铝阳极氧化膜极限厚度的研究及氧化膜微观结构的表征

采用恒电压电解法研究了铝在硫酸中的阳极氧化过程.通过金相显微镜、扫描电镜(SEM)观测了铝阳极氧化膜的厚度和微观结构特征,并通过X射线能谱仪(XPS)分析了氧化膜的成分.结果表明:长时间氧化后,氧化膜厚度达到一个极限值,此值与外加电压、电解液浓度及温度有关;铝试样本身存在缺陷时,对氧化膜的制备产生一定的影响;阳极氧化膜的主要成分为Al和O,并含有杂质元素S.

Limit Thickness of Aluminum Anodic Oxidation Film and Its Microstructure

The anodic oxidation process of aluminum in sulfuric acid was investigated using constant voltage electrolysis method. The thickness and microstructure of the aluminum anodic oxidation film were analyzed using an optical microscope and a scanning electron microscope, while the elemental composition of the film was determined using an energy dispersive X-ray analyzer. It was found that the thickness of the Al anodic oxidation film reached a limit maximum after long enough electrolytic oxidation, and the value of the limit thickness of the film was related to the voltage and the concentration and temperature of the electrolyte. The defects such as pores and cracks in the Al substrate had some effect on the anodic oxidation behavior, and the Al anodic oxidation film was mainly composed of Al and O and a little amount of impurity S.