Influence of Vacuum Gas Nitriding on Wear and Corrosion Behavior of a High Manganese Steel

Abstract

In this study, the wear and corrosion behavior of gas-nitrided high manganese steel (HMS) was investigated. Vacuum gas nitriding was carried out for surface treatment of HMS at 520 and 570 degrees C for 12, 18 and 24 h. The base metal contained alpha and epsilon martensite, while austenite was also observed in heat-treated base metal. Although all gas-nitrided samples contain Fe3N, Fe4N, gamma, alpha and epsilon martensite, FeSi phase was only determined in N1-N6 samples. Expanded martensite and white layer (complex S phase) were observed in N1-N6 and N7-12, respectively. The gas-nitriding process significantly increased the surface hardness of HMS due to the iron nitride. Daimler-Benz Rockwell-C adhesion test shows that gas-nitriding HMS has sufficient adhesion behavior. The gas-nitriding process increases the wear and corrosion resistance of the HMS significantly.