Microstructure, mechanical and electrochemical properties of Ti₃AlC₂ coatings prepared by filtered cathode vacuum arc technology

Ti₃AlC₂ MAX phases have attracted increasing attention due to their unique properties. However, high synthesis temperatures of Ti₃AlC₂ bulk materials limit their further development. In this work, Ti₃AlC₂ coatings were prepared by a two-step method with filtered cathode vacuum arc (FCVA) deposition at room temperature and annealing at 800 °C for 1 h. The structure and properties of coatings were investigated. The results showed that the formation of Ti₃AlC₂ phase in the annealed coating depended on the C₂H₂ flow rate during deposition. At low C₂H₂ flow rates (≤ 9 sccm), almost no Ti₃AlC₂ phase was formed. As the C₂H₂ flow rate increased, the annealed coatings mainly exhibited Ti₃AlC₂ phases, the texture of which transformed from (104) to (105) planes. Meantime, the hardness of Ti₃AlC₂ coatings continuously increased to a maximum of 20.7 GPa, and the corrosion resistance first increased and then decreased with the increase of C₂H₂ flow rate.