Abstract:In order to solve the problem of poor thermal conductivity of traditional tool coatings with high wear resistance, the (TiAlTaCrZr)N coatings were prepared by DC magnetron sputtering under different nitrogen flow rates. The effects of different nitrogen contents on the microstructure, hardness, adhesion and thermal conductivity of the coatings were studied. With the increase of nitrogen flow rates, the content of N in the coatings increases, and the microstructure of the coatings changes from nanocrystalline to columnar crystal. The hardness of the coatings increases from 11.0 GPa of the TiAlTaCrZr coating to 20.6 GPa of the (TiAlTaCrZr)N coating with 5 SCCM nitrogen flow rate. The adhesion of the coating reaches to the value of 130 N when nitrogen flow is 5 SCCM, and then decreases gradually with the increase of nitrogen contents. The thermal conductivity of the (TiAlTaCrZr)N coating is better than that of the TiAlN coating, but the thermal conductivity decreases with the increase of nitrogen contents. Since the (TiAlTaCrZr)N coating have high thermal conductivity, high adhesion and high hardness, the cutting length of the (TiAlTaCrZr)N coating is 175% higher than that of the TiAlN coating for titanium alloy cutting. It provides a new tool coating with high wear resistance and high thermal conductivity for titanium alloy cutting.