短距离顺序及其对CrCoNi中合金的影响
Ruopeng Zhang1,2, Shiteng Zhao1,2, Jun Ding3
1Department of Materials Science and Engineering, University of California, Berkeley, CA, USA.
Nature
|May 21, 2020
概括
在CrCoNi中等合金中实验观察到短程顺序. 这种原子排列增强了硬度和堆叠缺陷能量等机械特性.
科学领域:
- 材料科学
- 金属工程
- 固态物理
背景情况:
- 传统的合金具有随机原子分布或二次相.
- 多重主元素合金 (MPEA) 是具有增强机械性能的单相固体溶液.
- 中等合金 (MEAs) 和高合金 (HEAs) 是MPEAs的一种类型.
研究的目的:
- 在CrCoNi中等合金中实验研究短距离秩序的存在和影响.
- 探索短距离秩序与机械性能之间的关系.
主要方法:
- 使用能量过传输电子显微镜 (EF-TEM) 来观察结构特征.
- 分析的重点是CrCoNi中合金系统.
主要成果:
- 在CrCoNi MEA中观察到可归因于短程订单的结构特征.
- 增加短距离顺序与更高的堆叠故障能量相关.
- 这种更高的秩序导致了材料的硬度增加.
结论:
- 短距离订单存在,并且可以在MEA中实验验证.
- 通过热机械加工量身定制, 提供了一种调整合金性能的新方法.
- 这一发现为设计具有卓越机械性能的先进MEA和HEA开辟了新的途径.
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