The effect of substrate temperature on the properties of (AlCrNbSiTiV)N films deposited by HIPIMS

High-quality materials should always meet the requirements of industrial or consumer applications with the development of advanced technologies. In recent years, high-entropy alloys (HEAs) have been developed as new alloy materials due to their superior mechanical properties. Besides, difficult-to-cut materials have been also widely used in many different industrial applications. (AlCrNbSiTiV)N coatings as HEAs have been usually grown on tool, engine parts, MEMS processing components, and thermoelectric materials using vacuum arc and mechanical alloy methods. Hence, in order to improve the performance of tools and surface quality of workpieces in coolant-free turning process, a high-power impulse magnetron sputtering (HIPIMS) system was used to deposit (AlCrNbSiTiV)N films on the tool surface. In this study, the film thickness, deposition rate, and surface morphology at different substrate temperatures in turning chromium-molybdenum steel were investigated. The (AlCrNbSiTiV)N films coated in this study was homogeneous and very compact and showed good adhesion strength. Experimental results showed that increasing the substrate temperature from 100 to 400 °C during sputtering process indeed could improve the mobility of the atomic surface, the density of the films, and the hardness of the films. The maximum hardness and the elastic recovery rate (Re) of (AlCrNbSiTiV)N films were found to be 41.07 GPa and 80.21%, respectively, when the substrate temperature was increased to 400 °C. In addition, the performance of coated tools by (AlCrNbSiTiV)N film was comparatively much better than that of uncoated tools, which possessed broad application prospects in the future.