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1. P/M (Powder Metallurgy) Joseph Tunick Strauss
HJE Company, Inc.
Glens Falls, South Glens Falls, and Queensbury, NY
2. Powder Metallurgy (P/M)
7. I Introduction (cont.) POWDER METALLURGY (P/M):
Full-scale Industrialization in past 50 years
>$1.8 Billion per year in North America
P/M Processing has Shown Continuous Annual Growth for the Past 50 Years by
1) Replacing Existing Technologies
2) "DFM: Designed for Manufacturability"
Keep in mind that powder cost more than equivalent
cast or wrought material
8. II General Summary of The Science of P/M P/M consists of three fundamental steps:
a) Powder Production
b) Powder Consolidation
c) Sintering
9. II General Summary of The Science of P/M a) Powder Production
Atomization
Electrolytic, precipitation
Mechanical
Chemical, reduction
10. II General Summary of The Science of P/M a) Powder production by Atomization:
Disintegration of liquid stream by a second fluid
Gas Atomization
Spherical powder particles
Good "flowability"
Water Atomization:
Irregular powder particles
Good compactability
16. II General Summary of The Science of P/M c) Sintering:
Heat treatment to promote metallurgical integrity
Metallurgical Bonding
Densification (shrinkage)
Pore Elimination
19. III P/M Manufacturing Techniques Net Shape Processing Die Compaction
Use water atomized powder (irregular shape)
Rigid tooling: tool steel, WC/Co
Pressures up to 60 tons/square inch
Production > 10,000 parts
High tolerance, 0.001 "/" possible
High productivity
Controlled porosity, density (85% to 90%)
22. III P/M Manufacturing Techniques Net Shape Processing MIM (Metal Injection Molding)
Plastic Injection Molding + Powder Metallurgy (P/M)
Complex Shapes
High density metal parts (> 95%)
Economy of Scale (high productivity)
Good tolerance, .003 "/" possible, .005-.008 "/" typ.
Competes with investment casting
and discrete machining
27. P/M Press-Sinter-Forge
vs. Power Forge
Better material utilization
Fewer tool sets
Reduction of secondary machining operations
Large end bearing bore and mating flats
Eliminate balancing
29. IV Applications, General Case Studies: Orthodontia Brackets MIM vs. Discrete machining and Investment casting:
Elimination of all machining operations
Better material utilization (no chips, sprues, etc)
Able to produce smaller parts than investment cast
Able to produce more complex geometries than machining
Massive reduction in labor
Complete payback in about 2 years