COMPACTING AND SINTERING OF METAL POWDERS WITHOUT THE APPLICATION OF PRESSURE

Technical Report · Sat May 25 04:00:00 EDT 1957

OSTI ID:4306427

Hausner, H H; Ferriss, D P; Heck, F W

The properties of a mass ef loose powders are compared with those of powders compacted under pressure, and it has been shown that uncompacted powders have many properties which facilitate sintering. The rate of sintering, expressed in terms of denification, has been determined for uncompacted 316 stainless steel powders for the sintering temperature 1300 deg C. Various mixtures of fine and coarse powder particles were prepared in order to determine the mixtures which result in maximum apparent density (approximately 60% coarse - 40% fine particles). It has been shown that maximum apparent density is not necessary, nor even desirable, to parent density is not necessary, nor even desirable, to obtain maximum sintered density, which can be reached with mixtures of approximately 20% coarse -80% fine particles. The experimental work revealed that the sintered density is a function of the density of the powder mass before sintering plus another functionthat of the total particle surface area. It has been shown further that, without any application of pressure to the powder, sintered densities is high as 7.0 g/cc, or 87.8% of the material's theoretical density, can be obtained at a relatively low sintering temnperature. (auth)

• Research Organization: Penn-Texas Corp., New York; Stevens Inst. of Tech., Hoboken, N.J. Powder Metallurgy Lab.
• NSA Number: NSA-12-010620
• OSTI ID: 4306427
• Report Number(s): NYO-8526
• Country of Publication: United States
• Language: English

Related Subjects

COMPACTING
DENSITY
GRAIN SIZE
HIGH TEMPERATURE
MINERALOGY, METALLURGY, AND CERAMICS
PARTICLES
POWDERS
PREPARATION
PRESSURE
SINTERING
STAINLESS STEELS
VARIATIONS