Microstructure and property of Ni60A/WC composite coating fabricated by fiber laser cladding

Abstract

Laser clad Ni60A/WC composite coating was fabricated on the surface of Q235 steel by using 6 kW fiber laser. The morphology, composition, and microhardness of composite coating were studied by using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X‐ray diffraction (XRD), and micro‐hardness tester. The results show that in the process of fiber laser cladding Ni60A/WC composite coating, residual WC particles partially dissolve and react with other elements to form eutectics, which exists in the shape of lumpy, strip and spherical. The main structures of laser cladding are γ‐Ni, WC, W 2 C, M 7 C 3 , M 23 C 6 etc. From the hardness analysis, the average hardness of the composite coating is four times of the substrate.