镀锡铁基体的化学镀铜

为了提高铁的耐蚀性,在镀锡铁基体上进行了化学镀铜的研究。系统地研究了柠檬酸-酒石酸二元配位体化学镀铜体系中各因素对镀速的影响。结果表明,柠檬酸-酒石酸二元配位体系的镀速大于柠檬酸单配位体系的镀速。随着CuSO4.5H2O、柠檬酸、酒石酸、次磷酸钠浓度的增大,以及随着pH和温度的升高,镀速均先升高后降低。化学镀铜液的最佳组成为：CuSO4.5H2O 12 g/L,柠檬酸40 g/L,酒石酸40 g/L,次磷酸钠20 g/L,抗氧化剂1 g/L,硼酸10 g/L,表面活性剂0.1 g/L。最佳温度为55～60℃、pH为1.25～1.76。在最佳条件下,铜的镀速为5.06μm/h,获得的镀层表面光亮平滑,结晶致密,耐蚀性良好。铜锡镀层之间、锡镀层与铁基体之间的结合力优良。

Electroless Copper Plating on the Tin-Plated Iron Substrate

In order to improve the corrosion resistance of iron,the electroless copper plating was studied on the tin-plated iron substrate.In the citric acid-tartaric acid binary ligand electroless plating copper system,the influences of factors on the deposition rate were systematically investigated.The results indicated that the plating rate in the citric acid-tartaric acid binary ligand system was greater than that of in the citric acid mono ligand system.With increase of concentration of CuSO4？5H2O,citric acid,tartaric acid,sodium hypophosphite,and with rise of pH value and temperature,the deposition rate were first increased and then decreased.The optimal composition of electroless copper plating bath was suggested to be composed of CuSO4？5H2O 12 g/L,citric acid 40 g/L,tartaric acid 40 g/L,sodium hypophosphite 20 g/L,antioxidants 1 g/L,boric acid 10 g/L and surfactant 0.1 g/L.The optimized temperature and pH value was 55～60 ℃ and 1.25～1.76,respectively.At the optimized conditions,the copper deposition rate was 5.06 μm/h.The surface of the obtained deposit was bright and smooth,the crystal was compact.The corrosion resistance of the coating was good.The adhesion between the deposits of copper and tin,and that of between tin and the iron substrate are superior.