Some new Ni-based composite coatings with different amount of TiCN particles were prepared on the surface of Ti-6Al-4V (TC4) substrate by laser cladding. The microstructure and phases were obtained by scanning electron microscopy, energy-dispersive spectrometer and x-ray diffractometer. The microhardness and wear resistance were also tested by Vickers hardness tester and friction and wear tester. The results showed that all coatings had a good metallurgical bonding with TC4 substrate. Some new phases appeared in coating, such as Ti, Ti2Ni, TiCN, TiC, TiN, Cr2Ti and TiAl3. The microstructure was mainly composed of block crystals and dendrites. When the amount of TiCN was 15% and 20%, spherical crystals appeared in coating. The values of average microhardness were 885.1, 890.6, 923.2, 973.7 and 943.1 HV0.2, respectively. And the wear volumes were 0.39, 0.13, 0.12, 0.09 and 0.44 mm3, respectively. When the amount of TiCN was 15%, the coating had the maximum average microhardness due to the appearance of TiC, TiN and Ti2Ni phases. It also had the best wear resistance. It can be seen that the average microhardness and wear resistance were improved obviously due to the addition of TiCN particles.
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