Transcript Cr-Al-N film deposited with rotation system

THE DEVELOPMENT OF A SURFACE
ENGINEERED COATING SYSTEM FOR
ALUMINUM PRESSURE DIE CASTING DIES:
TOWARDS A ‘SMART’ DIE COATING
Advanced Coatings and Surface Engineering Laboratory
(ACSEL)
Colorado School of Mines
Jianliang Lin, Sterling Meyers, Brajendra Mishra, Sudipta Bhattacharyya,
Peter Ried,, John J. Moore
Acknowledgements: NADCA/DOE
•Premier Tool & Die Cast, SPX Contech, GM Powertrain, H-L, Leggett and Platt, St. Clair
•Balzers, Hardchrome, Ion Bond, Phygen, Teer Coatings
Methodology
Determine the most promising
working layer
- Sessile drop
- Soldering (DSC)
- Ease of release
- Tribological
- In-plant trial
test
Work done by K.Kearn, O. Salas, A. Kunrath, J.Lin
Design an optimal coating
architecture by FEM
in-plane stress (Pa)
“working layer”
3.50E+08
Graded
interlayer
3.00E+08
2.50E+08
2.00E+08
18
H13
50 nm adhesion layer
20
22
Work done by
S.Carrera
24
distance (microns)
Develop the optimized coating
architecture by P-CFUBMS
Field and Service testing
- Multimode tester
- Coating degradation
- Soldering (DSC)
- Ease of release
J. Lin & S. Myers is working on this
Optimized Coating System
(Al,Cr)2O3
Steps to the goal:
Deposition of CrN and
AlN binary phase
Deposition of CrAlN
CrxAl1-xN
Multilayer or
Compositionally graded
CrN
Deposition of (Al,Cr)2O3
working layer
Cr (60-100nm)
Deopsition of CrN/CrAlN
graded layer
H13 die substrate
Deposition of the overall
optimized coating architecture
Overall coating thickness is about 5-8 m
Plasma nitrocarburized
Cr-Al-N film Deposition Using P-CFUBMS
• Optimize the substrate to chamber wall distance
(fixed substrate position)
• Deposit CrAlN film with rotation system
• Optimize the working pressure and N2 partial
pressure
• Optimize the Al concentration in CrAlN films
Cr-Al-N films deposited at different substrate to
chamber wall distances
Cr
Al
Pulsed closed field unbalanced magnetron sputtering system
The ion energy in the plasma is
different at different substrate
positions
GIXRD results
1000W Cr-1100W Al  20 at% Al in film
2 m T o rr, 1 0 0 0 W /1 1 0 0 W , 7 5 :2 5 , -5 0 V b ia s , d iffe re n t s u b s tra te p o s itio n
200
700
650
111
600
400
220
550
500
( 5 in c h e s )
450
Intensity
400
350
( 6 in c h e s )
300
250
200
(7 in c h e s )
150
100
50
(8 in c h e s )
0
20
40
60
2 T h e ta (D e g re e )
80
100
All Cubic
Nano-hardness and Young’s Modulus
400
50
45
350
300
35
30
250
25
200
20
15
150
Y o u n g 's M o d u lu s
10
100
H a rd n e ss
5
50
0
4.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
8.0
)
r) d(%
N b2 (N
(inches)
istance
er 2 +wAall
Sub strate to cham
8.5
9.0
Y o u n g 's M o d u lu s (G P a )
H a rd n e s s (G P a )
40
Ball-on-disk test and coefficient of friction
0.7
C O F v.s S T D
0.60
0.55
C o e ffic ie n t o f F ric tio n
F ric tio n o f C o e ffic ie n t
0.6
0.5
0.4
0.50
0.45
0.40
0.35
0.30
0.3
5
7
8
S ubstrate to cham ber w all distance (inches)
5 inches
0.2
6
6 inches
Ball on disk wear test:
• Micro-tribometer
7 inches
0.1
8 inches
9 inches
• Counter part: 1mm WC ball
0.0
0
1000
2000
3000
T im e (seconds)
4000
5000
6000
• Applied force: 3N
• Travel length: 100m
9
Photomicrographs of wear tracks
after 100m travel
5 inches
6 inches
8 inches
9 inches
7 inches
Wear volume and wear factor of Cr-Al-N films
3D profile of the wear track
3
factor ( mm / Nm ) 
Wear volume ( mm )
3
wear
Load ( N )  Travel length ( m )
18
W e a r F a c to r
16
3
mm )
-1
-1
mm N M )
W e a r V o lu m e
14
W e a r V o lu m e (1 0
10
-7
W e a r F a cto r (1 0
2D profile of the wear track
-3
3
12
8
6
4
2
0
4
5
6
7
8
9
S u b stra te to C h a m b e r W a ll D isa n ce (In ch e s)
10
Ion energy distribution (IED) of N(29) in plasma
1 0 0 0 W , p u ls in g b o th ta rg e ts a t 3 5 0 K h z, 1 .4 u s , 2 m to rr, 7 5 :2 5
1600000
8 inc he s
4 inc he s
1400000
S E M C /S
1200000
1000000
800000
600000
400000
200000
0
0
20
40
60
80
100
E n e rg y (e V )
120
140
160
SEM photomicrographs at cross-section of Cr-Al-N films
1000W Cr-1100W Al pulsing both 100kHz at 1 s
5 inches
7 inches
6 inches
8 inches
Cr-Al-N film Deposition Using P-CFUBMS
• Optimize the substrate to chamber wall distance
(fixed substrate position)
• Deposit Cr-Al-N film with rotation system
• Optimize the working pressure and N2 partial
pressure
• Optimize the Al concentration in CrAlN films
Cr-Al-N film deposited with rotation system
• Deposition parameters:
• Total Pressure: 2mTorr; N2:Ar = 75:25
• 1000W to Cr target, 1100W to Al target
Cr
• -50V substrate bias
• Planetary rotation system with substrate
to chamber wall distance ~ 4.5 inches
2m torr, 1000W /1100W , -50V bias, 75:25
Al
400
350
300
200
250
220
In te n s ity
• To avoid the formation of superlattice
structure, the minimum rotation linear
speed is 10 cm/sec, which was
calculated from the system geometry
and deposition rates
111
W ith rotation
200
150
400
100
• Rotation linear speed used: ~ 12 cm/sec
Fixed @ 7"
50
0
20
30
40
50
60
2-T heta
70
80
90
100
Cr-Al-N film deposited with rotation system
50
400
45
W ith R o ta tio n
350
Ra=7.01nm
300
35
30
250
25
200
20
150
15
Y o u n g 's M o d u lu s
10
100
H a rd n e ss
5
Y o u n g 's M o d u lu s (G P a )
Ra=30.33nm
H a rd n e s s (G P a )
40
50
0
4 .0
4 .5
5 .0
5 .5
6 .0
6 .5
7 .0
7 .5
8 .0
8 .5
9 .0
S u b stra te to ch a m b e r w a ll d ista n ce (in ch e s)
The mechanical properties and surface roughness of Cr-AlN film deposited with rotation system can be compared
with those films deposited at fixed far positions
Ra=28.67nm
Cr-Al-N film Deposition Using P-CFUBMS
• Optimize the substrate to chamber wall distance
(fixed substrate position)
• Deposit CrAlN film with rotation system
• Optimize the working pressure and N2 partial
pressure
• Optimize the Al concentration in CrAlN films
Optimized working pressure and N2 partial pressure
34
35
7 5 :2 5 , 1 0 0 0 /1 1 0 0 w , -5 0 V b ia s, 1 h r d e p o sitio n
2 m to rr, 1 0 0 0 /1 1 0 0 w , -5 0 V b ia s, a t 7 in ch e s
32
3 m to rr, 1 0 0 0 /1 1 0 0 w , -5 0 V b ia s, a t 7 in ch e s
30
30
H a rd n e ss (G P a )
H a rd n e ss (G P a )
28
25
20
15
26
24
22
20
18
16
14
12
10
1 .5
2 .0
2 .5
3 .0
3 .5
W o rk in g p re ssu re (M to rr)
4 .0
50
55
60
65
N 2 ra tio (% )
The optimized working pressure is 2 mtorr and N2 partial pressure is 75%
70
75
80
Cr-Al-N Films Deposited at 2mTorr with –50V Substrate Bias
pN2=1 mTorr, 50% N2
pN2=1.2 mTorr, 60% N2
2 m
pN2=1.6 mTorr, 80% N2
P N2=1.5 mTorr, 75% N2
Decreased deposition rates
Cr-Al-N film Deposition Using P-CFUBMS
• Optimize the substrate to chamber wall distance
(fixed substrate position)
• Deposit CrAlN film with rotation system
• Optimize the working pressure and N2 partial
pressure
• Optimize the Al concentration in CrAlN films
P-CFUBMS Deposition Matrix
(Al,Cr)2O3
Multilayer or
Compositionally
graded
Increasing Al
content in the
intermediate
layer
Cr
target
power
(W)
Al
target
power
(W)
Al/Cr
target
power
ratio
400
400
1
400
600
1.5
400
800
2
400
1000
2.5
400
1200
3
Working
distance
(inches)
8
CrxAl1-xN or
TixAl1-xN
X=?
400
1400
3.5
200
800
4
200
1000
5
200
1200
6
200
1400
7
Working
pressure
(mtorr)
2
N2:Ar
Bias
(V)
75:25
-50
Optimized in previous work
XPS of Cr-Al-N films
Survey spectrum results:
Al:Cr target power ratio
C
Ar
O
Al
Cr
N
Al/(Al+Cr)
1
11.4
1.5
10.6
5.8
35.9
34.8
13.9 at%
3.5
7.1
1.7
10.0
18.5
22.3
40.3
45.3 at%
6
4.5
2.1
10.3
20.1
19.1
44.0
51 at%
7
3.8
2.2
10.4
21.3
16.7
45.6
58 at%
AlN 74.2eV
CrN 584.8eV and 575.4eV
CrN/AlN 397eV
Al2O3 75.2eV
Cr 2p photoelectron spectra
Al 2p photoelectron spectra
All samples exhibit similar Cr 2p, Al 2p, N 1s high energy spectra
N 1s photoelectron spectra
Optimize Al contents in Cr-Al-N films
G IX R D o f C rA lN film s d e p o s ite d a t:
C (2 0 0 )
d iffe re n t C r:A l ta rg e t ra tio (p u ls in g a t 1 0 0 K H z, 1 .0 u s )
C (1 1 1 )
600
2 m to rr, 7 5 % N 2 , -5 0 V b ia s , 2 h o u rs d e p o s itio n
H (1 0 0 )
C (2 2 0 )
Al:Cr
C
r : Atarget
l ta rg eratio
t p o w e r ra tio
7
Hexagonal phase appeared
400
6
Intensity
58
51
5
200
3 .5
45.3
1 .5
0
20
30
40
50
2 -T h e ta
60
70
Al/(Al+Cr)
Lattice parameter change
C rN
L a ttice p a ra m e te r (n m )
0.414
Lattice param eter v.s A l contents in C r-A l-N film s
0.412
0.410
13.9% A l
51% A l
0.408
58% A l
45% A l
0.406
H exagonal+ C ubic
C ubic
0.404
0
1
2
3
4
5
A l/C r ta rg e t p o w e r ra tio
6
7
Nano-harness and Young’s Modulus of Cr-Al-N
films
50
500
Y o u n g 's M o d u lu s
N a n o h a rd n e s s
45
300
30
45.3at%
25
200
58at%
51at%
20
13.9at%
Higher H/E ratio indicates good wear
resistance and good toughness
0.096
H exagona+ cubic
C ubic
0.094
15
100
0
1
2
3
4
5
6
7
8
0.092
hexagonal
45.3at% A l
A l /C r ta rg e t p o w e rra tio
0.090
The highest hardness is about 36GPa
H /E ra tio
H a rd n e ss (G P a )
35
Y o u n g 's M o d u lu s (G P a )
400
40
0.088
cubic cubic+ hex
0.086
51at% A l
0.084
58at% A l
0.082
13.9at% A l
0.080
1
2
3
4
5
A l/C r ta rg e t p o w e r ra tio
6
7
Wear resistance and COF
0 .6 0
0.50
0 .5 5
0.48
0 .5 0
0.46
C O F of C r-Al-N film s at different Al contents
13.9at% Al
0 .4 5
A l/C r ta rg e t
0 .4 0
p o w e r ra tio
1
0 .3 5
2
2 .5
0 .3 0
3
3 .5
0 .2 5
4
0 .2 0
C o e ffic ie n t o f F ric tio n
C o e fficie n t o f F rictio n
58at%
51at%
0.44
0.42
0.40
0.38
45.3at% Al
0.36
0.34
5
1
6
0 .1 5
0 .1 0
1000
2000
3000
T im e (m in s)
4000
5000
3
4
5
6
Al/C r target power ratio
7
0
2
6000
Ball-on-Disk wear test:
• Micro-tribometer
• Normal load: 3N
• Counterpart: 1mm WC ball
• Travel length: 100m
7
Summary of P-CFUBMS of Cr-Al-N films
• An Optimized coating ‘architecture’ used for Al pressure die
casting dies has been proposed
• Cr-Al-N intermediate layer with good mechanical properties
and dense microstructure has been successfully deposited.
• Deposition of Cr-Al-N coatings with a planetary rotation
system has been successfully demonstrated.
• The critical Al concentration in the Cr-Al-N coatings has been
determined.
• On-going work:
– Deposition of the (Al,Cr)2O3 working layer
– Deposition of the compositionally-graded Cr-Al-N intermediate layer
1st In-Plant Trial Pins: Premier Tool & Die
Shots / Cycles (n)
2nd In-Plant Trial Pins: Leggett & Platt
Selected Core Pins
1n
2n
3n
100% of Typical pin life
•After each trial, half of pins:
Dissolved in NaOH/Industrial Degreaser and characterized using Stereography and SEM
Removing lubricant and Al from pins quite painstaking.
Typical removal times at least 3 weeks in ultra-sonicator.
•Other half of in-plant trial pins
No dissolving
Cross-x cut and prepared for metallographic & SEM characterization
Becoming quite difficult due to coating removal while performing metallographic prep work
In-Plant Trial Pins
New Pins
¼ ins
Same Pin; Lubricant Removed
Conclusion: Pin after 10k shots contains no visible defects
Preliminary Results
•Stereographic Results
•CrN, CrC-TiAlN
coatings show few signs
of wear
• TiN-TiAlN, Cr/TiNTiAlN illustrate more
signs of wear
•FeNC surface treatment
show most signs of wear
and soldering
SEM Results
•Data still not produced
•Edge retention of
coating lost during
metallography
‘Ease of Release’ Test
One can measure the adhesion/soldering strength of the pin by
separating the pin and solidified Al using a tensile testing machine with
a calibrated load cell
The pin must be pulled perpendicular to the solidified Al axis to assure
same stress levels
Load/time curves – ‘ease of release’ test
Load (lb)
‘critical load’ (Lc)
5500
5000
4500 3
4000
3500
3000
2500
2000
1500
1000
500
0
0
6
1
2
3
4
5
6
CFUBMS-TiN/TiAlN m (Lc 2468lb)
MS-CrC/TiAlN (Lc 3937lb)
CFUBMS-MoZrN (Lc 4025lb)
MS-CrN (Lc 2371lb)
CAE-graded CrN (Lc 1456lb)
FeNC (Lc 5298lb)
2
1
4
10
5
20
30
40
Time (second)
50
60
Experimental program: ease of release tests
Control
ACSEL
ACSEL
G-Cr/N
CrCTiAlN
MLTiN/TiAlN
Plain
3
3
3
3
3
3
FeCN
3
3
3
3
3
3
Ionnitrided
3
3
3
3
3
3
‘Smart’ die coating: experimental architecture
Working layer
Intermediate layer (TiAlN)
Ti/Cr
Stress
(out of plane)
Adhesion layer
Die steel
Surface modification
substrate
of the substrate
Sensor module
Thin-film
Electrodes
(Sputtered Ti)
Piezo. Film
(in-plane)
V3(Sensor voltage)
Non piezoelectric
Insulation layer
3
1
2
Stress
V 3  E 3 .d   1, 2 e 31 , f .d
(d= thickness)
Choice of active sensor material
Requirements:
Figure of Merits
PZT
AlN
ZnO
LiNbO3
Current response: e31,f (C m-2)
-14.7
-1.0
-0.7
-5.8
Voltage response: e31,f /eoe33 (GV
-1.2
-10.3
-7.2
N/A
0.2
0.11
0.06
0.02
~300
~1100
N/A
1210
7.2
4
5
11
m-1)
Coupling Coefficient (kp,f)2 on Si
Curie Temperature Tc (C)
CTE a (10-6 K-1)
AlN appears to be the most promising of all, due to its high insulation, and good mechanical compatibility
with the host structure (Ti-Al-N, Ti, and Cr).
CTE: H13  11x10-6 K-1; Ti  8.6x10-6K-1; Cr  4.5x10-6K-1; Pt  8. 8x10-6K-1;
(LiNbO3 also has potential with CTE match with H13)
Deposition details
Electrode deposition (Ti, Pt/Ti) (DC magnetron)
Base
Pressure
Operating
Pressure
Sputter
gas
Power
Time
1 X 10-6 Torr
3-30 mTorr
Argon
200-500 W 5-10 min.
Deposition of the piezo-layer (AlN) (Pulsed DC magnetron)
Base
Pressure
Operating
Pressure
Sputter
gas
Frequency
Power
Time
1 X 10-6 Torr
10-50 mTorr
Argon &
Nitrogen
100 kHz
200-300 W 30 min.1 hr.
Methods to test the prototype sensor architecture:
Load (Quasi-static)
Piezo-cantilever: cross section
substrate
(12)
In-plane
tensile stress
(12)
Piezo-layer
Induced charge
Apply
pressure
Electrode
Aluminum nitride
Electrode
Substrate
Damping element
electrodes
integrator
clamp
Output charge
 e31.12
Release
pressure
Static testing: Direct method
t (Sec.)
Dynamic testing: Indirect method
(Plank method)
Ease of Release Test
Surface Treatment
Coating
Name
Quantity
None
None
None
None
None
None
None
(Cr/Al)2O3
CrC-TiAlN
TiN-TiAlN
CrN (Not Graded)
MoZrN
CrN (Graded)
None
ACSEL (Multi-Layer)
Balzer
Hard Chrome
Ion Bond
Teer
Phygen
None
3
3
3
3
3
3
3
(Cr/Al)2O4
CrC-TiAlN
TiN-TiAlN
CrN (Not Graded)
MoZrN
CrN (Graded)
None
ACSEL (Multi-Layer)
Balzer
Hard Chrome
Ion Bond
Teer
Phygen
None
3
3
3
3
3
3
3
(Cr/Al)2O4
CrC-TiAlN
TiN-TiAlN
CrN (Not Graded)
MoZrN
CrN (Graded)
None
ACSEL (Multi-Layer)
Balzer
Hard Chrome
Ion Bond
Teer
Phygen
None
3
3
3
3
3
3
3
Ion
Ion
Ion
Ion
Ion
Ion
Ion
Nitride
Nitride
Nitride
Nitride
Nitride
Nitride
Nitride
FeNC
FeNC
FeNC
FeNC
FeNC
FeNC
FeNC