论文标题
关于晶界迁移率的温度依赖性
On the Temperature Dependence of Grain Boundary Mobility
论文作者
论文摘要
晶界（GB）的迁移率将GB速度与热力学驱动力相关联，这是我们对多晶中微观结构演化的理解至关重要的。最近的分子动力学（MD）和实验研究表明，GB迁移率的温度依赖性比通常认为的多种多样。 GB迁移率可能随着温度升高而增加，减小，保持恒定或显示多个峰。我们基于GB内线缺陷（断开连接）的形成和迁移而提出了一个用于GB迁移的机械模型。我们在动力学的蒙特卡洛和统计力学框架中实施了该模型。结果捕获了所有这些观察到的温度依赖性，并被证明是彼此定量一致的，并且在一组特定的晶界中，GB迁移的直接MD模拟。 GB迁移率对断开模式和温度的依赖性的检查提供了有关GBS在多晶材料中迁移的新见解。
The grain boundary (GB) mobility relates GB velocity to the thermodynamic driving forces and is central to our understanding of microstructure evolution in polycrystals. Recent molecular dynamics (MD) and experimental studies have shown that the temperature-dependence of the GB mobility is much more varied than is commonly thought. GB mobility may increase, decrease, remain constant or show multiple peaks with increasing temperature. We propose a mechanistic model for GB migration, based on the formation and migration of line defects (disconnection) within the GB. We implement this model in a kinetic Monte Carlo and statistical mechanics framework; the results capture all of these observed temperature dependencies and are shown to be in quantitative agreement with each other and direct MD simulations of GB migration for a set of specific grain boundaries. Examination of the dependence of GB mobility on disconnection mode and temperature provides new insight into how GBs migrate in polycrystalline materials.
