On the structure of tilt grain boundaries in cubic metals I. Symmetrical tilt boundaries
On the structure of tilt grain boundaries in cubic metals I. Symmetrical tilt boundaries
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DOI：
10.1098/rsta.1983.0020
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发表时间：
1983-03
期刊：
影响因子：
--
通讯作者：
A. Sutton;V. Vítek
中科院分区：
文献类型：
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作者：
A. Sutton;V. Vítek
f.c.c.中倾斜晶界结构的原子学研究。金属已经制成。本研究的主要目的是了解长周期（“一般”）倾斜边界的结构。考虑了符合点密度的倒数，其中，符合点密度的倒数为λ < 491。这项工作分三个部分。本文报道了铝和铜中对称倾斜晶界的三个系列的原子学研究。其主要目的之一是确定是否存在的应力场的局部晶界位错偏离任何短周期边界取向远离边界。在这些研究结果的基础上，介绍了一种新的晶界结构分类。某些边界被发现是其他边界附近的取向差范围内的基本结构元素。由一种基本结构要素的连续序列组成的边界称为有利的;所有其他边界称为非有利的。发现有利的晶界并不总是与最低可能的ε值相关联，并且在具有相同晶体结构的所有金属中，相同的晶界不一定是有利的。利用对相互作用计算原子水平的应力张量，显示了界面的静水应力场。在所有情况下，被认为是不同的，本地化的固有晶界位错的应力场被发现在非有利的边界。引入了有取向差的边界结构连续性的概念。结果表明，边界结构的连续性要求在所有的取向差上都有唯一的边界结构。利用这一概念，它演示了如何可以预测的原子结构和应力场的任何非有利的边界之间的两个已知的，连续的有利边界。它也被发现，一个孤立的不连续变化的边界结构之间的两个连续的有利边界可能存在，这取决于它们的平移状态。f.c.c.中倾斜边界的一些早期原子论研究。和BC。根据这项工作重新解释了金属。
An atomistic study of tilt grain boundary structures in f.c.c. metals has been made. The principal aim of this study is to understand the structure of long-period (‘general’) tilt boundaries. Boundaries for which Σ< 491 were considered, where Σ is the reciprocal density of coincidence sites. The work is presented in three parts. In this paper three series of atomistic studies of symmetrical tilt boundaries in aluminium and copper are reported. One of the main objectives is to determine whether the stress fields of localized grain boundary dislocations exist in boundaries deviated far from any short-period boundary orientations. On the basis of the results of these studies, a new structural classification of grain boundaries is introduced. Certain boundaries are found to be the fundamental structural elements of other boundaries nearby in the misorientation range. Boundaries that consist of contiguous sequences of one type of fundamental structural elements are called favoured; all other boundaries are called non-favoured. Itis found that favoured boundaries are not always associated with the lowest possible values of Σ and that the same boundaries are not necessarily favoured in all metals with the same crystal structure. With use of the pair interactions to calculate the atomic level stress tensor, the hydrostatic stress fields of the boundaries are displayed. In all cases considered the stress fields of distinct, localized intrinsic grain boundary dislocations were found in non-favoured boundaries. The concept of continuity of boundary structure with misorientation is introduced. It is shown that continuity of boundary structure requires unique boundary structures at all misorientations. With use of this concept it is demonstrated how one can predict the atomic structure and stress field of any non-favoured boundary between two known, successive favoured boundaries. It is also found that an isolated discontinuous change in boundary structure between two successive favoured boundaries may exist, depending on their translation states. Some earlier atomistic studies of tilt boundaries in f.c.c. and b.c.c. metals are reinterpreted in the light of this work.