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The microstructure and tensile binding strength of Ni-based self-lubricating coatings PS304 by plasma spraying and PM304 by powder metallurgy were studied. The result shows that the PS304 coating prepared by plasma-spraying has a coarse microstructure and high porosity. The lubricant phase fluoride and strengthening phase Cr2O3 are distributed unevenly. However, the microstructure of PM304 coating prepared by mechanical milling and vacuum sintering is uniform and dense, and the size of particles is much finer. The tensile test shows that the PS304 coating has a low tensile binding strength. The tensile fracture occurs not only in the interface of coating and substrate, but also appears in the internal of the coating. The PM304 coating has a higher tensile binding strength, and a good metallurgical bonding can be obtained between coating and substrate. The tensile fracture mainly appears in the internal of the coating. The higher tensile binding strength of PM304 coating is mainly due to 4 reasons, including the increase of density, the decrease of the sharp pores number, a metallurgical bonding formed between Ag and NiCr, and the dispersion hardening effect of fine particles precipitated from the NiCr substrate which increases the strength of the NiCr substrate.