1 near full density as sintered powdered metal (p/m) parts produced from water atomized powder with...
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1
Near Full Density As Sintered Powdered Metal (P/M) Parts
Produced From Water Atomized Powder With Properties
Comparable To Wrought Steel
Richard R. Phillips - Engineered Pressed Materials
Dennis Hammond - APEX Advanced Technologies, LLC
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Key Features of the Technology
• Water atomized powder
• Low alloy steel -100 mesh
• >99.5% theoretical density
• Properties comparable or superior to
wrought steel
• Standard tooling/ conventional pressing
• Normal compaction range
3
Key Features of the Technology Continued
• High temperature sintering < 2500F (atmospheric or vacuum)
• Conventional steel heat treating
• Post heat treating operations similar to wrought processing
4
Lubricant Requirements For Near Full Density P/M Parts
• Increase green density
• Mobility of the lubricant
• Effective removal of the lubricant
• Excellent dimensional stability
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High Green Density with Standard Equipment
• Reduced level of lubricant, typical use level .25%-.4%
• Green Densities 7.2-7.4 g/cc typical for common formulas
• Micro cracking and delamination eliminated• Green density increased due to reduced volume of
lubricant and better fit of particles resulting from mobility of the lubricant
• Lubricant is more effective
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Mobility of Lubricant
• Lubricant transforms with shear, pressure, and friction from a solid to a viscous liquid at relatively low pressure (~ 4 tsi with shear)
• Mobility allows for effective rearrangement of metal particles
• Mobility allows for lubricant to be forced to the die wall as well as hydrostatic environment within the compact
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Effective Removal of the Lubricant
• Environmentally friendly,contains no metal• Staggered decomposition rate• Up to 70% less gas trying to exit the part at
peak decomposition relative to conventional lubricants
• Elimination of cracking and blistering with high nickel formulas
• Elimination of recondensation of lubricant on part surfaces
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Excellent Dimensional Stability
• No micro cracks or delamination
• Small uniform pore size in the green state
• No unplanned density gradients in the part
• Relatively stress free green part
• Density split eliminated
• Uniform, predictable shrinkage
• Enhanced sintering efficiency
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Other Part Attributes
• Good surface finish
• Good ejection with reduced level of lubricant
• Due to the high green densities achieved, excellent green strength is also obtained
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Density Gradient – Shape Retention
TOP
BOTTOM
B
A
C
A B C
One direction Dual Elimination of compaction direction Die Wall compaction Friction and Density Split Dg = 7.0 g/cm³ Df = 7.82 g/cm³ 7.82 7.0 ≈ 3.8 ΔL; ≈ 0.038”/in.
≈ 11.7% Increase in D
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6.20
6.60
7.00
7.40
7.80
DE
NS
ITY
(g/
cc)
Mpa 276 414 552 690 828
Green 6.38 6.79 7.04 7.19 7.29
Sintered 7.81 7.82 7.82 7.81 7.81
20 30 40 50 60
Pressure/Density Curve FLN-0706
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Materials and Processing(Experiments)
Standard MPIF ASTM Comments
Density 42 B328 Modified Method
Hardness Macro 43 E18
Impact Notched E23
Impact Un-notched 40 E23
Modulus of Elasticity 10 E8
Ultimate Tensile Strength
10 E8
Yield Strength 10 E8
Elongation 10 E8
Microstructure E3
Photomicrographs E883
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Test Alloys
•Hoeganaes Ancorsteel 85HP and 150HP formulated to provide a resulting alloy with 0.56%Carbon and Nickel contents between 2 and 6.6%.
•Pressed at 276 (20),414 (30), 552 (40) ,690 (50), and
828 (60) MPa (TSI).
•Vacuum or Atmosphere High Temperature Sintering
•Heat Treated to Commercial Wrought Steel Properties
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Tensile DataSample
TypeDensity,
g/ccUTS, MPa (103 psi)
0.2% YS, MPa (103 psi) % Elong. % ROA
Mod of Elas., GPa (106 psi)
Hardness HRC
Pressed 7.81 1,486 (215) 1,296 (187) 3.1 188 (27.3) 43.5
Machined 7.79 1,383 (200) 1,304 (189) 2.9 9.34 182 (26.4) 45.0
Pressed 7.59 1,446 (209) 1,205 (175) 4.0 158 (22.9) 39.7
Machined 7.57 1,414 (205) 1,248 (181) 4.2 10.48 162 (23.5) 38.7
Pressed 7.82 1,182 (171) 955 (138) 5.2 183 (26.6) 34.3
Machined 7.79 987 (143) 939 (136) 3.5 11.51 192 (27.8) 35.4
Pressed 7.46 1,051 (152) 685 (99) 4.4 141 (20.4) 28.0
Machined 7.57 1,314 (190) 1,211 (176) 4.9 15.92 164 (23.8) 37.5
Pressed 7.76 1,062 (154) 803 (116) 8.6 170 (24.6) 32.0
Machined 7.79 1,036 (150) 787 (114) 4.2 13.48 171 (24.8) 32.6
Pressed 7.60 1,188 (172) 690 (100) 4.0 136 (19.8) 36.7
Machined 7.57 1,089 (158) 730 (106) 7.4 15.19 135 (19.6) 32.0
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Comparison to Wrought Tensile Data
GradeUTS
MPa (103 psi)0.2% Y.S.
MPa (103 psi) % ElongationHardness, HRC Scale
ANP FLN-0706Range of Data
1,486 (215.4)1,383 (200.5)
1,296 (187.9)1,304 (189.1)
3.1/2.9 43.5/45.0
AISI 4140 1,449 (210) 1,346 (195) 14 45
AISI 4340 1,449 (210) 1,325 (192) 14 45
AISI 5140 1,304 (189) 1,228 (178) 14 40
AISI 4150 1,573 (228) 1,484 (215) 9 47
AISI 5150 1,435 (208) 1,346 (195) 11 45
AISI 6150 1,401 (203) 1,325 (192) 10 46
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Comparison to Wrought Tensile Data
GradeUTS
MPa (103 psi)0.2% Y.S.
MPa (103 psi) % ElongationHardness, HRC Scale
ANP FLN-0706Range of Data
1,182 (171.3)987 (143.1)
955 (138.4)939 (136.1)
5.2/3.5 34.3/35.4
AISI 4140 1,021 (148) 917 (133) 18 33
AISI 4340 1,049 (152) 979.8 (142) 18 34
AISI 5140 911 (132) 800 (116) 20 28
AISI 4150 1,242 (180) 1,118 (162) 12 39
AISI 5150 980 (142) 911 (132) 18 31
AISI 6150 1,125 (163) 1,063 (154) 15 36
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Comparison to Wrought Tensile Data
GradeUTS
MPa (103 psi)0.2% Y.S.
MPa (103 psi) % ElongationHardness, HRC Scale
ANP FLN-0706Range of Data
1,062 (154.0)1,036 (150.2)
803 (116.5)787 (114.2)
8.6/4.2 32.0/32.6
AISI 4140 814 (118) 697 (101) 23 22
AISI 4340 911 (132) 800 (116) 24 20
AISI 5140 787 (114) 580 (84) 27 95 HRB
AISI 4150 876 (127) 807 (117) 20 27
AISI 5150 807 (117) 711 (103) 23 23
AISI 6150 814 (118) 738 (107) 22 23
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Charpy Impact Comparison
Density, g/cc
FLN-0706
(No Notch), ft-lbf
FLN-0706
(Notched), ft-lbf
Wrought
(Notched), ft-lbf
7.8 50 7 12 - 17
7.6 55 6
7.8 77 13 36 - 56
7.6 67 11
7.8 84 77 - 87
7.6 70
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Size Change/Coefficient of Variance
Coefficient of Dimensional Variance (%)
Equal to the standard deviation divided by the average multiplied by 100
Pressed Direction 0.17%Perpendicular to Pressed Direction 0.084%
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Cylinders
Back row in the as-molded condition.Front row in sintered and heated condition.
OD = 1.880” , OAL = 1.755”, 1.500”, 0.750”, 0.500”
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Processed Samples
Samples in molded, sintered and heat treated, and machined condition. (7.81 g/cc, 45 HRC)
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Gears, Pawls and Rollers
Back row in the as-molded condition.Front row in sintered and heated condition.
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Density
6.70 g/cc(85% Theoretical Density)
7.41 g/cc(95% Theoretical Density)
7.84 g/cc(>99.5% Theoretical Density)
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P/M and Other Process Costs
75%
100%
125%
150%
175%
200%
225%
7.0 7.1 7.2 7.3 7.4 7.5 7.6 7.7 7.8 7.9
Density (g/cm3)
Rel
ativ
e C
ost
Single Press &Sinter Warm Compaction
Double Press&
Double Sinter
High Velocity Compaction
High Velocity Compaction (Double Press – Double Sinter)
Powder Forge
ActivatedTM NanotechTM
Sinter
Machining & Precision Casting
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Conclusions• ANPTM* processing of -100 mesh ferrous powder
alloys creates material properties similar to wrought product.
• ANPTM utilizes conventional blending, tooling and P/M molding capabilities.
• Lubricant choice plays a critical role.• ANPTM is activated during high temperature sintering
resulting in densification > 99.5% of theoretical (pore-free).
• ANPTM dimensional control is predictable and uniform within < 0.2% variance.
ANPTM, ACTIVATEDTM NANOTECHTM are trademarks of Material Technologies, Inc.*Patent Pending
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Conclusions (cont.)• ANPTM can utilize conventional wrought metal
processing to meet specific engineering design requirements to enhance optimum product performance.– Machining without lubricant intrusion.– Plating without impregnation.– Salt Bath Processing
• Kolene Nu-tride• Blueing
– Ferritic Nitrocarburizing (Atmosphere).
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