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The nickel-based BaF2-CaF2 composite coating was fused onto the H13 substrate using laser melting technology. The morphology, microstructure and phase composition of the molten layers were observed and determined using scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive spectrometer (EDS) and metallographic microscopy. The friction and wear properties of the coatings were tested and analyzed using a friction and wear tester, and the friction and wear behavior and lubrication mechanisms of the coatings at high temperatures were investigated. The results showed that the microhardness of the clad layer decreased with the increase of BaF2-CaF2 content, and the average microhardness of the clad layer was 547.61 HV. The clad layer with 92% Ni60+8% BaF2-CaF2 composite powder had the best quality and showed good friction reduction and anti-wear effect in the test high temperature range, and the friction coefficients were all below 0.25, and the wear rate was 67.9% less than that of the substrate. The wear rate was reduced by 67.9% compared with that of the matrix. It benefits from the enhancement of the Ni-based powder and the selflubricating properties exhibited by BaF2-CaF2 at high temperatures as well as the synergistic lubricating effect of the large amount of oxides generated by friction.
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