INTERNAL OXIDATION OF Fe₃Al DURING HIGH TEMPERATURE OXIDATION

来源期刊：中国有色金属学报(英文版)1998年第1期

论文作者：Wang Yonggang He Yedong Zhu Rizhang

文章页码：52 - 55

Key words：Fe₃Al;　oxidation;　internal oxidation;　corrosion

Abstract: The oxidation behavior of Fe₃Al at 1 000℃in air was studied by thermobalance, scanning electron microscope (SEM) and X-ray diffraction (XRD). It was found that the oxidation kinetics approximately follows the parabolic law; the oxide scale consists of Al₂O₃ and a little amount of Fe₂O₃; and there occurs transgranular internal oxidation. Based on the analyses of the oxide scale and the matrix, an internal oxidation model was proposed, which considers the effect of the long-range ordered structure of Fe₃Al on its hightemperature oxidation. The long-range ordered structure reduces the activity of Al in Fe₃Al, thus reducing the diffusion coefficient of Al in the matrix. Consequently, in the oxidation process, the matrix surface will be seriously depleted in Al and then there occurs internal oxidation.