Surface coating has been widely used to ameliorate the surface properties of Ti alloys. In this study, high-power pulsed magnetically controlled sputtering technology was used to successfully prepare a nano-CrN/TiN multi-layered coating on the surface of a TC4 Ti alloy. The surface of the obtained coating was uniform, dense, and free of obvious defects. With the decrease in modulation period, the optimal growth of the nano-CrN/TiN multi-layered coating was changed from a (220) crystal surface to (111) and a (200) crystal surface. Compared to the single-layered CrN or TiN coating, the nano-multi-layered coating had higher hardness and lower wear rate. Furthermore, the hardness and the wear resistance increased with the decrease in the modulation period. This presented an optimal modulation period of 6 nm. Meanwhile, the resistance of the obtained coating to high-temperature oxidation at 800 °C was also significantly improved.
Keywords: high-temperature oxidation; nano-multi-layered structure; surface coating; wear.