Embedded-atom study of low-energy equilibrium triple junction structures and energies
Embedded-atom study of low-energy equilibrium triple junction structures and energies
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DOI：
10.1016/j.actamat.2016.02.058
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发表时间：
2016-05-01
期刊：
影响因子：
9.4
通讯作者：
Schmitz, G.
中科院分区：
文献类型：
--
作者：
Eich, S. M.;Schmitz, G.
我们提出了多晶材料中三重结（TJs）的结构和缺陷能的原子研究。提出了一种计算分离TJs多余能量的新概念，并将其应用于铁三晶的分子动力学研究。块状TJs（合并三个晶界）和表面TJs（合并一个晶界和两个晶界）的线能很低。它们的绝对值仅为10(-10)Jm（-1）。值得注意的是，在所有被研究的构型中，体TJ能量被确定为负值，其平均值为-2.8 x 10(-10) Jm（-1）。这些定量结果与各种实验尝试相反，但它们完全符合简单的几何估计和断键模型，这促使对报告的测量结果进行重新解释。(C) 2016材料学报Elsevier Ltd.出版。版权所有。
We present an atomistic study of the structures and defect energies of triple junctions (TJs) in polycrystalline materials. A new concept to calculate the excess energy of isolated TJs is proposed and applied to a molecular dynamics (MD) study of iron tricrystals. Line energies of bulk TJs (merging three grain boundaries (GBs)) and surface TJs (merging one grain boundary and two surfaces) are found to be very low. In absolute value they amont to only a few 10(-10) Jm(-1). Remarkably, defined as a correct excess energy relative to the GBs, the bulk TJ energy is determined to be negative in all studied configurations with an average value of -2.8 x 10(-10) Jm(-1). These quantitative results are in contrast to various experimental attempts, but they fully agree with simple geometric estimates and broken-bond models, which prompts a re-interpretation of reported measurements. (C) 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.