铜在冲击压缩下发生的热力学路径决定的微观结构演变
Weidong Ling1, Bo Chen1, Zengxiu Zhao1
1Department of Physics, National University of Defense Technology, Changsha, Hunan 410073, People's Republic of China.
概括
铜中的冲击波显示方向依赖. 模拟显示,冲击的冲击使得
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 冲击物理 冲击物理
背景情况:
- 铜中的冲击诱导的结构变化显示方向依赖性和异构性.
- 基于晶体学方向的物质对冲击反应的机制尚未完全理解.
研究的目的:
- 通过大规模模拟,研究单晶铜中冲击波传播和结构转变动态.
- 阐明晶体定向和热力学路径在冲击诱导的相位过渡中的作用.
主要方法:
- 大规模的非平衡分子动力学 (NEMD) 模拟.
- 对单晶铜在不同方向上的冲击波传播和结构演变的分析.
主要成果:
- 不同类型的结构进化是由热力学路径决定的.
- 沿着[100]方向的冲击会引起快速的温度升,导致固体-固体相位过渡.
- 沿着[111]方向的冲击导致由于热力学超冷却导致的转移稳定的液态,在超冷却线以下仍然观察到化.
结论:
- 热力学途径在冲击下批判性地决定了异性质结构演变.
- 不同向性,热力学路径和固态失调对于解释冲击诱导的相位过渡至关重要.
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