Influence of silicon content on the microstructure, mechanical and tribological properties of magnetron sputtered Ti-Mo-Si-N films

摘要

Ti-Mo-Si-N films with various Si content (0-17.2 at.%) were deposited by reactive magnetron sputtering and the effects of Si content on the microstructure, mechanical and tribological properties of Ti-Mo-Si-N films were investigated. The results showed that the face-centered cubic (fcc) interstitial solid solution of Ti-Mo-Si-N was formed by dissolution of Si into Ti-Mo-N lattice with the Si content in the range of 3.1-5.0 at.%. With a further increase in Si content, the films consisted of fcc-Ti-Mo-Si-N and amorphous Si_3N_4 phases. The hardness and fracture toughness of Ti-Mo-Si-N films first increased and then decreased with the increase of Si content and the highest values were 34.5 GPa and 2.6 MP m~(1/2), respectively, at 5.0 at.% Si. The average friction coefficient and wear rate of Ti-Mo-Si-N films first decreased and then increased with the increase of Si content and the lowest values were 0.35 and 7.8 × 10~(-8) mm~3/Nmm, respectively, at 5.0 at.% Si.