摘要
Ni–60%WC coatings were fabricated on 45 steel to enhance the corrosive–wear performance by laser cladding (LC). The effects of powder feeding speed (PFS) on the microstructure and tribological performance of obtained coatings in Wusu mine water were analyzed using a super depth of field microscope (SDFM) and ball–on–plate friction tester, and the corrosive–wear mechanism was also discussed. The results show that the surface hardness of Ni–60%WC coatings fabricated at the PFSs of 8, 10, 12, 14 and 16 g•min−1 are 2345 ± 37, 2265 ± 87, 2408 ± 55, 2405 ± 47, and 2066 ± 55 HV0.5, respectively, in which the coating hardness fabricated at the PFS of 12 g•min−1 is the highest among the five kinds of coatings. The average coefficients of friction (COFs) of Ni–60%WC coatings fabricated at the PFSs of 8, 10, 12, 14, and 16 g•min−1 are 0.270, 0.310, 0.210, 0.212, and 0.220, respectively; and the corresponding wear rates are 1.954 × 103, 2.907 × 103, 1.539 × 103, 1.923 × 103, and 3.906 × 103 μm3•s−1•N−1, respectively, where the coating fabricated at the PFS of 12 g•min−1 has the best friction reduction and corrosive–wear resistance. The corrosive–wear mechanism of Ni–60%WC coating is combined of abrasive wear, adhesive wear and oxidative wear, which are caused by the hard WC particles and coating porosity.