Transcript Marine/Composites research opportunities

Composite materials
Composite materials
John Summerscales
Advanced Composites Manufacturing Centre
School of Marine Science and Engineering
University of Plymouth
1
Composites materials
Newton’s second law of motion
• Force = mass x acceleration (F = ma)
• reduce mass
• same performance with smaller engine, or
• improved performance with the same engine
• relative densities (vs water at 1000 kg/m3)
•
•
•
•
8000
2700
2000
1500
steel
aluminium
glass fibre reinforced plastics
carbon fibre reinforced plastics
2
Composites materials
Materials
• fibres
• aramid: orange light tough (e,g, Kevlar)
• carbon: black
stiff brittle expensive conductor
• glass: transparent
tough inexpensive
• polymers
• thermoplastics: heat-form-cool
• thermosets: liquid reactive mixture
3
Composites materials
Basic rule-of-mixtures 1
• Elastic properties (e.g. density or modulus) of
composite calculated by rule-of-mixtures
• EC = ηL . ηO . Vf . Ef + Vm . Em
• if the first term of the equation is large,
the second term can be neglected
Composites materials
Basic rule-of-mixtures 2
•
•
•
•
•
•
E = modulus of composite
η = fibre length distribution factor
η = fibre orientation distribution factor
V = volume fraction of component x
E = modulus of component x
subscripts f and m are
fibre and matrix respectively
C
L
O
x
x
Composites materials
Basic rule-of-mixtures 3
ηL = fibre length distribution factor
• 1 for continuous fibres
• fractional for long fibres
• 0 if fibre below a “critical length”
Composites materials
Variation of E with fibre length:
fibre length distribution factor ηl
• Cox shear-lag
• depends on
•
•
•
•
•
•
Gm: matrix modulus
Af: fibre CSA
Ef: fibre modulus
L: fibre length
R: fibre separation
Rf: fibre radius
< Tension
< Shear
Composites materials
Basic rule-of-mixtures 4
ηO = fibre orientation distribution
factor
• a weighted function of fibre
alignment,
essentially cos4θ:
•
•
•
•
1 for unidirectional
1/2 for biaxial aligned with the stress
3/8 for random in-plane
1/4 for biaxial fabric on the bias angle
Variation of E with angle:
Composites materials
fibre orientation distribution factor ηo
Composites materials
Basic rule-of-mixtures 5
• Vf = fibre volume fraction
• 0.15-0.3 for random
• 0.35-0.6 for fabrics
• 0.6-0.75 for unidirectional
• consolidation pressure:
• no pressure gives low value
above
• V increases with pressure
Composites materials
Basic rule-of-mixtures 6
• Ef = elastic modulus of fibre
• glass = ~70 GPa
(equivalent to aluminium)
• aramid = ~140 GPa
• carbon = ~210 GPa
(equivalent to steel)
• figures above are lowest values
i.e. for standard fibres
Composites materials
Glass transition
temperature (Tg)
• Tm = crystalline melting point
• Temperature at which
segmental motion of the chain is frozen out
• below Tg polymer is elastic/brittle
• above Tg polymer is viscoelastic/tough
• more rigorous than heat distortion temperature
• Tg for thermoplastics = Tm - ~200°C
• Tg for thermosets follows cure temp.
Composites materials
Matrix cracking
max
•
•
•
•
polyester resin ε’ = 0.9-4.0 %
vinyl ester
ε’ = 1.0-4.0 %
epoxy resin
ε’ = 1.0-3.5 %
phenolic resin ε’ = 0.5-1.0 %
•
data from NL Hancox, Fibre Composite Hybrid Materials, Elsevier, 1981.
min
Composites materials
Fibre fracture
•
•
•
•
•
S/R-glass
E-glass
Kevlar 49
HS-carbon
UHM-carbon
ε’ = 4.6-5.2 % ….
ε’ = 3.37 % ……….…
ε’ = 2.5 % …….……….
ε’ = 1.12 % ……………..…
ε’ = 0.38 % ………………….
•
data from NL Hancox,
Fibre Composite Hybrid Materials, Elsevier, 1981.
Composites materials
Fibre-matrix debonding
a
b
c
• Crack can run
through (not shown), or
around the fibre
• NB: ~12000 carbon or 1600 glass UD fibres/mm2
Composites materials
Fibre-matrix debonding:
Composites materials
Delamination of layers
• one layer is a lamina (plural = laminae)
• several layers in a composite is a laminate
• separation of the layers is delamination
• to avoid delamination
• 3-D reinforcement (often woven or stitched)
• Z-pinning
Composites materials
Fibre pullout
• as parts of a fractured composite separate,
the fibres which have debonded can fracture
remote from principal fracture plane.
• energy is absorbed by frictional forces
as the fibre is pulled from the opposite face
• debonding and pullout absorbs high energies
and results in a tough material
Composites materials
Marine Composites: state-of-the-art
• Swedish Navy Visby stealth corvette
• 600 tons - 72 m long - FRP sandwich
• Royal Navy mine counter measures vessels
• 725 tons - 60 m long - monolithic GRP
19
Composites materials
Marine Composites: state-of-the-art
• VT Mirabella V sloop rigged yacht
• 740 tonnes - 75.2 m long - 90 m mast
• CFRP/GRP/polyolefin foam
20
Composites materials
Marine leisure
• Power-boats: racing/“gin palaces”
• Sailing: ocean racing thro’ boating lake
• Diving: wet-suits and air-tanks
• EnvironComp (Halmatic GFRPP boat)
• EU BE-3152 : BRPR-CT96-0228
• Research, development and evaluation of
environmentally friendly advanced
thermoplastic composites for the manufacture
of large surface area structures
21
Composites materials
Formula 1
• http://www.mclaren.co.uk/
•
http://ourworld.compuserve.com/homepages/john_hopkinson/williams.htm
22
Composites materials
Road cars
• McLaren F1 road car
http://www.cottingham.co.uk/macf1/road.htm
23
Composites materials
Road cars
• Lotus Elise S2
• Reliant Robin 65 (2000)
24
Composites materials
Caparo Freestream T1
Graham Halstead
UoP composites graduate –
now with McLaren Racing
25
Composites materials
Dimitris Katsanis
• BEng CME graduate (project & Olympics)
26
Composites materials
Railways
• Inter-City 125 locomotive cab
http://home-2.worldonline.nl/~fgvdhurk/hst.htm
27
Composites materials
Aircraft specifications
Boeing 737
Concorde
Airbus A380
(189)
100
555
Length
38.4 m
62.1 m
73 m
Wingspan
28.9 m
25.6 m
79.8 m
Height
11.1 m
11.4 m
24.1 m
125 tonnes
185 tonnes
560 tonnes
Passengers
T/O weight
28
Composite materials
Aerospace: Airbus A380
The world’s only twin-deck, four-aisle airliner
The airlines’ solution to growing demand for air travel
The green giant, more fuel-efficient than your car
The dedicated three-deck 150 tonne long-range freighter
29
Composites materials
Aerospace: defence
• Joint Strike Fighter (F-35)
30
Composites materials
Biomimetics
http://www.rarebirdphotography.co.uk
Common Tern
Ivory Gull
Squacco
Stone Curlew
31
Composites materials
Aerospace: defence
• Grumman X-29 FSW aircraft 1984 to 1992
http://www.globalsecurity.org/military/systems/aircraft/x-29.htm
32
Composites materials
Wind energy
Vestas Blades UK Limited
(formerly NEG-Micon )
Isle of Wight
wind turbine blades up to 42 m
developed with ACMC Plymouth
33
Composites materials
Key features:
offshore wind farm
• Middelgrunden
• windfarm length of 3.4 km near Copenhagen, Denmark
• 20 turbines, each 2 MW
• 60 m hub height, 76 m rotor diameter.
• water depth of 2-6 metres
• modified corrosion protection,
internal climate control, built-in service cranes.
• 85 000 MWh pa (3% Copenhagen's needs)
• construction March 2000 to March 2001
•
http://www.worldenergy.org/wec-geis/publications/reports/ser/wind/wind.asp
34
Composites materials
Rehabilitation of civil
engineering structures
• London Underground tunnels
35
Composites materials
Bridge structures
• Aberfeldy footbridge over River Tay
36
Composites materials
Internet resource for composites
Teaching support materials for MATS324
Composites design and manufacture:
http://www.tech.plym.ac.uk/sme/mats324
Case studies: offshore structures, naval
vessels, yacht hulls, canoes, sailcloth.
http://www.tech.plym.ac.uk/sme/composites/marine.htm
Case studies: bridges
http://www.tech.plym.ac.uk/sme/composites/bridges.htm
37
Composites materials
BEng Mechanical Engineering with Composites
•
•
•
•
Year 1 common with Mech Eng/Marine Tech
Year 2 common with Mech Eng
Year 3 in industry ?
Year 4: 40 credits for composites pathway
• composites design and manufacture (20 credits)
• selection, characterisation, stress analysis & manufacture
• composites engineering (20 credits practical)
• mountain bike suspension/bike front forks
• yacht winch handle
• skaters trolley/dinghy launching trolley
38
Composites materials
Composites graduate destinations
• Aerospace
• Air France, Airbus (UK & F), BAe, GKN etc
• Formula 1
• Benetton, McLaren, Team Toyota, Williams
• Automotive
• Aston Martin Lagonda, BMW (D),
• Pininfarina (D), TWR Leafield
• Marine
• Carbospars (ES), Princess, Sunseeker
39
Composites materials
To contact me
 Dr John Summerscales
 Reynolds Building Room 008
 01752.5.86150
 07753.56.8733
 01752.5.86101
 [email protected]
 http://www.plym.ac.uk/staff/jsummerscales
40