Ce 盐封孔对 SiCp/ Al 复合材料表面 Ni-P 镀层的影响

为提高SiCp/Al复合材料的耐腐蚀性能,先化学镀镍,再沉积稀土封孔,讨论了稀土溶液主盐Ce(NO3)3浓度和沉积时间对镍-稀土多层膜耐蚀性能的影响。结果表明:化学镀镍的SiCp/Al复合材料在室温下沉积稀土时,采用Ce(NO3)3含量1 g/L、成膜时间2 h的条件获得的多层膜耐蚀性最好,其腐蚀电位为-0.48mV,腐蚀电流密度为3.54×10-8A/cm2;稀土在膜层中以Ce的氧化物颗粒堆积状态存在,起到了封孔的作用;膜层中的镍磷合金呈多晶态,而稀土含量少,未能测出;稀土溶液浓度越高,沉积速度越快,而在相同浓度下,膜层厚度随着时间的延长而增加,越厚则膜层结合力越差。

Effects of Ce Sealing on Ni-P Coatings for SiCp/ Al Composites Surface

In order to improve corrosion resistance of the SiC_p/ Al composite material, it was treated by electroless Ni plating firstly and then the rare earth coatings were deposited on the surface of it . The effects of the Ce( NO₃)₃concentration of rare earth solution and deposition time on the corrosion resistance of Ni-P coating were discussed. The results show that: Putting the sample into 1 g / L rare earth solution for two hours at room temperature, prepared using the formula, then generate the Nimultilayer corrosion films of rare earth which show the best corrosion resistance. The corrosion potential of the film is-0 . 48 mV, corrosion current density is 3 . 54 X10^-8A / cm². In the films of rare earth Ce-oxides is in the state of oxide particles which accumulate together, the Ce-oxides particles play a key role in sealing process. Ni-P alloy is found in polycrystalline, while due to rare earth is a little in the coatings, none peaks in the XRD. The higher concentration of rare earth, the faster of deposition is,at the same concentration, the thickness increases with time, the greater the thickness of the film, the worse of the adhesion.