【摘要】 研制了一种新型镁合金的无Cr阳极氧化配方 ,对镁合金进行阳极化处理 .溶液的主要成分为NaOH、NaSiF6和有机添加剂 .XRD、SEM、XPS测试结果表明 ,氧化膜主要由MgO、MgAl2 O4 和 2Al2 O3 ·2SiO2 ·H2 O组成 .3 5 %NaCl水溶液动电位极化结果说明 ,氧化膜有良好耐点蚀性能 .合金中Si、Al元素的氧化弥补了Mg氧化时的体积收缩 ,氧化膜无裂纹 ,为其耐点蚀提供了条件 .阳极化后Al、Si元素在表面均匀分布 ,是氧化膜具有良好保护作用的原因之一 .更多还原

【Abstract】 A suitable mixture without chromium is developed for protection of magnesium alloys by treatment with the anodic oxidation.The aqueous solution is composed of NaOH、Na 2SiF 6 and an organic additive.The potentiodynamic polarization measurement showed that the film had outstanding protective ability in 3.5% NaCl solution.The morphology and component of the anodic oxidation film have been analysed by SEM,XRD,XPS and EPMA respectively.XRD and EPMA analysis revealed that the film was made of MgO、MgAl 2O 4 and 2Al 2O 3·2SiO 2·H 2O.Si and Al oxides make up the volume shrinkage of magnesium oxides,so that the film has no crack which provides a good condition against pitting.And the even dispersions of Si and Al in the film is another factor that the film has better protection.更多还原