无氰与有氰浸锌溶液性能比较

Performance Comparison of Cyanide-Free Zincation Solution and Cyanide-Contained Zincation Solution

浸锌是铝件各种电镀前处理方法中最简便、经济、使用最广的工艺。为取代浸锌溶液中的氰化物络合剂,在对不同络合剂组合进行大量研究的基础上,优选出 4种无氰浸锌溶液与商品化有氰浸锌溶液做性能对比试验,内容包括浸锌层微观形貌及组成成分、浸锌层在 3.5%NaCl溶液中腐蚀后的表面形貌及腐蚀速率,并测试了浸锌过程中的时间- 电位曲线和浸锌层在 3.5%NaCl溶液中塔菲尔极化曲线,还用拉伸试验机定量测试了镀层结合力。结果表明,有 1种无氰浸锌溶液性能优于有氰浸锌溶液,有 2种无氰浸锌溶液性能接近有氰浸锌溶液。

Zincation process is the simplest,most economy and widest application process used in pretreatments in electroplating aluminium parts.In order to substitute the cyanide complexing agent in the zincation solution,based on a lot of study on different complexing agent combinations,4 better cyanide-free zincation solutions are selected to compare with commercial cyanide-contained zincation solution for their performances,including micromorphology,components of the zinc deposit and the surface morphology and corrosion rate of zinc layer in 3.5% sodium chloride solution. Also the variations of zincating potential with the change of zincating time (E-t curves) and Tafel polarization curves are measured in 3.5% sodium chloride solution by electrochemical testing system.And the adhesion of the consequent deposit on zinc layer is measured quantitatively with tension test.The results show that the performance of cyanide-free zincation solution is better than that of cyanide-contained zincation solution;and the performances of two cyanide-free zincation solutions are similar to that of cyanide-contained zincation solution.