Effect of Cu content on the wear resistant behavior of arc-sprayed laminated-structured Cu–TiN/TiO2 composite coating

Abstract

The wear and corrosion effects in marine or coastal environments are critical issues that seriously deteriorate the service performance of marine infrastructure. Thus, development of an effective and long-lasting wear-resistant and corrosion-resistant protective coating is highly desirable. By controlling the diameter ratio of different heterogeneous metal wires during the supersonic arc spraying process, a laminated-structured Cu-TiN/TiO2 metal-ceramic composite coating with a Cu content of 8.3 % -66.6 % was fabricated. The effects of Cu loading on the microstructure, morphology, mechanical properties, and wear resistance of composite coating were analyzed. The results of scanning electron microscopy and nanoindentation tests indicated that the composite coating exhibited a dense microstructure, with tight interlayer bonding, and a gradient change in hardness and Young's modulus with Cu loading. The friction and wear tests under different loads and wear environments shown that the composite coating had excellent wear resistance. The composite coating with 8.3 % Cu loading had stronger resistance to plastic deformation and abrasive wear under dry sliding friction with 5 N and 10 N loads. The composite coating with 35.8 % Cu loading shown the most significant lubrication and friction reduction effect of Cu under dry sliding friction at a larger load of 20 N, showing the best wear resistance. The wear test under 10 N load with 3.5 wt% NaCl corrosion solution shown that the composite coating with 8.3 % Cu load had a more prominent role in resisting corrosion wear. These results may guide the preparation of high hardness, wear and corrosion resistant Cu-TiN/TiO2 metal-ceramic composite coating with appropriate Cu loading capacity through simple and effective preparation methods and easily customized raw materials, according to different wear and corrosion conditions.