摘要
采用高频脉冲电源，在镍钴合金衬底上添加SiC，探索制备镍钴合金碳化硅镀层的最佳条件。较佳工艺条件为：频率80kHz，平均电流密度3A／dm^2，占空比0．24，温度为40摄氏度，添加剂为0．5g／L煮沸30min的十二烷基硫酸钠与1g／L糖精钠。通过SEM、XRD测试结果分析高频脉冲各条件对镀层性质的影响原因，研究了脉冲频率、占空比、电流密度、SiC及添加剂对镀层结构、耐腐蚀性的影响。相比相同条件下未添加SiC的镍钴合金镀层，高频脉冲镀层的孔隙率较低，表面致密均匀，耐腐蚀性较好，高频脉冲电镀Ni-Co／SiC合金镀层的耐腐蚀性随着频率的升高而显著增强。
SiC composite coatings on Ni-Co alloy were prepared by a high frequency of 20 kHz-140 kHz, and the best conditions for preparing Ni-Co/SiC composite coatings were investigated. The experiment found that the optimal conditions were as follows： frequency 80 kHz, average current density 3A/dm2, duty ratio 0.24, temperature 40 degrees Celsius. Additives are 0.5g/L of boiling THF 30min and lg/L sodium saccharin. Pulse plating of Ni-Co/SiC composite coatings were investigated and the effects of pulse parameters, i.e. pulse frequency,duty ratio and frequency on the coating structure, corrosion resistance of these coatings were investigated. The influences of high-frequency pulse conditions on the properties of Ni-Co/SiC composite coatings were analyzed by SEM, XRD test results. Compared with Ni-Co alloy composite coatings prepared under the same conditions, Ni-Co/SiC composite coatings have more compact and uniform surface as well as lower porosity and good corrosion resistance. The coating corrosion resistance of Ni-Co/SiC prepared in highfrequency pulse plating was enhanced significantly with increasing operating frequency.
