| TiN-like films represent a class of materials with high strength and hardness, good chemical stability, wear and corrosion resistance. So these materials have wide application prospect in engineering field, such as the surface of cutting tools, dies and so on. But the current preparation technology of films exist some shortages or much or little, so a new technology which is named double-glow plasma alloying(DGPAT) is used in this study.In this paper, the processes and mechanism of forming TiC and Ti(CN) films by DGPAT had been researched. The optimization of technological condition of preparing coating had been discussed. Microstructure, adhesion, wear resistance and corrosion resistance of films had been studied. At last, the effect of alloying sequence with C,Ti,N on films had also been researched. The results show that excellent films have been prepared successfully with a special structure of source by the theory of in-situ synthesis and epitaxial growth. The thickness of two films can be up to 20μm and there are no impurities and cracks at connections. In TiC films, the only one new phase have been produced, while there are two different phase structures in Ti(CN) films which are TiC0.7N0.3 and TiC0.2N0.8 respectively. The adhesion between films and substrates is good and the best is above 70N. The surface hardness of films is high and some are over 2500HV. So in the abrade experiment, films expressed good wear-resistance which are more 7 times than substrates. Meanwhile the corrosion resistance of films is well, which is over 4 times than the substrate in both 3.5%NaCl and 5%H2SO4 solution. The last result shows the best sequence of alloying with C-Ti-N is multi-element alloying within one stage. All above results will be of great theoretical and practical reference value for TiN-like films prepared by double-glow plasma alloying.
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