热镀锌层上改进型硅烷膜的耐蚀性能

ANTI-CORROSION PERFORMANCE OF THE MODIFIED SILANE FILMS ON HOT-DIP GALVANIZED STEEL

采用添加钼酸盐和磷酸盐的改进型硅烷溶液处理热镀锌钢板,应用俄歇电子能谱(AES)技术分析了膜层中元素的分布。结果表明,改进型硅烷膜为双层结构,外层是较厚的C-Si-O,内层是Mo-P-O-Zn复合物。通过中性盐雾实验(NSS)、极化曲线和电化学交流阻抗谱(EIS)研究了膜层的耐蚀性能。结果显示,该膜层的耐蚀能力接近于铬酸盐钝化膜,是替代传统铬酸盐钝化的良好选择。

Hot-dip galvanized steel samples have been treated in a solution containing molybdate, phosphate and silane. The distribution of the elements in the coating layers has been determined using Auger electron spectroscopy （AES）. The corrosion resistance of the treated samples has been compared to that of bare samples after exposure to 5% NaCl solution using polarization curves and electrochemical impedance spectra （EIS） data. The samples have also been exposed to the salt spray test. The results of these tests suggest that the modified silane coating layer is composed of an outer C-Si-O rich layer and an inner Mo-P-O-Zn rich layer and it is a promising candidate for replacing conventional chromate treatments.