Microstructure and Hardness of Fe-Based Alloy Coating Reinforced with WC on Q235 Steel Surface by Plasma Cladding

By plasma cladding technology a Fe-based alloy coating reinforced with 50wt% Ni coated WC was prepared on the substrate of Q235 steel.The microstructure of the coating was investigated by SEM,EDS and XRD.The microhardness distribution of the coating was tested by microhardness tester.The results show that the coating was about 2.6 mm in thickness without cracks and gas pores.The WC particles in the alloy coating were partly melted into the Fe-based alloy,and the reaction layer with the thickness of several microns was formed at the interface between WC and coating.The microstructure of the reaction layer was mainly composed of γ-Fe matrix with the strengthening phases of Cr23C6,Fe3W3C,WC and Ni3B.The microhardness of the coating could reach 700-1 100 HV.