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A nickel-based composites coating reinforced by TiB2+WC has been prepared on stainless steel by laser cladding.The Microstructure is composed of γ-Ni dendrite and dispersed fine TiB2 and WC particles.In the upper part of the coating,the white phase dispersed in the coatings is mainly fine batt-shaped TiB2 particles.In the middle and bottom parts,the white phase is mainly composed of comparatively coarse equiaxial WC particles,only a small amount of fine TiB2 particles are present.The different distribution of TiB2 and WC should be attributed to the density difference of TiB2,WC and Ni-based alloys and the comparatively slow scanning rate.The microhardness gradually increases from the bottom to the top of the coating due to the different distribution of TiB2 and WC.The thermal shock experiments show that no cracks were observed throughout the whole coating,especially in the interface,which demonstrates that the coating has a good metallurgical bond with the substrate and processes excellent resistance to cracking due to the formation of some intermetallics in the interface and homogeneous distribution of the fine reinforcement phases WC and TiB2 in the matrix.