EFFECTS OF HEATING RATE AND SINTERING TEMPERATURE ON MICRO FORMING OF 316L STAINLESS STEEL POWDER UNDER MULTIFIELD COUPLING

Abstract

316L stainless steel powders with an average particle size of 20 μm were sintered at different heating rates under multi-field action in a Gleeble-1500D thermal simulation instrument. It was shown that both heating rate and sintering temperature directly affected the densification of sintering products, and the electric field not only provided the Joule heat for densification of pre-form, but also accelerated the diffusion of atoms, which leads to intensified sintering. Multi-field action includes the stress field, temperature field and electric field, and these fields work reciprocally rather than independently. The relative density of the sintered compact can be of the order of 88.9% at relatively low temperature (500 ⁰C) within relatively short sintering time (6 min).