锌镍合金镀工艺优化及镀层耐腐蚀性的研究

Research on Process Optimization of Zn-Ni Alloy Plating and Coating Corrosion Resistance

目的 研究锌镍合金镀层的耐腐蚀性能。方法 通过正交试验法,对锌镍合金电镀工艺进行优化,获得镀液配方。通过中性盐雾试验评判优化后的锌镍合金镀层的耐腐蚀性能,并与镀锌层和镀镉层进行对比。分析主盐、络合剂、p H值、电流密度、温度等对镀层耐腐蚀性的影响。结果 最优配方为：氧化锌6~14 g/L,硫酸镍20~30 g/L,氢氧化钠100~140 g/L,光亮剂4~6 g/L,络合剂50~70 g/L。该配方获得的锌镍合金镀层在中性盐雾实验中,出白锈的时间可以达到720 h以上。结论 锌镍合金镀层的耐腐蚀性优良,优于镀锌层和镀镉层。

Objective To study the corrosion resistance of Zn-Ni alloy coating. Methods By orthogonal test method,the Zn-Ni alloy electroplating technology was optimized,and the plating solution formula was obtained. The corrosion resistance of the optimized Zn-Ni alloy plating was evaluated by neutral salt spray test,and compared to those of the galvanized layer and cadmium plating layer. The influence of the main salt,complexing agent,p H value,current density and temperature on the coating corrosion resistance was analyzed. Results The optimal formula was： zinc oxide 6 ~ 14 g / L,nickel sulfate 20 ~ 30 g / L,sodium hydroxide 100 ~140 g / L,brightener 4 ~ 6 g / L,and complexing agent 50 ~ 70 g / L. The Zn-Ni alloy coating obtained using this formula had a white rust occurrence time of more than 720 hours in the neutral salt spray test. Conclusion The Zn-Ni alloy coating had excellent corrosion resistance,superior to those of zinc and cadmium plating layer.