纳米沉中的化学短距离排序调节平面断层以增强机械性能
Qing Zhang1,2, Yixuan Hu1, Tao Yang3,4,5
1State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240, P. R. China.
Nano letters
|April 25, 2025
概括
这项研究引入了纳米沉物中的原子级化学异质性,以增强金属材料的强度和可塑性. 沉物中的短距离排序 (SRO) 通过改变缺陷能量格局来改善机械性能.
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.
- 计算材料科学科学 计算材料科学
背景情况:
- 纳米沉物通过阻碍脱位运动来增强金属材料的强度.
- 然而,纳米沉材料往往会导致材料柔性降低.
- 控制沉物微观结构是平衡强度和延展性的关键.
研究的目的:
- 开发一种新的策略,以提高纳米沉物增强合金的可塑性.
- 研究纳米沉物中原子级化学异质性的作用.
- 探索L12排序沉物中短距离排序 (SRO) 的形成和影响.
主要方法:
- 在L12排序的Co40Ni30Cr20Al5Ti4Ta1沉中实验观察和确认明显的短距离排序 (SRO).
- 密度函数理论 (DFT) 计算以阐明SRO的形成机制.
- 分析SRO对平面缺陷能量景观和失位相互作用的影响.
主要成果:
- 首次观察并确认在多主元素合金中的L12级沉物中显著的SRO.
- SRO重新塑造平面缺陷的能量格局,从而提高了强度和工作硬化能力.
- SRO增加了沉切割的临界切割应力,并减少了堆叠断层形成能量,促进了核化.
结论:
- 原子级化学异质性,特别是SRO,是增强强度和可塑性的可行策略.
- 这项工作建立了一种新的方法,用于在有序结构中定制原子排列.
- 开拓者通过控制沉物的异质性来推进高性能材料设计.
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