One-step pickling-activation before magnesium alloy plating

• Published in: Transactions of Nonferrous Metals Society of China Vol. 19; no. 2; pp. 504 - 510
• Main Author: 王新娟 余刚 欧阳越军 何晓梅 张俊 叶立元
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.04.2009; Department of Chemistry and Chemical Engineering, Huaihua College, Huaihua 418000, China%Department of Chemistry and Chemical Engineering, Hunan Institute of Technology, Hengyang 421002, China; State Key Laboratory of Chemo/Bisensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China%State Key Laboratory of Chemo/Bisensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China
• Subjects: corrosion resistance; electroplating; magnesium alloy; pickling-activation; pretreatment; X射线衍射; 合金电镀; 激活过程; 表面预处理; 镁合金; 预处理方法; 高锰酸钾溶液; pickling-activation; magnesium alloy; electroplating; corrosion resistance; pretreatment
• ISSN: 1003-6326
• DOI: 10.1016/S1003-6326(08)60303-9

A one-step pickling-activation process was proposed as an environmental friendly pretreatment method in phosphate-permanganate solution before electroplating on magnesium alloys. The effects of pickling-activation on qualities of coating were assessed by adhesion and porosity testing of copper plating. The interfacial reactions between specimen and solution were analyzed with SEM, EDX and XRD. The results show that the developed process of pickling-activation can equalize the potentials on substrate surface. The compacted zinc film can be obtained by zinc immersion after treating magnesium alloy in the pH 4-6 phosphate-permanganate solution for 3-5 min. The adhesion and corrosion resistance of copper plating are enhanced. The one-step pickling-activation can replace the existing two-step process of acid pickling and activation which contains a great deal of chromium and fluorine. The procedure of surface pretreatment is simplified and the production environment is improved.