作　　者： ; ; ; ; ;

机构地区： 广东工业大学材料与能源学院

出　　处： 《材料保护》 2011年第10期19-22,7,共4页

摘　　要： 为提高锌铝涂层的耐蚀性能,在硅烷钝化液体系基础上,加入不同含量的稀土镧盐制备锌铝涂层。采用SEM、EDS、NSS、EIS和极化曲线等方法评价了涂层的结构与性能,研究了不同稀土镧盐含量对涂层的钝化作用。结果表明:添加7 g/L稀土镧盐的涂层耐蚀性能最好,为不加稀土镧盐的2倍;适量的稀土镧盐能改善涂层结构,使涂层均匀致密;稀土镧盐钝化处理能显著降低涂层的腐蚀电流,提高腐蚀电位,抑制腐蚀速率,提高涂层的耐蚀性能。 Rare earth lanthanum salt was added into passivation bath of silane system,and resultant bath was used to prepare water-borne Zn-Al coating.The microstructure and composition of as-prepared Zn-Al coating were analyzed by means of scanning electron microscopy and energy dispersive spectrometry.The corrosion resistance of the coating was evaluated by making use of neutral salt-spray test,electrochemical impedance spectroscopy and polarization curve method,and the effect of the content of rare earth La salt on passivation of the Zn-Al coating was examined.It was found that La salt was able to effectively improve the corrosion resistance of Zn-Al coating, and the coating incorporated with 7 g/L La salt had the best corrosion resistance.Besides,the introduction of a proper amount of La salt helped to improve the structure of the coating and increase its uniformity and compactness.In the meantime,La salt was able to cause prominent passivation of the coating and retard its corrosion,leading to significantly reduced corrosion current and gready increased corrosion potential.

关 键 词： 锌铝涂层 钝化 稀土镧盐 硅烷 极化曲线 电化学阻抗 结构 耐蚀性能

领　　域： [金属学及工艺] [金属学及工艺]