乙内酰脲无氰电镀金工艺

Technology for Cyanide-Free Gold Electroplating in the Presence of Hydantoin as Complexing Agent

为消除氰化物镀金的危害,提出并研究了以乙内酰脲为配位剂的无氰电镀金工艺。采用扫描电子显微镜(SEM)、原子力显微镜(AFM)对金镀层表面形貌进行观察,采用热震试验测试金镀层结合力,采用硝酸试验测试金镀层的耐蚀性。结果表明:控制金盐10 g/L与乙内酰脲100 g/L左右,并加入复配添加剂(0.05 g/L C+0.1mL/L D),镀液无毒、稳定性良好,在阴极电流密度3 A/dm^2,温度40℃下电镀10 min,可得到结晶致密、光亮的金镀层;镀层与镍基体结合牢固,具有良好的耐蚀性。本工艺有望取代氰化物电镀金,具有广阔的应用前景。

A novel gold electroplating technology using hydantoin as the complexing agent was investigated so as to get rid of hazardous cyanide in conventional gold electrodeposition process.The surface morphology of the coating was observed using a scanning electron microscope and an atomic force microscope.The adhesion to substrate and corrosion resistance of as-prepared Au coating were evaluated based on thermal vibration test and nitrate dipping test respectively.Results show that the electroplating bath composed of 10g/L gold salt,about 100g/L hydantoin,combinatory additives of 0.05 g/L C plus 0.1 mL/L D is non-toxic and has good stability.Resultant electroplating bath could be well used to prepare uniform and bright Au coating at a cathodic current density of 3 A/dm^2, temperature of 40℃and duration of 10 min.As-obtained Au coating had good adhesion to substrate and good corrosion resistance as well.The established cyanide-free Au electroplating process may be adopted to replace cyanide-based Au electroplating process,showing promising application.