Production of TiNi/Ti2AlN Multilayer Films with Different Numbers of Layers and Evolution of Tribological and Adhesion Properties

TiNi/Ti₂AlN multilayer films are deposited on AISI M2 steel and Inconel 718 substrates using the magnetron sputtering technique. After heat treatment at 750 °C, TiNi and Ti₂AlN MAX phase crystal structures are obtained in these films. The effects of different layer numbers on the structural, mechanical, tribological, adhesion, and fatigue properties of TiNi/Ti₂AlN multilayer films are investigated. All films’ thickness is measured to be ≈2 μm. The 20 layers film deposited on Inconel 718 exhibited the best mechanical properties, with a hardness of 30.6 GPa and an elastic modulus of 407 GPa. A significant improvement in the tribological performance of the films is observed with an increasing number of layers. The lowest wear rate, calculated as 1.96 × 10⁻⁵ (mm³ (N·m)⁻¹), is observed for the 20 layers film deposited on Inconel 718 at room temperature. At high temperatures, the friction coefficients of the 16 and 20 layers films deposited on Inconel 718 decreased to 0.25. In terms of adhesion properties, the 10 layers films deposited on AISI M2 steel demonstrated the best performance with a critical load value of 45 N. The results of the multipass scratch test clearly showed that the 20 layers film deposited on Inconel 718 exhibited the best fatigue behavior among all films.