Structure and properties of (AlCrMoNiTi)Nx and (AlCrMoZrTi)Nx films by reactive RF sputtering

The AlCrMoNiTi and AlCrMoZrTi nitride films were prepared by reactive radio-frequency (RF) magnetron sputtering at various N2-to-Ar flow ratios (RN). The influence of RN on the structure and properties of these films was investigated. The two alloy films presented an amorphous structure, while a simple face-centered-cubic (FCC) solid-solution structure was observed in the nitride films prepared under different RN. As the RN increased, the clusters, defects and film thickness decreased, which resulted in a dense columnar structure and low surface roughness. Peak hardness of 19.6 GPa for AlCrMoZrTi nitride films and 15.4 GPa for AlCrMoNiTi nitride films were attained at RN = 1.0 respectively. At RN = 0.5, the friction coefficients of AlCrMoNiTi and AlCrMoZrTi nitride films were respectively 0.15 and 0.13. Moreover, the AlCrMoZrTi nitride films did not undergo wear-out after 1200 s friction experiment. Therefore, The AlCrMoZrTi nitride films exhibited better mechanical properties than that of AlCrMoNiTi nitride films, which may be related to the fact that the solid-solution strengthening effect of Zr was greater than that of Ni.