镍-碳化钨复合电镀工艺优化及镀层耐蚀性

摘要

Ni-WC composite coating with excellent corrosion resistance was obtained on the surface of copper substrate by composite electroplating.The optimal bath composition and process conditions obtained by orthogonal test are as follows:NiSO4·6H2O 250-300 g/L,NiCl2·6H2O 40-50 g/L,WC particles 35 g/L,H3BO3 35-40 g/L,sodium dodecyl sulfate 0.05 g/L,current density 3 A/dm2,temperature 40℃,magnetic stirring,and plating time 4 h.The Ni-WC composite coating obtained under the optimal conditions contains 29.95wt％ WC and has a thickness of 103.0 μm.There is no red rust on the Ni-WC composite coating surface until 120 h of neutral salt spray test,showing a much better corrosion resistance than the pure Ni coating which endures only 96 h for red rust in NSS test.%采用复合电镀工艺在铜表面制备了耐蚀性优良的Ni-WC复合镀层.通过正交试验对工艺条件进行优化,得到的最佳配方和工艺为:NiSO4·6H2O 250～300 g/L,NiCl2·6H2O 40～50 g/L,WC微粒35g/L,H3BO3 35 ～ 40 g/L,十二烷基硫酸钠0.05 g/L,电流密度3 A/dm2,温度40℃,磁力搅拌,时间4h.最佳工艺条件下,所得Ni-WC复合镀层的WC质量分数为29.95％,厚度为103.0 μm,中性盐雾试验中出现红锈的时间为120h,耐蚀性远优于纯Ni镀层(耐红锈时间96h).