Heterogeneous deformation in ductile FCC single crystals in biaxial stretching: the influence of slip system interactions
Heterogeneous deformation in ductile FCC single crystals in biaxial stretching: the influence of slip system interactions
复制标题
DOI：
10.1016/j.jmps.2015.05.020
复制
发表时间：
2015-10-01
影响因子：
5.3
通讯作者：
Madec, R.
中科院分区：
文献类型：
--
作者：
Dequiedt, J. L.;Denoual, C.;Madec, R.
采用数值模拟和解析相结合的方法研究了FCC单晶塑性变形的非均匀性。本构行为基于广义存储恢复模型，并考虑了先前通过位错动力学模拟获得的滑移系统之间的相互作用。在双轴拉伸中，模拟显示了大量滑移系统的激活及其在相互排斥区内的局部化。结果表明，在变形初期形成了片层型显微组织。这些数值结果与线性稳定性分析相辅相成，表明非均质变形模式是由单晶的不稳定模式引发的。此外，相互作用矩阵起着关键作用，因为发现分区源于滑移系统的相互作用。划分是由最强的相互作用驱动的，在大多数情况下是共线相互作用。与简单剪切试验研究的比较提供了关于如何检查某些相互作用各自强度的有用信息。在这种情况下不涉及共线相互作用，但其影响可以通过在不同取向的晶体上重现实验来验证。(C) 2015 Elsevier Ltd.版权所有。
The heterogeneity of deformation in ductile FCC single crystals is investigated by both numerical simulations and an analytic approach. The constitutive behaviour is based on a generalized storage recovery model and takes into account the interactions between slip systems previously obtained by dislocation dynamics simulations. In biaxial stretching, the simulations show the activation of a large number of slip systems and their localization in mutually excluding zones. As a result, a microstructure of lamellar type is formed in the early stages of the deformation. These numerical results are complemented by a linear stability analysis showing that the heterogeneous deformation pattern is triggered by instability modes of the single crystal. Furthermore, the interaction matrix is playing a key role as the partition is found to originate from slip system interactions. The partition is driven by the strongest interaction, which is in most cases the collinear interaction. A comparison with an experimental study in simple shear yields useful information about how to check the respective strength of some interactions. The collinear interaction is not involved in that case, but its effect can be verified by reproducing the experiment on a crystal with a different orientation. (C) 2015 Elsevier Ltd. All rights reserved.