在镁合金阳极氧化膜上的化学电泳涂装

将AZ31B镁合金放入氯化钠溶液中进行简单的阳极氧化后形成一层高活性的氧化膜,再通过化学电泳涂装形成复合涂层.利用氯化钠溶液的浸泡、电化学极化、交流阻抗、SEM等测试方法对涂层外观及耐蚀性进行表征.结果表明,简单阳极氧化膜在350℃的温度下脱水活化40min后,可以形成高活性的氧化涂层,表面粗糙度、亲水性和碱度大有改进,与电泳漆的反应活性大.阴极聚氨酯电泳漆进行化学电泳涂装获得的复合涂层漆膜厚、疏水性好、耐蚀性高.

Electroless E-coating on Anodic Oxidation Film of Magnesium Alloys

AZ31B magnesium alloy was put in NaCl solution to produce a highly active oxide film through simple anodic oxidation.Afterwards,a composite coating was fabricated via application of electroless cataphoresis.The morphology and corrosion resistance of the composite coating were characterized by the images of scanning electronic microscope,electrochemical polarization curves, electrochemical impedance spectra and hydrogen evolution volume after immersion test in NaCl solution.The results show that a highly active oxide film was formed after the simple oxide film as prepared was dehydrated at 350℃ for 40min.The cured anodic oxide film had cruder surface.The hydrophily and alkalinity was greatly improved so that it had the great activity of reaction with the cathodic electrophoretic paint.The thicker composite E-coating was obtained through application of electroless cataphoresis in a cathodic polyurethane paint and had super hydrophobicity and good corrosion resistance.