Kinetic mechanism of anodic oxidation of tantalum in nitrate melts

来源期刊：中国有色金属学报(英文版)2000年第5期

论文作者：张德元 陆德平 李放 蔡莉 许兰萍 林勤

文章页码：695 - 698

Key words：kinetics; anodic oxidation; tantalum

Abstract: The data of anodic oxidation of tantalum in high temperature nitrate melts were regressed according to 41 kinds of probable kinetic mechanism. The results show that the process follows the parabolic lawα²=kt, which means that the process of anodic oxidation of tantalum is limited by the movement of positive vacancies of tantalum ions. The voltage has an effect on the rate constant in prior period, which implies that the electromigration exists at the beginning of film growth. The breakdown of films exists in whole process. The films obtained are composed of orthorhombic β-Ta₂O₅ and TaO_y.