采用直流反应磁控溅射技术在M2高速钢基片上制备了不同Mo含量的CrMoN复合涂层, 研究了Mo含量的变化对CrMoN复合涂层成分、相结构、化学价态、截面形貌、显微硬度和摩擦性能等的影响．结果表明, 随着Mo含量的增加, CrMoN复合涂层的相结构先转变为以fcc-CrN相为基础的(Cr, Mo)N置换式固溶体, 后转变为以fcc-g-Mo₂N相为主的混合相, 当Mo含量为69.3% (原子分数)时, 伴有少量的bcc-Mo相生成; CrMoN复合涂层的显微硬度先增加后降低, 在Mo含量为45.4%时具有最高值; 当Mo含量大于45.4%时, 在与对磨副摩擦过程中会生成大量的MoO₃相, 降低了摩擦系数和磨损率.

Ceramic coatings are usually used as protective coatings to improve performance and durability of tools and components now. Compared with conventional TiN based hard coating, CrN based coating like Cr-X-N (X=Ti, Al, Si, C, B, Ta, Nb, Ni) is a more interesting choice because of low friction coefficient, superior oxidation resistance and excellent corrosion resistance under severe environment conditions. The CrMoN is among these coatings and attractive since self-lubricating phase MoO₃ may be formed in tribological process. However the effect of Mo content on structure and tribological properties of CrMoN coatings is not still clear. In the present study, CrMoN composite coatings with different Mo content were deposited on M2 high speed steel (HSS) substrates by DC reactive magnetron sputtering. The effect of Mo content on the microstructure and properties was investigated systematically, including the chemical composition, phase structure, chemical valence, cross-section morphologies, microhardness and tribological properties. The results showed that the phase transformation of the as-deposited coatings occurred with the increase of Mo content. The phase structure changed to (Cr, Mo)N substitutional solid solution based on CrN-type firstly, and then to mixed phase with g-Mo₂N as main phase, and a small amount of elemental bcc-Mo phase appeared when the Mo content is 69.3%. The microhardness of the CrMoN composite coatings always increased until the highest hardness when the Mo content reached to 45.4%, and then decreased; a relatively low friction coefficient was obtained compared with that of the CrN coating when more than 45.4%Mo content was doped. The reason is that the more MoO₃ lubricant phase could be formed in tribological process.