
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F
55.
M
70
56
J
R
X
us
45
si
an
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J
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7.
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62
Br
iti
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sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 11
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
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ag
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as
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ar
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an
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7.
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62
Br
iti
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sh
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S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 12
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
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P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
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2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 13
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 14
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 15
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 16
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 17
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 18
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 19
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 20
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 21
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
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M
m
F
M
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12
11
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AC
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ci
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ar
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m
m
m
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9
m
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M
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ag
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as
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ar
7.
bi
62
ne
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55.
M
70
56
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R
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an
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J
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.3
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03
7.
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62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 22
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
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ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
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F
55.
M
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56
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us
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an
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J
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03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 23
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 24
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
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2
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ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 25
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 26
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 27
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 28
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 29
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 30
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 31
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 32
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 33
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
57
5
Si
g
m
0
J
J
.4
M
m
F
M
.4
C
P
LR
4
5
JH
P
JH
P
12
11
JH
P
2
AC
P
ci
al
A
.2
5
32
ar
ov
0.
Sp
e
.4
F
8
25
.3
x
m
m
.3
0
ak
38
M
0.
m
10
m
m
m
25
9
m
m
F
FM
J
To
ka
M
J
re
12
v
.3
4
57
(S
M
M
G
ag
)
nu
.4
m
4
JH
M
ag
P
nu
m
J
H
.2
P
2
M
ag
nu
m
.4
54
C
as
ul
.3
l
0
C
ar
7.
bi
62
ne
X
39
.4
F
55.
M
70
56
J
R
X
us
45
si
an
FM
J
(M
.3
-1
03
7.
6)
62
Br
iti
X
sh
51
S
FM
P
7.
J
62
(.
30
X
8)
63
(.3
006
)
.5
0
BM
G
7.
9
9
9
0.
Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)
Slide 34
ARMOR AND MATERIALS FOR COMBAT
THREAT AND DAMAGE PROTECTION
Gwynedd A. Thomas, Ph.D.
Auburn University
Polymer and Fiber Engineering
Some DoD Projects
(Dr. Gwen Thomas, P.I.)
1) US Army Aviation Applied Technology Directorate
(Comanche Project, 1998)
2) US Army ARDEC Picatinny Arsenal (LOSAT Kinetic
Energy Missile Protection, 2001)
3) US Army Air Warrior Program (Air Warrior Vest
Upgrade, Phases 1-3, 2002-2006)
4) US Navy NAVAIR (V-22 Osprey Internal Armor
Provision, current)
A.
B.
Army Research Lab follow-on (2009)
AFSOCOM, AFRL, USSOCOM follow-on (2010 ->)
5) ONR Roadside Bomb Protection (2010)
Modern Military Body Armor
• The FLAK jacket 19421970
• FLAK =
Fliegerabwehrkanone
(AAA)
– This armor was only
intended to stop shrapnel
Not intended for bullets
http://www.usmccollectibles.com/field%20gear.htm
Ballistic armor has 2 fields of application
Police and
government officials
Rated projectile
threats (handguns,
long guns)
Armor: light,
concealable, flexible
Military applications
Threats from
explosive device
fragments
High energy
projectile threats
(smg, rifle, mg)
http://www.berettausa.com/product/product_pistols_main.htm
http://op-for.com/v-22.jpg
62
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Energy Joules/cm2
Energy delivered by various
ammunitions
16000
14000
12000
10000
8000
6000
4000
2000
0
Projectile Type
Modern Protective Materials
• Fibers
– Very light
– Very limited
– Very flexible
• Ceramics
– Very strong
– Pretty light
– Really expensive!
• Metals
– Very strong
– Relatively cheap
– VERY heavy
Energy absorption in aramids
Tensile strength
23-28 gpd
Elongation to break
2.5 - 3.5 %
Young’s modulus
500 - 900 gpd
Specific gravity = 1.44
Fibrillates on impact
http://web.umr.edu/~wlf/Synthesis/kevlar.html
Energy absorption in HPPE
Tensile strength
30 - 40 gpd
Elongation to break
2.5 - 3.6 %
Young’s modulus
1400 - 2400 gpd
Specific gravity = 0.97
Usually uniaxially wrapped
and resin encased*
PIPD Fiber
• Poly{2,6-diimidazo[4,5-b4',5'-e]pyridinylene1,4(2,5-dihydroxy)phenylene}
• Commercial name “M5”
• Reputation as the upcoming Rock Star of
ballistic resistant fibers
• Tests by U.S. Army Natick Soldier Center
labs indicate very promising likelihood of
success in ballistic applications
• But there is little available right now
http://www.m5fiber.com/magellan/m5_fiber.htm
Ceramics
•
•
•
•
Aluminum oxide
Silicon Carbide
Boron carbide
Aluminum nitride
Aluminum oxide (Al2O3)
• Also known as alumina
• Naturally occurring ore of
aluminum
• High purity grades make
acceptable armor
• Spec. grav. = 3.7 - 3.9
• Less expensive than
other armor grade
ceramics
Is also the material of
http://en.wikipedia.org/wiki/Image:Corundum-unit-cell-3D-balls.png •
rubies and sapphires
Silicon carbide (SiC)
• Very rare in nature
– Found in meteorites
• Very effective in body armor
and
• Chobham armor
• Much more expensive than
alumina
• Spec. grav. = 3.1-3.22
• Hardness = 2800 kg/mm2
http://en.wikipedia.org/wiki/Image:Silicon-carbide-3D-balls.png
Boron carbide (B4C)
• Third hardest known
material
– Diamond = 1
– Cubic boron nitride = 2
• Spec. grav. ~ 2.5
• Extremely effective in
armor
• Very expensive
• Hardness = 2900 3550 kg/mm2
http://www.csj.jp/journals/chem-lett/cl-cont/c00jun_gif/00060662ga.gif
Aluminum Oxynitride (AlON)
• “Transparent aluminum”
or “transparent ceramic”
• Spec. grav. 3.69
• Superior to glass and
Lexan in transparent
armor
– Scratch resistant
– Defeats .50 cal AP
• Very expensive ($10$15/ square inch!)
• Hardness=1850 kg/mm2
Fragment defense – nonwoven
approach
Strong weight advantages for
nonwoven fabrics over woven
fabrics (8+lbs)
Initial commercial introduction of
100% HPPE nonwoven - DSM
“Fraglight”, 1995
Initial suggestion of blended
nonwoven fabrics
Nonwovens allow a great deal of moisture and heat transport
compared to tight weaves. This nonwoven does not require
plastic resin coatings.
Fiber blend nonwoven
100% Kevlar nonwoven
Thomas and Thompson,
Techtextil 1992
Cordova, Kirkland et al 1994
(TechTextil Frankfurt, Thomas and Thompson)
Energy absorption in
HPPE/Aramid fiber blends
Radiated strain energy
Transferred by aramid and
HPPE beyond impact area
Fibrillation of aramids
But fabric network integrity
preserved by non-malleable
character of aramid
Phase change induced in
the thermoplastic HPPE
Resulted in a 30% increase in
performance over the
predicted force dissipation
behavior
Tests performed at DuPont labs, Wilmington, DE
Fragment armor improvements with
nonwoven technology
• Results from US Army
Aberdeen Proving Grounds
test
V 50 For Valid Weight Candidates
• .22 cal. 1.10 gram,
fragment simulating
projectile, steel
540
520
• Parameters :
• Nonwoven materials were
superior to woven aramid
and woven PBO
• Historical development of
nonwoven armor-
• Original Kevlar 29 = 389
m/sec
• Original (1991) blend
yielded 434 m/sec (HPPE,
2nd quality and Kevlar 29)
Meters/Second
• Weight < 3.42 kg/m2
• Projectile speed > 425
m/sec (1400fps)
500
480
460
440
448
477
462
495
531
420
400
Twaro
n .69
lbs/ft2
Zylon
PB O
.53 lb
s /ft2
Armo
r
Felt M
.50 lb
s/ft2
Armo
r
Felt1
.54 lb
s
Armo
r
/ft2
Fabric Type
* Test results 31 August – 1 September 2002
Felt M
.71 lb
s/ft2
Results of V50 testing, 0.13 gram
(2 grain) RCC FSP
0.13 gm RCC V50
Meters per S econd
1100
1069
1000
1074
1074
Army Specification = 1005m/sec
900
(3x3)
(4x4)
Results pairings
(5x5)
Results of V50 testing, 0.26 gram
(4 grain) RCC FSP
0.26 Gram RCC V50
1000
Meters per S econd
900
963
963
961
Army Specification = 823 m/sec
800
700
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 1.0 gram
(16 grain) RCC FSP
1.0 Gram RCC V50
Meters per S econd
800
760
762
764
700
Army Specification = 678 m/sec
600
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 4.15 gram
(64 grain) RCC FSP
4.15 Gram RCC V50
700
Meters per S econd
650
600
639
550
640
640
Army Specification = 556 m/sec
500
(3x3)
(4x4)
Group Pairings
(5x5)
Results of V50 testing, 9 mm, 8.0
gram (124 grain) FMJ
9 MM V50
600
Meters Per Second
550
582
581
582
500
450
Army Specification = 457 m/sec
400
(3x3)
(4x4)
Group Pairings
(5x5)
US Marines Test Results
I.E.D.’s
2.2lbs/ft2 sample, range 15 meters
•
Nine fragments impacted the sample
panel
–
–
•
One of the large fragments, penetrated
three ArmorFelt and 14 aramid layers
–
•
•
No complete penetration.
3 large (50-150 grain) fragments impacted
the panel along with six smaller (50 grain or
less) fragments.
(out of 3 layers of ArmorFelt, 40 layers of
Kevlar, 3 layers of ArmorFelt)
No other large fragments, penetrated
deeper than three ArmorFelt layers
None of the fragments completely
penetrated the armor.
2 December 2003
US Marines Test Results
I.E.D.’s (cont)
2.2lbs/ft2 sample, range 5 meters
•
22 fragments impacted the
sample panel
–
–
•
Only one of the two large
fragments, completely
penetrated the armor
–
•
1 complete penetration.
2 large (50-150 grain) fragments
impacted the panel along with
twenty smaller (50 grain or less)
fragments.
(3 layers of ArmorFelt, 40 layers
of Kevlar, 3 layers of ArmorFelt)
None of the smaller fragments
penetrated the armor.
2 December 2003
US Marines Test Results
Hand Grenades
•
•
Tests performed at Quantico, VA
2 samples tested
– A) Identical to Auburn AW design
– B) Heavier than Auburn AW design
•
M-67 hand grenade
– One detonation each target from 4
feet range
•
Results
– A) No penetrations on Auburn AW
design type
• 22 hits by fragments
– B) 1 penetration on heavier type
• 17 hits by fragments
November 2003
Test conducted under guidance of Maj. A.J. Butler,
USMC (ret)
Levels III and IV
Very high energy projectiles
7.62 x 51 FMJ (.308)
State of the Art
• SAPI
– Small Arms
Protective Insert
• Based on Boron or
Silicon Carbide
• Backing made of
aramid or HPPE
composites
http://en.wikipedia.org/wiki/Image:Sapi_plates.jpg
ESAPI
• Enhanced Small Arms
Protective Insert
• Permits protection
against armor
penetrating bullets
• Was needed protection
beginning 2003
http://www.marcorsyscom.usmc.mil/SITES/PMICE/Images/Armor&Load/ESAPI.jpg
Ceramic or metal plate armor
spall
As the projectile
penetrates the
armor
fragmentation
(shatter) occurs
momentum is
transferred to the
particles
a spall cloud forms
Vspall =
2 E a(m p m a ) C d A /m
Initial penetration
Spall fragment cloud
US Army, ARL Website
http://www.arl.mil
p
• ma
Armor piercing projectiles
Most serious threat to
military personnel with
body armor
May use either
hardened steel or
tungsten carbide
Designed as
multicomponent (eg)
copper sheath
lead tip (spall generator)
carbon steel interior
Graphic courtesy of Jeff Simon, SRI International
One solution to this problem Stop the bullets by inducing chaos
A trajectory is a highly ordered kinetic path
Targets are destroyed by release of the
kinetic energy where the projectile is
aimed
Destabilization can result in degradation of
lethality, kinetic energy transfer
A flexible hard armor media
Generation of multiple
simultaneous paths
Projectile spreads,
fragments
Spall cloud redirected
by internal geometrics
Fragment defense by
nonwovens
Deflecting geometrical surfaces
Embedded hard elements in
flexible media
Graphic courtesy of Jeff Simon, SRI International
US Patent # 5,736,474, “Multistructure Ballistic Material”, Auburn University
Thomas., 1997
Projectile Impact Sequence
How the new armor works:
In the initial stages of the impact, the projectile enters the vest in the
normal manner, with standard ballistic resistant fabrics or thin, high
strength ceramic plates distorting the leading end and increasing the
projectile drag as it enters.
Upon entry into the geometrics zone, the projectile is turned by the
deflecting surfaces.
As it continues along the path, the initially turned leading end is
deflected into other paths while the trailing end has not yet experienced
the torquing action of the shock waves in the projectile body.
The front portion begins to disintegrate, clearing the way for the rear
section to be deflected along similar reverse torqued paths until the
projectile is finally totally destroyed and comes to rest in the geometric
layer.
In initial tests with this media, both 7.62x39 mm Russian and .30-06 US
rifle ammunition have been destroyed at 15 meters distance and less
without the use of ceramic front plate facings on the armor package.
Both ammunition types were destroyed in multi hit test conditions.
ChaoTech:
Hard armor media
Generation of multiple
simultaneous paths
Projectile spreads, fragments
Spall cloud redirected by
internal geometrics
Fragment defense by
ArmorFelt
Multiple materials available
7.62x39 API
(6 hits)
.30-06 APM2
(5 hits)
ChaoTech reduces the weight
of any armor material
12.7 mm API
(All projectiles impacted at full muzzle velocities)