Microstructure and Wear Properties of a Low Carbon Bainitic Steel on Plasma Nitriding at Different N2-H2 Gas Mixtures

For the first time, influence of gas mixture on damage resistance a plasma nitrided DIN 18MnCrSiMo6-4 bainitic steel was investigated. Samples were at 500 °C with three different N2-H2 mixtures, containing 5, 24, and 76 vol.% N2. characterized concerning resulting roughness, microstructure, compound layer’s phase composition, residual stresses in diffusion zone, surface hardness. Tribological ball-on-flat tests carried out reciprocal mode using zirconia as ball material for friction coefficient layer until damage. The test results evaluated statistically by analysis variance (ANOVA). As amount nitrogen decreases, ?-Fe2-3(C)N content decreases. A ?’-Fe4N monophasic achieved 5 N2 mixture. zone expected presented compressive highest values near surface. In tribological tests, better obtained 24 higher amounts formed. led to brittle behavior, due biphasic (?’-Fe4N ?-Fe2-3(C)N) predominant ?-Fe2-3(C)N.