Properties of P/M 316L stainless steel sintered in dry hydrogen atmosphere

The sintering process represents always a critical step in the production of stainless steel sintered parts, limits to increasing the properties of sintered parts are related to some processing parameters and plants. With the aim to deepen the knowledge about the influence of the sintering parameters and to verify the possibility to further improve the characteristics of 316L sintered stainless steel parts, the influence of sintering atmosphere constituted by dry hydrogen has been studied, taking into account for the effects of compacting pressure and of sintering time and temperature. Tests have shown the effect of the compacting pressure and of the increase of sintering time and temperature in producing smaller pores and less interconnection. Two diffusion mechanisms for removing carbon during sintering were highlighted and the influence of processing parameters and of carbon contents on the corrosion resistance of the samples was tested in 0.5 M sulfuric acid.