Origin of differences in the excess volume of copper and nickel grain boundaries
Origin of differences in the excess volume of copper and nickel grain boundaries
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DOI：
10.1016/j.actamat.2016.02.040
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发表时间：
2016-05
期刊：
影响因子：
9.4
通讯作者：
Jonathan Bean;K. McKenna
中科院分区：
文献类型：
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作者：
Jonathan Bean;K. McKenna
与晶界相关的过量体积是驱动缺陷偏析和扩散的主要因素之一，缺陷偏析和扩散控制着许多多晶材料的电子、机械和化学性能。面心立方金属Cu和Ni的晶界过剩体积的实验测量显示出超过40%的差异。 Cu 和 Ni 之间的晶格常数差异仅为 3%，因此这种实质性差异目前缺乏解释。在本文中，我们采用高通量计算方法来确定铜和镍中大量倾斜晶界的原子结构、形成能和过剩体积。通过考虑 400 个不同的晶界取向，我们确认理论上两种材料的过量体积之间存在系统差异，并且我们提供了对该效应起源的原子洞察。
The excess volume associated with grain boundaries is one of the primary factors driving defect segregation and diffusion which controls the electronic, mechanical and chemical properties of many polycrystalline materials. Experimental measurements of the grain boundary excess volume of fcc metals Cu and Ni have shown a difference of over 40%. The difference in lattice constant between Cu and Ni is only 3%, therefore this substantial difference is currently lacking explanation. In this article we employ a high throughput computational approach to determine the atomic structure, formation energy and excess volume of a large number of tilt grain boundaries in Cu and Ni. By considering 400 distinct grain boundary orientations we confirm that theoretically there is a systematic difference between the excess volumes in the two materials and we provide atomistic insight into the origin of the effect.