Effect of Refractory Element Additions on the Properties of Sintered Stainless Steels

Abstract

This paper studies the change in properties of powder metallurgical 316L stainless steel when pure vanadium, molybdenum and tungsten (3% vol.) are added. The objective is to study the possibility of nitrogen pick-up by these refractory elements better than the chromium from plain steel. All materials have been manufactured mixing the powders with a 0.6% (wt.) of wax. Compaction was carried out at 700 MPa, and green density was evaluated. Finally, sintering was done (for 30 min) in 25%N 2 -75%H 2 at 1230 °C. Evaluated properties include sintering density, hardness, and corrosion (through salt spray test), and a broad microstructural study (optical and scanning electron microscopy) was also carried out.