Effect of the Degree of Aluminum Doping on the Mechanical and Tribological Characteristics of Titanium-Aluminum Nitride Films

Abstract

The mechanical and tribological characteristics of titanium–aluminum nitride films deposited by the reactive magnetron sputtering of Ti–Al mosaic targets with different aluminum concentrations were studied. The dependences of the elemental composition, microhardness, and friction coefficient on the degree of doping of the films with aluminum and nitrogen concentration in the Ar/N2 gas mixture during film deposition were obtained. It was found that an increase in the aluminum content in the film results in an increase in film hardness and decrease in the friction coefficient. The optimum nitrogen concentration in the film was achieved at maximum hardness and low values of the friction coefficient. A maximum hardness of 23.5 GPa and a minimum friction coefficient of 0.082 were obtained for films of the composition Ti5AlN1.33, which had a Ti/Al ratio of 5 : 1 and a nitrogen deficiency.