Austenitic Nitriding and Nitrocarburizing of steels

Austenitic nitriding and nitrocarburizing is a surface treatment for steels, usually performed at temperatures in the range of 600-725°C using the typical techniques of gas-, salt-bath- and plasma-nitriding/-nitrocarburizing. In contrast to ferritic nitriding and nitrocarburizing, an additional austenite layer is formed in between the compound layer and the diffusion zone which can be transformed into martensite or bainite, depending on the cooling rate. Solution nitriding is an alternative thermochemical treatment for corrosion-resistant steels operated with pure nitrogen to enrich the austenitic phase at the surface with nitrogen, typically at temperatures around 1100°C.