| Nanocomposite plating can significantly improve the surface hardness, wear resistance and corrosion resistance. It have many advantages and has been widely used in manufacturing, military, electronics, chemical industry and many other fields. In recent years, Ni-SiC nanocomposite coating has been successfully applied on engine cylinder block, in order to improve the high temperature oxidation resistance of Ni-SiC nanocomposite coating, this paper selected to add SiC Al2O3 particles to Ni-Si C nanocomposite coating, prepared Ni-SiC-Al2O3 nano composite coatings on the surface of 316 L stainless steel substrates, Through the optimization of experimental parameters and the analysis of the results, major conclusions are as follows:The optimal parameters: SiC: 10g/L; Al2O3: 6g/L, current density: 3A/dm2, electroplating time: 20 min, solution temperature: 50℃. After testing and characterization,the results show that:the high content nanoparticles coating has the best resistance to high temperature oxidation. The crystal of the coating preferred orientation（111） crystal plane. The surface of the coating is flat and dense, and the main elements in the coating are:Ni, C, Si, Al, Fe, O;the nano particles are dispersed in Ni base coating.After oxidation experiment, the results shows that the colour of the coating is black gary, and the high temperature oxidation resistance of Ni-SiC-Al2O3 nano composite coating is the best, The high temperature oxidation resistance compared to stainless steel substrate was increased 59.3%; 48.8% higher than pure Ni coating and 38.4% higher than Ni-SiC nanocomposite coating. After oxidation, the surface of Ni-SiC-Al2O3 nano composite coating is still smooth, no bubble or tilt on the surface. The peak of Fe3O4 reduced, it proves that the Ni-SiC-Al2O3 nano composite coating can protect the base metal from oxidation under the condition of high temperature. The high temperature oxidation resistance increased. |
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