碱性锌酸盐体系锌钴合金电镀工艺研究

Study on Electroplating Processes of Zinc-Cobalt Alloy Coatings in Alkaline Zincate Solution

目前国内对碱性锌酸盐体系电镀锌钴合金的研究较少。研究了碱性锌酸盐Zn-Co合金电镀体系中合金镀液组成及工艺条件对镀层Co含量的影响,得到了最佳镀液组成及工艺条件:锌钴离子总浓度0.3 mol/L,锌钴离子摩尔比9∶1,150 g/L氢氧化钠,15.0 m L/L添加剂A,1.0 m L/L添加剂B,电流密度Jc3 A/dm2,温度25~30℃。在最佳工艺条件下可得到Co含量为2.0%~2.2%的Zn-Co合金镀层。结果表明:Zn-Co金的沉积表现为异常共沉积;在一定范围内,镀层中钴含量的变化会影响镀层光亮度的变化;钴配位剂对Zn-Co合金的共沉积电化学行为不造成影响。

Process of Zn- Co alloy electroplating in alkaline zincate solution was studied,and the ingredients of the alloy electroplating solution and the process parameter as well as their relationship with the Co content in the alloy coating were investigated.Results showed that the optimum process was as follows;total concentration of zinc and cobalt ions was 0.3 mol/L,the mole ratio of zinc and cobalt ions 9:1,NaOH 150 g/L,additive A 15.0 mL/L,additive B 1.0 mL/L,current density 3 A/dm^2,operating temperature 25~30 ℃.Under the optimum conditions,the Zn- Co alloy coating with 2.0%~ 2.2%Co was obtained.The Zn-Co alloy electrodeposition belonged to anomalous codeposition.Within a certain range,the optical brightness of the coating was improved with the increase of Co content in the coating,while cobalt complexing agent did not affect electro-chemical behavior of ZnCo alloy codeposition.