The second generation of novel cyanide-free alkaline copper plating process was developed based on the first generation of cyanide-free alkaline copper plating process, and the problem of bath stability was successfully resolved. The basic bath composition and operation conditions are as follows: CuSO4·5H2O 25.0 g/L, C6H5O7K3·H2O 0.2 mol/L, assistant complexing agent 0.05 mol/L, stabilizer 0.2 mol/L, activator 0.02 mol/L, H3BO3 30 g/L, KOH 20 g/L, additive 10 mL/L, temperature 45 ℃, pH 8.8-9.2, current density 1.0-1.5 A/dm2, and electrolytic copperas anode. The addition of cuprous stabilizer and activator to plating bath ensures the stable application of the novel process. The influence of bath composition and process conditions on coating properties and current efficiency as well as the anti-impurity performance of the process were studied by Hull cell test and rack plating experiment. The coating obtained under the given process conditions has good properties, therncurrent efficiency is above 90%, and the impurity resistancernof the bath is excellent. The given process is suitable forrncopper pre-plating on steel and copper alloys. The bathrnkeeps stable and the products are qualified after continuousrnuse in production for months.%在第一代钢铁无氰镀铜工艺的基础上,开发出第二代无氰碱性镀铜新工艺,成功地解决了镀液的稳定性问题.镀液的基础配方和工艺条件为:CuSO4·5H2O 25.0 g/L,C6H5O7K3·H2O0.2 mol/L,辅助配位剂0.05 mol/L,稳定剂0.2 mol/L,活化剂0.02 mol/L,H3BO3 30g/L,KOH 20 g/L,添加剂10 mL/L,温度45℃,pH 8.8～9.2,电流密度1.0～1.5 A/dm2,阳极为电解铜.在新工艺镀液中引入一价铜稳定剂和活化离子,保证了其稳定应用.通过赫尔槽和挂镀试验研究了镀液组分和工艺条件对镀层性能和电流效率的影响,以及镀液的抗杂质能力.结果表明,在本工艺条件下,所得镀层性能良好,电流效率高于90％,镀液的抗杂质性能优良.本工艺适用于钢铁、铜合金预镀铜.经数月的连续生产,镀液保持稳定,产品结合力合格.
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