Composition Design And Performance Study Of HfMoNbZr-based Nitride Coatin

The current cutting tool industry is facing challenges such as high wear and short service life.High entropy nitride as a new multi-material coating,the four core effects make the coating has the high strength,excellent wear resistance and high temperature stability and other advantages,in the industrial field of application of great prospects.In this paper,HfMoNbZr N_x,Al_xHfMoNbZr N and Ti_xHfMoNbZr N coatings were prepared by controlling the deposition parameters of magnetron sputtering,and the mechanism of the effect of N,Al and Ti content on the structure and properties of the coatings was systematically described using different microscopic characterisation techniques and performance testing methods.In this paper,HfMoNbZr N_x,Al_xHfMoNbZr N and Ti_xHfMoNbZr N coatings were prepared by controlling the deposition parameters of magnetron sputtering,and the mechanism of the effect of N,Al and Ti content on the structure and properties of the coatings was systematically described using different microscopic characterisation techniques and performance testing methods.HfMoNbZr N_x was also prepared using radio frequency magnetron sputtering（RFMS）and direct current magnetron sputtering（DCMS）techniques to investigate the mechanism of the effect of N in the multi alloy coatings under different deposition methods.The following results were obtained.For the HfMoNbZr coating structure prepared by RFMS is amorphous and the nitride coating structure is NaCl-type FCC structure;the hardness of the nitride coating is highest at 21.8±0.88 GPa when the nitrogen-argon flow ratio（R_N）is 10%;the N doping has a positive effect on improving the resistance of the multi alloy coating to wear loss.The structure of the multi-alloy coating prepared by DCMS is also amorphous,and the introduction of nitrogen causes the coating to crystallise rapidly.With 15%≤R_N≤20%,the coating appears as FCC+BCT biphase structure,corresponding to the highest hardness and elastic modulus of the nitride coating,29.3±1.35 GPa and 314.3±3.29 GPa respectively.And the wear rate is as low as 6.19x10^-15 m³N^-1m^-1,which is an order of magnitude smaller for the nitride coating compared to the wear rate of the alloy coating.Al_xHfMoNbZr N and Ti_xHfMoNbZr N coatings were prepared by DCMS,respectively.The doping of Al and Ti atoms was found to have no significant effect on the phase structure of the HfMoNbZr N coatings by different tests;the solid solution strengthening effect of Al and Ti atoms resulted in increased hardness of the HfMoNbZr N coatings;the resistance of the coatings to abrasive grain wear,adhesive wear and oxidative wear was enhanced by the addition of Al elements;the HfMoNbZr N coatings were doped with Ti elements and their The wear rate decreases;in addition,the Al and Ti elements can rapidly form a dense passivation film on the surface of the coatings,which has a positive effect on the corrosion resistance of the HfMoNbZr N coating in 3.5 wt.%NaCl solution.