Grain boundary (GB) migration and Zener pinning, i.e. retardment of migrating GBs by second-phase particles, in a nanocrystalline Cu–Ag alloy have been investigated via molecular dynamics simulation. Among 86 GBs of different rotation axes and misorientation angles, about half of the GBs either did not move for an obvious distance within limited simulation time or underwent unsteady migration, and the other GBs exhibited steady migration. For the motionless and unsteady-migration GBs, boundary faceting was frequently observed. In particular, as found in experiments, all low angle GBs and several high angle GBs became faceted. For the steady-migration GBs, rotation-axis and misorientation dependences of GB energy, GB mobility and particle pinning effects have been systematically revealed. It is found that both the energy and mobility of low angle GBs were generally lower than those of high angle GBs, GBs of distinct rotation axes differed in mobility by as large as three orders o...

中文翻译：

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纳米晶Cu-Ag合金的晶界迁移和齐纳钉扎

通过分子动力学模拟研究了纳米晶Cu-Ag合金中的晶界（GB）迁移和齐纳钉扎，即第二相粒子对GBs的迁移阻滞。在86 GB的不同旋转轴和方向错误的角度中，大约一半的GB在有限的模拟时间内没有移动明显的距离，或者经历了不稳定的迁移，而其他GB则表现出稳定的迁移。对于静止的和不稳定的迁移GB，经常观察到边界刻面。特别是，如在实验中发现的，所有低角度GB和几个高角度GB都变成了小平面。对于稳态迁移的GBs，系统地揭示了GB能量的旋转轴和取向错误，GB迁移率和粒子钉扎效应。