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In the present research, the TiN/Ti multilayer coatings with different layers were fabricated on Ti6Al4V substrates with same deposition time by high-power DC reactive magnetron sputtering. Their microstructure, phase constituent, mechanical properties and wear behavior were studied to explore the influence of the layer number. The results reveal that increasing of layer number in TiN/Ti multilayer coatings refines the grains and promotes the transformation of the crystal orientation preference of the TiN layer from (111)TiN to a mixture of (111)TiN, (200)TiN and (220)TiN. Moreover, the thickness of the TiN/Ti multilayer coating increases with the increased layer number. The Ti interlayer and TiN layer have a sinuous interface at the atomic scale with many dislocations, and no orientation relationship between these layers is found. With the increasing of layer number, the elastic modulus and hardness of the TiN/Ti multilayer coatings increase firstly and then decrease. The two-layer and four-layer TiN/Ti multilayer coatings obtain the maximum elastic modulus and hardness, respectively. Moreover, the increased layer number improves the adhesion of the TiN/Ti multilayer coating obviously, and the twelve-layer TiN/Ti multilayer coating obtains the highest adhesion, which could be ascribed to the relaxation of interfacial stress. The increased Ti interlayers promote the diversification of the friction coefficient of the TiN/Ti multilayer coatings. With the proceeding of wear test, the friction coefficients of the one-layer and two-layer TiN/Ti multilayer coatings maintain an increasing tendency, but the friction coefficients of the four-layer, eight-layer and twelve-layer TiN/Ti multilayer coatings drop at final, middle and initial stage, respectively. The one-layer, two-layer and four-layer TiN/Ti multilayer coatings have similar wear rates which are less than one twentieth of the wear rate of the Ti6Al4V substrate. While the wear rates of the eight-layer and twelve-layer TiN/Ti multilayer coatings are higher than that of the Ti6Al4V substrate.

TiN/TiAlN multilayer coatings were deposited on M2 high speed steel by a pulsed bias arc ion plating system. The effect of modulation ratio on the microstructure, mechanical and wear properties was investigated. TiN/TiAlN multilayer coatings were crystallized with orientations at the (111), (200) (222) and (311) crystallographic planes and the microstructure was strengthened at (111) preferred orientation. The average atom ratio of N was about 0.39. With the increase of TiN modulation ratio from 50s:100s to 100s:50s, the atom ratio of Ti increased from 0.42 to 0.518 and the atom ratio of Al decreased from 0.193 to 0.084. At modulation ratio of 60s:90s, the hardness of TiN/TiAlN multilayer coatings reached the maximum of 40.7 GPa, which was 4.5 times that of the substrate. The adhesion strength reached the maximum of 74 N at modulation ratio of 100s:50s. Friction and wear analysis was carried out by pin-on-disc tester at room temperature. Compared with the substrate, all the specimens coated with TiN/TiAlN multilayer coatings exhibited better tribological properties.

DLC films with dispersed high crystallinity CrN nanoparticles were prepared by high power pulsed magnetron discharge plasma ion implantation deposition(HPPMS-PIID) combined with DC magnetron sputtering(DCMS).The surface morphology,structure and properties of CrN-DLC films with the different currents of C target were studied.The results show that the C content increases as the raise of the current of the C target and clear characteristics of DLC films are found at a higher C content.CrN doped in DLC exists as nanoparticles with highly 200 preferred orientation, and the smallest size of the CrN grains is 42.39 nm.The C1s peak primarily consists of the three peaks that correspond to C-sp~2,C-sp~3 and CN-sp~3,and the ratio of total sp~3 to sp~2 is 44.8%.Excellent adhesion between film and substrate with critical load of 66.8 N and high nanohardness up to 24.3 GPa are achieved due to highly energetic ion bombardment and implantation in HPPMS-PIID.