Comparison of tribological behaviors of PVD Cr- Ti- N coatings produced by cathodic arc evaporation technique

In the current study, (Ti, Cr)N coatings were deposited on the D6 tool steel substrates. Physical and mechanical properties of coatings such as microstructure, thickness, phase composition and hardness were evaluated. The friction and wear behavior of the coatings were investigated using ball-on-disc test under normal loads of 5, 7 and 9 N at sliding distance of 500 m, at room temperature. Phase compositions were studies by X-ray diffraction method. Mechanical properties were determined by nano-indentation technique. Scanning electron microscope and energy dispersive spectroscopy were utilized to investigate the microstructures and wear mechanisms. The results clarified that the wear resistance of (Ti, Cr)N and TiN coatings were better than CrN coating. Wear resistance of the Cr-Ti-N coatings was related to Ti content and increased with increasing Ti content. The dominant wear mechanisms were characterized to be abrasive and tribochemical.