青春作为CrCoNi中等合金中平面缺陷的起源
Yang Yang1,2, Sheng Yin3, Qin Yu3
1National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, USA. yangyang@alum.mit.edu.
Nature communications
|February 16, 2024
概括
在高合金 (HEAs) 中,短距离秩序 (SRO) 破坏会使材料再生,增强柔性. 这项研究直接观察了循环加载期间的SRO复原,揭示了它与特殊机械性能的联系.
科学领域:
- 材料科学 材料科学 材料科学
- 金工业是金工业的一个方面.
- 固体力学 固体力学是什么
背景情况:
- 高和中合金 (HEAs/MEAs) 具有显著的机械性能.
- 潜在的机制,特别是短程订单 (SRO) 的作用,仍然不清楚.
研究的目的:
- 直接观察和验证HEAs/MEAs预测的复苏情况.
- 阐明SRO,变形机制和卓越的机械性能之间的联系.
主要方法:
- 在现场提供与4D-STEM集成的机械测试.
- 在室温下单晶CrCoNi的循环机械负荷.
- 分子动力学 (MD) 模拟.分子动力学 (MD) 模拟.
主要成果:
- 在循环加载过程中直接观察SRO再生.
- 堆叠断层和双边界显示可逆到不可逆的过渡,表明堆叠断层能量减少.
- MD模拟证实SRO崩触发了这些变化.
结论:
- 当地SRO分解是HEAs/MEAs复原的关键机制.
- 复原通过局部化变形来增强柔性和耐损性.
- 这为HEA/MEA的特殊性质提供了机械的理解.
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