在以原子为中心的立方金属中脱位滑动的激活,来自原子学模拟
Arnaud Allera1,2,3,4, Thomas D Swinburne5,6, Alexandra M Goryaeva7
1ASNR/PSN-RES/SEMIA/LSMA Centre d'études de Cadarache, F-13115, Saint Paul-lez-Durance, France. arnaud.allera@asnr.fr.
Nature communications
|September 24, 2025
概括
金属中的激活常常被简化. 这项研究发现,它在脱位滑动过程中保持不变,改进了产量应力模型,并挑战了经典潜力模拟.
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
- 固态物理 固态物理
背景情况:
- 脱位滑动控制金属的强度,但它的激活度通常过于简单化.
- 现有的模型使用恒定或迈耶-内尔德尔定律,这是近似的.
研究的目的:
- 直接计算螺杆位移上曲对核的激活吉布斯能量.
- 研究铁和中激活的温度和应力依赖性.
- 开发一个更准确的模型来预测金属产量压力.
主要方法:
- 开发了机器学习的原子间潜力,在密度函数理论数据上训练铁和.
- 计算激活Gibbs能量用于螺杆位移上的扭曲对核化.
- 用计算激活来参数化一个热激活的产量压力模型.
主要成果:
- 发现脱位滑行体的激活度在温度和应力之间基本是恒定的.
- 位移显示Peierls山谷之间的波过渡.
- 开发的产量应力模型准确地复制了铁和的实验数据.
结论:
- 恒定激活的假设被验证为BCC金属中曲对核化.
- 经典潜力可能会在材料建模中高估效应.
- 准确的激活值计算对于可靠的产量压力预测至关重要.
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