Gradient CrCN cathodic arc PVD coatings

This work reports on the growth and properties of Cathodic Arc Physical Vapor Deposition of low friction-coefficient CrCN coatings, as deposited on the basis of complementary carbon/nitrogen gradient concentrations through the film thickness. The coatings developed in this study exhibited friction coefficients ranging from 0.2 to 0.6, against 100Cr6 bearing steel, depending on the preparation conditions. Gradient CrCN films with COF of 0.35 and comparable mechanical strength to that of CrN were achieved. The adhesion rate of metallic elements such as Fe during the sliding process of CrCN coated tools on AISI316L steels were monitored using a pin-on-disc experimental set-up. The results demonstrated a low tendency of the gradient CrCN deposited films to pick up material from the AISI316L steels surfaces, in contrast to that found when using standard CrN cathodic arc PVD films.