在酸混合酸中M5层的溶解行为
Ying Chen1, Yandong Sun1, Yang Bai1
1China Institute of Atomic Energy, Beijing 102413, China.
Materials (Basel, Switzerland)
|December 17, 2024
概括
这项研究表明,将酸 (HNO3) 添加到酸 (HF) 中显著减缓了M5层溶解. 酸还可以防止腐蚀,改善燃料再加工和覆盖的均性.
科学领域:
- 核材料科学 科学 核材料科学
- 腐蚀工程 腐蚀工程
- 化学回收加工 化学回收加工
背景情况:
- 由于其耐腐蚀性,M5外是核燃料中的关键材料.
- 了解M5层溶解对于废燃料管理和再加工至关重要.
研究的目的:
- 为了研究M5层在酸酸 (HF-HNO3) 混合物中的溶解行为.
- 为了确定不同的HF和HNO3度对溶解速率和表面特征的影响.
主要方法:
- 在HF-HNO混合酸中对M5层进行实验性溶解试验.
- 测量表面的粗度. 测量表面的粗度.
- 表面结构分析以阐明溶解机制.
主要成果:
- 如果HF度超过0.5mol/L,HNO3的添加会显著降低M5层溶解率.
- HNO3有效地抑制了HF诱导的腐蚀坑,在1:5 HF:HNO3比率下达到0.812μm的表面粗度.
- 表面分析显示,Nb沉氧化为Nb2O5,M5矩阵氧化为ZrO2,形成一个保护性被动化层.
结论:
- 在HF-HNO混合酸中在M5外上形成ZrO2被动化层抑制了进一步的溶解.
- 酸在控制M5层溶解速度和提高表面均性方面发挥着至关重要的作用,这对核燃料再加工有利.
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