镀锌板表面有机硅烷-磷化复合膜与阴极电泳漆膜配套性研究

The Performance of Silane--Based Phosphate Composite Film and the Compatibility with Cathodic Electrodeposition Coating in Galvanized Sheet Surface

本文介绍了一种可以满足阴极电泳涂装要求的有机硅烷化的磷化处理液，对有机硅烷化的磷化转化膜进行电化学、耐碱性、溶出率、硫酸铜点滴测试，结果显示当有机硅烷和磷化成分配比为8：2时，其耐蚀性最好。通过分析入槽前干膜和湿膜的电化学等性能，发现无论是湿膜或干膜在一定条件下均能得到均一致密的膜层。讨论不同电泳电压、电泳时间对膜厚以及膜外观的影响，当电泳电压为150V、电泳时间为120s时，可形成性能优异的电泳漆膜。

This article reports a silane--based phosphating agent that may match with requirements of the cathodic elec- trodeposition coating in galvanized sheet surface. Different surface analysis tests were conducted to evaluate the anticorrosive a- bility of the formed saline--based phosphating film： electrochemical impedance spectroscopy （EIS）, alkali resistance, disso- lution rate, copper sulfate spot testing. The results suggest that the silane--based phosphating agent acquires the optimal cor- rosion resistance when the proportioning of silane--based phosphating agent is 8 ： 2. The EIS of dry and wet films were analys- ized be{ore dipping into tank and found that wet film had no significant difference with dry film under certain condition to form a dense and homogeneous cathodic electrodeposition coatings. The influence of the film thickness and appearance at different electrodeposition voltage and electrodeposition time were discussed and it was found that obtained the excellent performance of electrodeposition coating when the desired electro-- deposition voltage is 150V, electrodeposition time is 120s.