In-situ EBSD study of the active slip systems and lattice rotation behavior of surface grains in aluminum alloy during tensile deformation
In-situ EBSD study of the active slip systems and lattice rotation behavior of surface grains in aluminum alloy during tensile deformation
复制标题
铝合金拉伸变形过程中主动滑移系统和表面晶粒晶格旋转行为的原位 EBSD 研究
DOI：
10.1016/j.msea.2013.05.046
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发表时间：
2013-09-15
期刊：
影响因子：
6.4
通讯作者：
Han, X. D.
中科院分区：
文献类型：
--
作者：
Chen, P.;Mao, S. C.;Han, X. D.
本文报告了通过电子背散射衍射方法对多晶铝合金表面晶粒的塑性变形行为，特别是主动滑移系统和晶格旋转进行的原位研究。实验分析在1μm的空间分辨率下进行，因此可以在亚晶粒水平上进行详细分析，从而能够阐明文献中不常见的变形过程的精细细节。研究发现，在拉伸变形过程中，随着应变的增加，晶粒逐渐旋转。晶格旋转，无论是旋转路径还是旋转速率，在晶粒之间和单个晶粒内部都高度不均匀，导致亚晶粒的形成。旋转行为可以通过激活具有最大和第二大施密德因子的滑移系统来充分描述。正如晶体塑性理论所预测的那样，表面晶粒中独立滑移系统的数量远少于内部晶粒中的数量。对于不同的变形阶段，晶格旋转速率在晶粒和子区域之间也是不均匀的。旋转速率的差异提供了另一种调节塑性应变和产生亚晶粒的机制。这些发现对于薄板材料的机械加工或微型部件的变形行为非常重要，其中大多数晶粒位于表面。 (C) 2013 Elsevier B.V. 保留所有权利。
This paper reports an in-situ study of the plastic deformation behavior of surface grains in a polycrystalline aluminum alloy, in particular the active slip systems and lattice rotation, by means of the electron backscattered diffraction method. The experimental analysis is conducted at a spatial resolution of 1 mu m, thus allowing detailed analysis at subgrain levels, enabling elucidation of fine details of the deformation process that are not commonly seen in the literature. It is found that the grains rotate gradually with increasing strain during tensile deformation. The lattice rotation, in terms of both rotation path and rotation rate, is highly inhomogeneous both among the grains and within individual grains, leading to the formation of subgrains. The rotation behavior can be adequately described by the activation of slip systems with the maximum and second maximum Schmid factors. The number of independent slip systems in surface grains is much fewer than that in interior grains, as predicted by crystal plasticity theories. The lattice rotation rate is also heterogeneous among grains and subregions and for different deformation stages. The differences in rotation rate provide another mechanism for the accommodation of plastic strains and for the creation of subgrains. These findings are of importance for the mechanical processing of thin sheet materials or the deformation behavior of miniature components, where the majority of grains are on the surfaces. (C) 2013 Elsevier B.V. All rights reserved.