超声振荡辅助化学镀镍及其性能研究

将超声振荡方法引入化学镀镍工艺以降低化学镀温度,提高沉积速率,并对中温化学镀镍工艺进行了初步探讨。通过正交试验,确定了最佳基本镀液配方及操作条件为:NiSO4·6H2O 25g/L,NaH2PO2·H2O 25g/L,CH3COONa 25g/L,H3BO3 15～25g/L,硫脲2g/L,pH5.8,温度55°C。借助于扫描电镜、X射线衍射、能谱、硬度及塔菲尔曲线等测试方法,对镀层进行了表征。结果表明,超声振荡方法所得镀层的耐腐蚀性能和硬度均明显优于常规水浴法;加入稳定剂硫脲不仅可提高镀速,还可明显改善镀层外观及耐腐蚀性。

Study on ultrasonic-assisted electroless nickel plating and performance of deposit

An ultrasonic agitation method was used in electroless nickel plating to decrease the electroless plating temperature and increase the deposition rate. The mediate-temperature electroless nickel plating technology was preliminarily studied. The optimal plating bath formulation and operation conditions were determined through orthogonal experiment as follows: NiSO_4·6H_2O 25 g/L, NaH_2PO_2·H_2O 25 g/L, CH_3COONa 25 g/L, H_3BO_3 15-25 g/L, thiourea 2 g/L, pH 5.8, and temperature 55 ℃. The deposit was characterized by scanning electron microscopy, X-ray diffraction, energy-dispersive spectroscopy, hardness testing and Tafel polarization curve measurement. The results indicated that the deposit prepared by ultrasonic-assisted electroless plating method has higher corrosion resistance and hardness than that prepared by normal water bath method. The addition of thiourea as stabilizer can not only increase the deposition rate, but also improve the appearance and corrosion resistance of deposit.