High Entropy Alloys Based on Nitrides of Refractory Metals – a New Solution for Protective Coatings on the Instruments Working at High Temperatures

Abstract

The coatings based on (Ti-Al-Zr-Nb-Y)N and (Ti-Zr-Hf-V-Nb-Ta)N were obtained by means of vacuum-arc deposition from the cathodes based on Ti+Al+Zr+Nb+Yand Ti+Zr+Hf+V+Nb+Tasystems in the atmosphere of nitrogen. Their physical and mechanical properties, as well as tribotechnical characteristics have been studied. The coatings are characterized by a columnar structure and their hardness reaches 51.02GPa. The adhesion strength of the coatings has also been studied, the coefficient of friction of the system “coating – Al2O3“ is 1.1.The results of tribological tests at high temperature showed that at 460 °C coatings had greater wear resistance, lower coefficient of friction compared to similar tests of coatings at 20 °C.These coatings are perspective as protective coatings for friction pairs and cutting tools.