应变速率对CuZr金属玻璃机械变形行为的影响
Beibei Fan1, Maozhi Li1,2
1Beijing Key Laboratory of Opto-Electronic Functional Materials & Micro-Nano Devices, Department of Physics, Renmin University of China, Beijing 100872, China.
Materials (Basel, Switzerland)
|June 19, 2024
概括
增加铜-金属玻璃的拉伸率,通过促进更均的变形,提高了产量强度. 这项分子动力学研究揭示了应变速率在变形过程中显著影响机械反应和原子结构演变.
科学领域:
- 材料科学 材料科学 材料科学
- 计算材料科学科学 计算材料科学
- 机械工程 机械工程
背景情况:
- 金属玻璃表现出独特的机械性能,受变形条件的影响.
- 了解拉伸率和变形行为之间的关系对于它们的应用至关重要.
- 经典分子动力学模拟提供了一个强大的工具,以探测纳米尺度变形机制.
研究的目的:
- 为了研究高拉伸速率 (10^7到10^9 /s) 对Cu64Zr36金属玻璃变形行为的影响.
- 阐明控制应变速率依赖的可塑性和结构演变的基本机制.
- 为了将原子结构的变化与宏观的机械反应相关联.
主要方法:
- 经典的分子动力学模拟被用来进行拉力测试.
- 模拟是在三种不同的应变速率进行的: 10^7/s, 10^8/s和 10^9/s.
- 分析的重点是产量强度,原子结构演变,·米塞斯菌株和菌株局部化.
主要成果:
- 收益强度随着延展率的增加而显著增加.
- 较高的拉伸率导致更均的变形和减少拉伸局部化.
- 原子结构的进化显示了跨菌株速率的差异,结构特征以更高的速度消失,促进同质性.
结论:
- 应变率是控制金属玻璃变形行为和机械性能的关键因素.
- 增加的拉伸率通过减少变形异质性和促进更均的原子重新排列来提高产量强度.
- 这些发现为金属玻璃的变形机制提供了宝贵的见解,指导材料设计和应用.
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