第一原则研究了Y2O3的表面和内部扩散
Weihao Ye1, Chuan-Hui Zhang1, Liwu Jiang1
1National Center for Materials Service Safety, University of Science and Technology Beijing, Beijing, 102206, China. zhangch@ustb.edu.cn.
Physical chemistry chemical physics : PCCP
|October 20, 2025
概括
氧化物 (Y2O3) 涂层有效地防止合金中的透. 这项研究揭示了表面氧气空缺是扩散到Y2O3的关键,为改善抗性提供了洞察力.
科学领域:
- 材料科学 材料科学 材料科学
- 表面科学是一门学科.
- 气的脆弱性 气的脆弱性
背景情况:
- 氧化物 (Y2O3) 是防止合金中透的关键涂层材料.
- 在暴露下对Y2O3涂层的性能和相互作用机制的研究有限.
研究的目的:
- 研究Y2O3.3.内部的吸附和扩散机制.
- 阐明表面氧空缺在通过Y2O3涂层透中的作用.
主要方法:
- 密度函数理论 (DFT) 的计算用于在Y2O3表面上建模吸附和扩散.
- 表面能量计算确定了最稳定的Y2O3表面终端 (O层).
- 计算出了扩散的迁移能量障碍,考虑了间歇性位置和空缺位置.
主要成果:
- O层终止的Y2O3表面在能量上是有利的.
- 表面的不和氧原子促进了吸附.
- 表面的氧气空隙作为关键的中间点,降低了气扩散到Y2O3散体中的能量屏障.
- 通过八面体和四面体间位点确定了散通路.
- 计算的扩散系数和透度与实验数据非常一致.
结论:
- 表面的氧气空隙显著增强了气扩散到Y2O3.3.
- 了解这些机制为设计更有效的Y2O3涂层提供了理论基础,并提高了抗性.
- 这些发现有助于减轻使用Y2O3保护层的合金中的脆性.
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