丙二酸溶液中的铝阳极氧化研究

在丙二酸电解液中进行了铝阳极氧化，并采用扫描电镜（SEM）、X射线衍射（XRD）及显微硬度仪对氧化膜的构型、物质结构、耐酸性、显微硬度等进行了表征。结果表明，丙二酸电解液的黏度随浓度的升高而增大，电解液黏度较大时，氧化膜的生长速率会明显降低；电流密度较大、氧化时间较长时能显著提高氧化膜构型的规整度；氧化膜膜厚的增长速率呈现出先增大后降低的规律；在相同的氧化条件下，电解液浓度较大时，得到的氧化膜的厚度也较大。在800℃以上对丙二酸氧化膜加热，原来无定型的氧化铝会结晶生成γ-Al₂O₃；氧化膜结晶后其耐酸性会显著提高。丙二酸电解液的浓度对氧化膜的显微硬度没有显著影响，氧化膜硬度对膜厚的依赖存在一个极限值，约为27μm。

Aluminum anodization in malonic acid electrolyte

Anodic aluminum oxide (AAO) films have been prepared in malonic acid electrolytes. The film morphology, crystalline structure, and resistance to acidic dissolution were studied by scanning electron microscopy (SEM), X-ray diffraction (XRD), and the hardness was investigated by micro-hardness testing. It was found that the electrolyte viscosity increased with increasing concentration and that higher electrolyte viscosities resulted in a marked decrease in film growth rate. When applying high current densities for long anodizing durations, AAO films with a relatively high degree of order can be produced. The growth rate of the film layer initially increased and then decreased gradually; under similar anodizing conditions, thicker film layers were formed with higher electrolyte concentrations. The amorphous film material was transformed into γ-Al₂O₃ by heat-treatment above 800℃ and the resistance to acid dissolution increased remarkably when the AAO film was crystallized. The electrolyte concentration had no evident effect on film hardness and the film hardness attained a relatively stable value when the film thickness was increased to about 27μm.