DESULFURIZATION OF 316L STAINLESS-STEEL CONTAINING MNS DURING SINTERING

The desulfurization of MnS-added 316L stainless steel compacts which w ere sintered in hydrogen, argon, vacuum, and dissociated ammonia was i nvestigated. Pure hydrogen reduced the sulfur content by 91% when comp acts were sintered at 1200 degrees C for 1hr. This level of sulfur red uction is much higher than reported previously for low alloy iron comp acts. The main cause for this difference in sulfur reduction is that n ickel in stainless steel has a catalytic effect through the formation of H2S. This desulfurization effect must be considered in selecting th e sintering atmosphere for stainless steel compacts to which MnS has b een added in order to retain the advantage of enhanced machinability.