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With the rapid development of modern industry in China, the operating requirement of hot working dies increasingly high. Due to poor working conditions and the severe changes of hot and cold, the failure of H13steel is often found under thermic fatigue, thermic wear or cracking. Therefore, improving its performance and service life by way of surface modification technology is of great significance.In this present work, CrTiAIN thin films deposited on the H13steel by closed-filed unbalanced magnetron sputtering ion plating coater. The microstructure, morphology and composition were characterized and analyzed by using XRD, OM, SEM, EDS; the hardness and adhesion was measured by vicker microhardness meter and scratch test; the tribological properties was evaluated by friction and wear spectrometer. Effect of different target-substrate distance, different hardness of matrix and different thermal oxidation temperature on microstructure, composition and performance of CrTiAIN films were analysised.The results show that CrTiAIN thin films have homogeneous microstructure, fine grain size (about200mn), and with a polycrystal fcc structure exhibited a (111) preferred orientation. Its crystal structure is similar with CrN, but the lattice constant is slightly expanded. With the target-substrate distance increases, the content of metallic element continues to decline while the N element continues to rise; the surface hardness and adhesive force of film increase and then decrease while the friction and wear rate increase gradually with the target-substrate distance increases, the film has the best performance when the target-substrate distance of120mm; the performance of the higher matrix hardness film is better than the lower matrix hardness; the performance of film decrease gradually with increasing the oxidation temperature, thermal stability of film can be maintained to800℃, comprehensive performance of thin film decline seriously above this temperature, and the film is no longer applicable.
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