Effect of Al content on the properties of Cr1−xAlxC films prepared by RF reactive magnetron sputtering

Abstract Cr 1− x Al x C films were deposited on high-speed steel by RF reactive magnetron sputtering. In this study, we aimed to identify the effect of the Al content on the properties of Cr 1− x Al x C films. We found that Cr 1− x Al x C films exhibited a fine columnar grain microstructure with some special characteristics, such as high hardness of Hv 1426, a low friction coefficient of 0.29, and a large contact angle of 90° for x = 0.18. Furthermore, an increase in Al content resulted in a decrease in film hardness and an increase in contact angle. Moreover, on annealing at 923 K, the mechanical properties of the films improved and a dense protective film of complex Cr 2 O 3 and Al 2 O 3 oxides was formed on the surface for better wear resistance, which will ultimately increase the lifetime of the high-speed steel substrate.