无铬磷酸盐稀土转化膜工艺研究

Study on Chromium-Free Phosphate Rare Earth Conversion Coatings Technology

常温下对6061铝合金表面转化膜进行了研究,分别讨论了Zn2+、PO43-、F-、Fe2+、Ce3+、Cu2+对磷化膜质量的影响,同时通过正交试验和综合评定法确定出了一种不含铬的铝合金稀土磷化液的介质组成及相应的工艺参数。转化膜成分含有Zn、Fe、P、O、Ce的复合磷酸盐,结果表明:此磷化液在常温下,8 m in即可在6061铝合金表面上生成一层均匀、致密、耐蚀性良好的磷化膜。该方法工艺简单,在整个工艺过程中不需要使用铬元素,对环境影响小,具有良好的应用前景。

Conversion coating on 6061 aluminum alloy surface has been studied under ordinary tempera- ture. The effects of Zn2＋、PO4 3-、F-、Fe2＋、Ce3＋、Cu2＋ on the quality of phosphating coating were dis- cussed. In addition, by use of orthogonal experiment and synthetic evaluation method, the composition and corresponding process parameters of a chromium -free rare earth phosphating solution are determined. The conversion film conponent contains compound phospates of Zn, Fe, P, O, Ce. The results show that this phosphating solution at room temperature can form a uniform, dense and corrosion protective layer in 8 min on 6061 aluminum alloy surface. This method is simple, and needs no chromium element completely, with less harmful effects on environment and good application prospect.