陽極酸化皮膜の二次硬化処理に関する一考察

抄録

It has not been clearly interpreted yet that the hardness and the abrasion resistance of anodic oxide films are increased by the secondary hardening treatment. In this paper, therefore, the structure changes of anodic oxide films caused by the secondary hardening treatment were investigated by X-ray diffraction method. The effect of pH values of treating solutions on the hardness of anodic oxide films was also investigated. As a result of the hardening treatment crystalline alumina was detected in the films, although the crystal does not seem to contribute to the increase of the hardness. Other oxides, ZnO and NiO, were observed in the anodic oxide films sealed with solutions which contain zinc acetate and nickel acetate. Increase of the abrasion resistance of the anodic oxide films thus sealed might be explained in terms of lubricating properties of the oxides. The hardness of anodic oxide films, on the other hand, was found to be remarkably increased as well by the chemical treatment using allkalline solutions and by the successive heat-treatment.