1060铝材两步化学浸锌工艺

Two-Step Elctroless Zinc Plating Process of 1060 Aluminum

铝材化学性质活泼，欲获得不同性能的镀层，前处理非常重要。选用两步碱性化学浸锌体系对1060铝材进行了前处理，随后镀镍。通过自腐蚀电位-时间曲线，浸锌层扫描电镜（SEM）形貌分析，弯折试验、热震试验等考察了浸锌层与铝基体的附着力，并确定了获得结合力优良的浸锌层的最佳工艺条件：300g／L NaOH，65g／LZnO，50g／LKOCO（CHOH）2COONa，1g／LFeCl3，2g／LNaN03；温度20-30℃，一次浸锌时间60s，二次浸锌时间30s，所获浸锌层可满足后续电镀工艺的需要。

1060 Al was pretreated via two-step electroless Zn plating in an alkaline bath,followed by Ni electroplating.The adhesion of the electroless Zn coating to Al substrate was evaluated by measuring corrosion potential-time curve in association with scanning electron microscopic observation,bending test and thermal shock test.The optimized electroless Zn plating bath consisted of 300 g/L NaOH,65 g/L ZnO,50 g/L KNaC4H4O6·4H2O,1 g/L FeCl3 and 2 g/L NaNO3,while the optimized parameters were determined as temperature of 20~30 ℃,time for first electroless Zn plating of 60 s,and time for second electroless Zn plating of 30 s.Resultant electroless Zn coating well met the requirement for follow-up Ni electroplating.