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In this study, nickel matrix composite coatings reinforced by nano WC were prepared by pulse current (PC) electrodeposition. The effects of surfactant sodium dodecyl sulfate (SDS) concentration and wet-milling treatment of WC particles on surface morphologies, distribution of particles, microstructures and microhardness values of Ni/nano-WC composite coatings were all investigated and the results were discussed. The results revealed formation of compact coatings with high contents of embedded WC particles and uniform distribution in presence of SDS and under wet-milling treatment of WC particles. The microhardness of the composite coatings also improved. The optimal coating was obtained by adding 0.15 g/l SDS under wet-milling for 10 h.