硫酸盐三价铬电镀新体系的研究

Study on a new system of sulfate trivalent chromium plating

研究了一种全硫酸体系的三价铬电镀工艺,并对该体系的镀液和镀层进行了性能测试。测试结果显示,该体系无需陈化镀液即可正常工作,所得镀层外观光泽明亮,光亮范围可从4A/dm2至25A/dm2以上;镀液的pH值容易控制,无需调整就能在最佳pH值范围内工作;直角阴极法测试所得覆盖能力可达90%;Tafel测试和NSS试验表明,三价铬镀铬层具有较好的耐蚀性,较六价铬镀层略差,需要进一步改善。

A full of sulfuric acid system of Cr3＋ plating process is studied, the solution and the coating performance test is carried out. The test results show that the system can work normally without bath solution, the coating has exterior burnish bright, shining range from 4 to 25 A/dm2. The solution pH value can be easily controlled, and can work in the best pH range without adjustment. By orthogonal test method, ability to cover the cathode can reach 90%. Through the Tafel test and NSS test, the corrosion resistance of Cr3＋ plating chromic layer is slightly less than that of Cr6＋ plating, and need to be further im- proved.