Devincre B, Hoc T, Kubin L
Laboratoire d'Etude des Microstructures, Unité Mixte de Recherche (UMR) 104 CNRS, CNRS-Office National d'Etudes et de Recherches Aérospatiales (ONERA), 20 Avenue de la Division Leclerc, BP 72, 92322 Chatillon Cedex, France.
Science. 2008 Jun 27;320(5884):1745-8. doi: 10.1126/science.1156101.
Predicting the strain hardening properties of crystals constitutes a long-standing challenge for dislocation theory. The main difficulty resides in the integration of dislocation processes through a wide range of time and length scales, up to macroscopic dimensions. In the present multiscale approach, dislocation dynamics simulations are used to establish a dislocation-based continuum model incorporating discrete and intermittent aspects of plastic flow. This is performed through the modeling of a key quantity, the mean free path of dislocations. The model is then integrated at the scale of bulk crystals, which allows for the detailed reproduction of the complex deformation curves of face-centered cubic crystals. Because of its predictive ability, the proposed framework has a large potential for further applications.
预测晶体的应变硬化特性是位错理论长期面临的挑战。主要困难在于如何在从微观到宏观的广泛时间和长度尺度上整合位错过程。在当前的多尺度方法中，位错动力学模拟被用于建立一个基于位错的连续介质模型，该模型包含了塑性流动的离散和间歇性特征。这是通过对一个关键量——位错平均自由程进行建模来实现的。然后，该模型在体晶体尺度上进行整合，从而能够详细再现面心立方晶体复杂的变形曲线。由于其预测能力，所提出的框架具有进一步应用的巨大潜力。
