中温化学镀镍稳定剂的研究

Study on stabilizers for medium-temperature electroless nickel plating

在由NiSO4.6H2O25g/L、NaH2PO2.H2O30g/L、CH3COONa20g/L、乳酸15mL/L和十二烷基硫酸钠8mg/L组成的中温(75°C)化学镀镍液(pH4.60～4.65)中,研究了不同稳定剂对镀液稳定性、沉积速率、镀层磷含量、镀层性能等的影响。结果表明,低质量浓度(<8mg/L)的硫脲、2-巯基苯并噻唑及Na2S2O3对镀液的稳定效果较好,但适宜的浓度范围较窄,得到的镀层性能较差。KI作为稳定剂时兼有促进剂的作用,可以在较宽的浓度范围内获得相对稳定的沉积速率。金属盐A兼有稳定剂和光亮剂的作用,其加入使镀层光亮、细致。

The effects of different stabilizers on the stability of electroless nickel plating bath mainly composed of NiSO4.6H2O 25 g/L, NaH2PO2·H2O 30 g/L, CH3COONa 20 g/L, lactic acid 15 mL/L and sodium dodecyl sulfate 8 mg/L, as well as the deposition rate, phosphorus content and properties of nickel coating at middle temperature （75℃） and pH 4.60-4.65 were studied. The results showed that low mass concentration （〈8 mg/L） of thiourea, 2-mercaptobenzothiazole or Na2S2O3 can significantly improve the bath stability, but their suitable concentration ranges are narrow, and the properties of nickel coating prepared thereof are relatively poor. KI can not only stabilize the bath in a large concentration range, but also accelerate the deposition. As a stabilizer, metal salt A also serves as a brightener, facilitating the formation of bright and fine- grained coating.