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The Ni-based alloy coatings reinforced with TiN-TiB2 were prepared on AISI302 stainless steel by reactive plasma cladding process. The effects of reactants proportion on the microstructure and microhardness of the coatings were investigated in detail by means of optical microscope, scanning electron microscope (SEM), X-ray diffraction (XRD), Energy Dispersive Spectrometry (EDS) and microhardness tester. The results show that the reinforcement phases of TiN-TiB2 are successfully in situ synthesized in the coatings. The ceramic reinforcement phases evenly disperse in the metal matrix of the coatings. The microhardness of the Ni-based alloy coatings reinforced with TiN-TiB2 is far higher than that of AISI302 steel substrate. With the increase of the proportion of Ti+h-BN in the reactive powders, the microhardness of the clad coatings gradually increases. Once the proportion of Ti+h-BN in the reactive powders is more than 25wt.%, it has no obvious effect on the microhardness of the clad coatings.