| (TiCr)N coatings with different Cr content and (TiCrCe)N coating were deposited on the surface of W6Mo5Cr4V2 high-speed steel(HSS) substrates by adjusting cathode arc currents of the targets of Ti, Cr and Ti-Ce alloy with arc ion plating. The effects of the content of Cr on the structure, mechanical performance (hardness, adhesion) and the property of high temperature oxidation-resistant of the coatings were studied by Scanning Electron Microscopy(SEM), Energy Dispersive Spectroscopy(EDS), X-Ray Diffraction(XRD), Micro-hardness Tester, Scratch Tester and Thermal Analyzer. The influences of rare earth element Ce on the structure and high temperature oxidation-resistant of the coating were also analyzed.(TiCr)N coatings with different Cr content were successfully deposited by adjusting cathode arc currents of the targets of Ti and Cr which can control the evaporation capacity of the targets by arc ion plating. The relationship between Cr concentration and arc current ratio of Cr/Ti conforms to quadric curve within a certain range of arc currents. (TiCr)N coating is mainly composed of TiCrN phase. CrN and Cr2N phase have been observed when the content of Cr reaches a certain quantity, resulted from which some Cr atoms in the (TiCr)N coating partly replace Ti atoms in the TiN lattice, others react with N to form CrN and Cr2N when the solid solubility of Cr is saturated. The hardness, adhesive strength and density of the coatings first increase then decrease with the increase of the Cr content, which is perhaps due to the change of phase, preferred orientation and stress of the coatings. The property of high temperature oxidation-resistant of the coatings improves with the increase of the Cr content. It is the formation of the Cr-rich oxide layer that brings about well improved oxidation-resistant of the coatings. The thermo-analysis results showed that oxidation thermodynamic temperature of (Ti1-xCrx)N (0.16≤X≤0.37) coatings were in excess of 800℃ and rose with the increase of Cr content.The introduction of rare earth element Ce in the coatings can improve the surface morphology, decrease the number and size of the droplets, which is benefit to increase the density and adhesion of the coatings. Introduction of rare earth element Ce results in the appearance of (222) and intensifies greatly (111) preferred orientation of the TiN coating. The introduction of rare earth element Ce has not changed the phase structure and intensified (220) preferred orientation of the (Ti0.7Cr0.3Ce)N coating.
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