Wear and friction behavior of CrTiN/TiCN and CrTiN/CrCN multilayer composite coatings

Multi-layer CrTiN/CrCN and CrTiN/TiCN coatings were deposited on 2379 and SLD steels by cathodic arc physical vapor deposition (arc-PVD) in different thicknesses. Coatings are mechanically, physically, and chemically characterized by nanoindentation, optical microscope, atomic force microscope (AFM), and scanning electron microscope/energy-dispersive X-ray (SEM/EDX) analyses. The crystal structure of the coatings was investigated by X-ray diffraction (XRD) analysis. Wear and friction characterizations were performed via reciprocating tribometer tests under 2.4 and 3.0 GPa Hertzian contact pressures at the unlubricated conditions. Results showed that CrTiN/CrCN coatings demonstrated excellent wear resistance and friction coefficient (COF) at elevated contact pressures both on 2379 and SLD steels.