Effects of Plasma Arc Surfacing Current on Microstructure and Wear Resistance of High Vanadium Fe-based Surfacing Coating

High vanadium Fe-based surfacing coating was prepared by plasma arc surfacing technology. The effects of plasma arc surfacing current on phase composition, microstructure, hardness and wear resistance of high vanadium composite Fe-based surfacing coating were studied by scanning electron microscope（SEM）, multifunctional stereomicroscope, energy spectrum（EDS）, X-ray diffraction（XRD）, hardness tester and wear tester, respectively. The results show that the surfacing current has a great influence on the microstructure and comprehensive mechanical properties of the coating and the main crystalline phases of the surfacing coating are martensite, VC and M₇C₃-type eutectic carbide. Small spherical VC particles with dispersive distribution in martensite matrix and（Fe, Cr, V）₇C₃ eutectic carbide form a wear-resistant skeleton. The alloy surfacing coating prepared at 160 A of surfacing current has better comprehensive mechanical properties, with 63.3（HRC） of surface hardness and 0.042 7 g of wear capacity for the surfacing coating.