Effects of oxygen concentration and irradiation defects on the oxidation corrosion of body-centered-cubic iron surfaces: A first-principles study

作者：Zhiqiang Ye, Yawei Lei, Jingdan Zhang, Yange Zhang, Xiangyan Li, Yichun Xu, Xuebang Wu, C. S. Liu, Ting Hao, Zhiguang Wang · 发表于：Chinese Physics B · 年份：2022 · DOI：10.1088/1674-1056/ac633c · 被引用次数：11 · 研究领域：High-Temperature Coating Behaviors、Nuclear Materials and Properties、Fusion materials and technologies

Oxidation corrosion of steels usually occurs in contact with the oxygen-contained environment, which is accelerated by high oxygen concentration and irradiation. The oxidation mechanism of steels is investigated by the adsorption/solution of oxygen atoms on/under body-centered-cubic (bcc) iron surfaces, and diffusion of oxygen atoms on the surface and in the near-surface region. Energetic results indicate that oxygen atoms prefer to adsorb at hollow and long-bridge positions on the Fe(100) and (110) surfaces, respectively. As the coverage of oxygen atoms increases, oxygen atoms would repel each other and gradually dissolve in the near-surface and bulk region. As vacancies exist, oxygen atoms are attracted by vacancies, especially in the near-surface and bulk region. Dynamic results indicate that the diffusion of O atoms on surfaces is easier than that into near-surface, which is affected by oxygen coverage and vacancies. Moreover, the effects of oxygen concentration and irradiation on oxygen density in the near-surface and bulk region are estimated by the McLean’s model with a simple hypothesis.