Friction and wear behavior of duplex-treated AISI 316L steels by rapid plasma nitriding and (CrWAlTiSi)N ceramic coating

Abstract Due to their high corrosion resistance, non-transformation, and non-magnetism, austenitic stainless steels can meet the service requirements. However, their low hardness and poor wear resistance impose serious drawbacks. A combination of plasma nitriding and coating as a surface treatment has been shown to improve the wear resistance without affecting the corrosion performance. In this work, the rapid plasma nitriding has been conducted on AISI 316L austenitic stainless steels using a hollow cathode discharge assisted plasma nitriding apparatus. The CrN/CrTiAlSiN/WCrTiAlN multilayers coating consisted of a CrN bottom-layer, a CrTiAlSiN interlayer, and a WCrTiAlN top-multilayer was successfully prepared using cathodic multi-arc evaporation. This ceramic coating was deposited on the surfaces of untreated and nitrided AISI 316L steels. Characterizations of the polished, rapid plasma-nitrided (RPN), only-coating, and duplex (RPN and Coating) samples were compared. Furthermore, the mechanical properties of the samples were evaluated by nano-indentation and Vickers micro-hardness tests. The dry sliding-wear characteristics were investigated by ball-on-disk wear tests against bearing steel counterparts. Tribology measurements revealed that an optimized multilayered coating followed by pre-nitriding results in excellent anti-friction and highly wear-resistant surfaces.