The composite processing between laser cladding and low temperature (300?C) ion sulfurization was applied to prepare wear\nresistant and self-lubricating coating.The microstructure, morphology, phase composition, valence states, and wear resistance of\nthe composite coatingwere investigated by scanning electron microscopy (SEM), atomic force microscope (AFM), X-ray diffraction\n(XRD), X-ray photoelectron spectroscope (XPS), and friction and wear apparatus. The results indicate that the laser cladding Nibased\ncoatings and the maximum hardness of 46.5HRC were obtained when the percent of pure W powder was 10%, composed\nof columnar dendrites crystals and ultrafine dendritic structure. After ion sulfurization at 300?C for 4 h, the loose and porous\ncomposite coating is formed with nanograins and the granularity of all grains is less than 100 nm, which consists of y-(Fe, Ni),\nM23C6 carbides, FeS, FeS2, andWS2. Furthermore, the wear resistance of the composite coating is better than the laser cladding\nNi55 + 10%W coating, and the friction coefficient and mass losses under the conditions of dry and oil lubrication are lower than\nthose of laser cladding Ni55 + 10%W coating.
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