Hard CrCN/CrN multilayer coatings for tribological applications

Hard coatings were deposited using a cathodic arc evaporation method. The results of investigations of multilayer CrCN/CrN coatings are presented in this article. The microstructure and crystallinity of films have been investigated using X-ray diffraction (XRD). The composition was determined with energy dispersive spectroscopy (EDS). The adhesion of films was estimated on the basis of an analysis of scratch-test results. The hardness and tribological properties of films deposited on hardened and tempered HSS substrates were also investigated. The tribological tests were carried out in a pin-on-disc geometry. The influence of a normal load, sliding speed and a counterpart material on the friction coefficient and the specific wear rate of the coatings were studied. The counterparts were made of HSS and four types of wood: oak, beech, spruce and pine. The hardness and adhesion of multilayer CrCN/CrN coatings are respectively 25 GPa and 120 N.