{"title":"First-principles study on the diffusion behavior of Cs and I in Cr coating","authors":"Shu-Ying Lin, Xiao-Jing Li, Lin-Bing Jiang, Xi-Jun Wu, Hui-Qin Yin, Yu Ma, Wen-Guan Liu","doi":"10.1007/s41365-024-01460-y","DOIUrl":null,"url":null,"abstract":"<p>Cs and I can migrate through fuel-cladding interfaces and accelerate the cladding corrosion process induced by the fuel-cladding chemical interaction. Cr coating has emerged as an important candidate for mitigating this chemical interaction. In this study, first-principles calculations were employed to investigate the diffusion behavior of Cs and I in the Cr bulk and grain boundaries to reveal the microscopic interaction mitigation mechanisms at the fuel-cladding interface. The interaction between these two fission products and the Cr coating were studied systematically, and the Cs and I temperature-dependent diffusion coefficients in Cr were obtained using Bocquet’s oversized solute-atom model and Le Claire’s nine-frequency model, respectively. The results showed that the Cs and I migration barriers were significantly lower than that of Cr, and the Cs and I diffusion coefficients were more than three orders of magnitude larger than the Cr self-diffusion coefficient within the temperature range of Generation-IV fast reactors (below 1000 K), demonstrating the strong penetration ability of Cs and I. Furthermore, Cs and I are more likely to diffuse along the grain boundary because of the generally low migration barriers, indicating that the grain boundary serves as a fast diffusion channel for Cs and I.</p>","PeriodicalId":19177,"journal":{"name":"Nuclear Science and Techniques","volume":"41 1","pages":""},"PeriodicalIF":3.6000,"publicationDate":"2024-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Nuclear Science and Techniques","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1007/s41365-024-01460-y","RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"NUCLEAR SCIENCE & TECHNOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Cs and I can migrate through fuel-cladding interfaces and accelerate the cladding corrosion process induced by the fuel-cladding chemical interaction. Cr coating has emerged as an important candidate for mitigating this chemical interaction. In this study, first-principles calculations were employed to investigate the diffusion behavior of Cs and I in the Cr bulk and grain boundaries to reveal the microscopic interaction mitigation mechanisms at the fuel-cladding interface. The interaction between these two fission products and the Cr coating were studied systematically, and the Cs and I temperature-dependent diffusion coefficients in Cr were obtained using Bocquet’s oversized solute-atom model and Le Claire’s nine-frequency model, respectively. The results showed that the Cs and I migration barriers were significantly lower than that of Cr, and the Cs and I diffusion coefficients were more than three orders of magnitude larger than the Cr self-diffusion coefficient within the temperature range of Generation-IV fast reactors (below 1000 K), demonstrating the strong penetration ability of Cs and I. Furthermore, Cs and I are more likely to diffuse along the grain boundary because of the generally low migration barriers, indicating that the grain boundary serves as a fast diffusion channel for Cs and I.
铯和碘可以通过燃料-包壳界面迁移,并加速燃料-包壳化学作用引起的包壳腐蚀过程。铬涂层已成为减轻这种化学作用的重要候选材料。本研究采用第一性原理计算来研究铯和碘在铬的块体和晶界中的扩散行为,以揭示燃料-包壳界面上的微观相互作用缓解机制。系统研究了这两种裂变产物与铬包层之间的相互作用,并利用 Bocquet 的超大溶质原子模型和 Le Claire 的九频模型分别求出了 Cs 和 I 在铬中随温度变化的扩散系数。结果表明,在第四代快堆温度范围内(1000 K 以下),铯和碘的迁移障碍明显低于铬,铯和碘的扩散系数比铬的自扩散系数大三个数量级以上,这表明铯和碘具有很强的渗透能力。此外,由于铯和碘的迁移障碍普遍较低,它们更容易沿着晶界扩散,这表明晶界是铯和碘的快速扩散通道。
期刊介绍:
Nuclear Science and Techniques (NST) reports scientific findings, technical advances and important results in the fields of nuclear science and techniques. The aim of this periodical is to stimulate cross-fertilization of knowledge among scientists and engineers working in the fields of nuclear research.
Scope covers the following subjects:
• Synchrotron radiation applications, beamline technology;
• Accelerator, ray technology and applications;
• Nuclear chemistry, radiochemistry, radiopharmaceuticals, nuclear medicine;
• Nuclear electronics and instrumentation;
• Nuclear physics and interdisciplinary research;
• Nuclear energy science and engineering.