Injection Molding of Stainless Steel Powders

Abstract

The injection characteristics and the sintering behaviors of binary mixture of stainless steel powders having diffrent particle sizes were investigated. Two types of SUS316L powder, the higher-pressure water atomized powder (SF, d=9.72μm)and the gas atomized powder(GA, d-25μm)were used. The results obtained were as follows.
1)With decreasing the SF/GA ratio, the amount of required binder for injection molding could be diminished and the apparent density of molded compacts increased.
2)Sinterability of the molded compacts markedly increased with increasing the SF/GA ratio, while the increase of the ratio tended to result excessive grain growth when sintered at temperature above 1250°C. 3)Injection molded compacts showed uniformly distributed fine spheroidized pore structures as compared to those of die pressed compacts, after sintering.