Tribocorrosion Behavior of Laser Cladded Ti-Al-(C, N) Composite Coatings in Artificial Seawater

Abstract

MAX phase containing Ti-Al-(C, N) composite coatings is promising in marine engineering due to the improved tribocorrosion performance of titanium alloys. Therefore, novel Ti-Al-(C, N) composite coatings were prepared in this study using laser cladding on TC4 substrate. Electrochemical performances of as-obtained composite coatings were then analyzed under static and dynamic conditions in an artificial seawater environment, and their tribocorrosion behaviors and corrosion–wear synergism mechanism were examined by a tribocorrosion test system. The results showed that the existence of self-lubricating phases Ti2AlC and Ti2AlN in composite coatings and the corrosion products with a certain lubrication effect generated during the friction process kept the average friction coefficient at a low level. With the increase of load, the mechanical failure of the passive film in the friction process was enhanced, the adsorption of corrosive medium on the surface of the passive film led to its active dissolution, and the wear volume increased from 1.45 × 10−2 to 3.24 × 10−2 mm3. The corrosion of composite coatings in artificial seawater was not extensive, and volume loss caused by tribocorrosion was mainly determined by wear behavior. In sumary, the coatings exhibited good bearing capacity in the marine environment, thereby showing broad prospects for marine equipment applications.