低含量钴对镍合金镀层结构和性能的影响

研究了低含量的钴对镍合金镀层结构和性能的影响,通过扫描电镜观察了镀层形貌、X射线衍射仪测量了镀层内应力,并用电化学极化曲线和腐蚀失重方法分析了镀层的耐蚀性.结果显示:镀液中硫酸钴的含量为0～4 g/L内时,随着钴盐的加入,镍合金镀层结晶细化、结构紧密、耐蚀性和硬度提高,内应力缓慢增长;硫酸钴含量超过5 g/L后,镍合金镀层结晶不再继续细化,但拉伸内应力明显变大,耐蚀性开始降低.

Effect of Low-Content Cobalt on Structure and Performance of Nickel Alloy Electroplating

Effect of different amount of cobalt on nickel alloy electroplating was investigated by means of SEM,XRD,electrochemical polarization curve and corrosion weight loss methods.Results indicate that the with the increase of cobalt sulfate content among 0 and 4 g/L in the bath,the crystalline of deposit is fining,structure is compact,the microhardness and corrosion resistance is improved,and inner stress increases slowly.However the amount of cobalt sulfate is over 5 g/L,the crystalline of nickel alloy plating is not keeping on fining,and the tensile internal stress increases obviously and the corrosion resistance begins to decrease.