Preparation of Ni-Coated SiC Ceramic Composite Powder by Electroless Plating
As a surface technology, electroless plating is applied to almost every industry branch. To improve the wettability of SiC powder and metal, the surface of SiC powders was plated with a Ni plating in the basic solution according to the reaction theory of electroless plating. The main salting was nickel chloride, and the reducing agent was hydrazine hydrate. The plating velocity, phase transformation and microstructurewere investigated using XRD and SEM. The results show that the SiC powders had no increasing weight and no reaction can occur when the pH below 8.5. when the pH value was between 10 and 11, the weight gain of powders closed to the theoretical value, the Ni peaks in X-ray diffraction patterns of powders was relatively strong, the SiC coating surface was composed of granular, cellular and globe-like Ni, the substrate was covered of Ni plating completely. When the pH value was above 11, the gas production was becoming more pronounced and the reaction speed increasing with the increased of the pH value, the time from deep blue to colorless of solution started to drop off, the Ni(OH)2 peaks in X-ray diffraction patterns of powders have already begun to emerged and a small amount of nickel films was generated.
Huixuan Zhang, Ye Han, Fuxiao Chen and Jiuba Wen
H. Yao et al., "Preparation of Ni-Coated SiC Ceramic Composite Powder by Electroless Plating", Applied Mechanics and Materials, Vols. 117-119, pp. 77-80, 2012