Abstract In this paper, an infinitesimal-strain based FFT formulation is extended to account for deformation twinning in hexagonal close-packed (HCP) materials. A model called the Complex Voxel (CV) model is developed that includes twinning as pseudo-slip and accounts for interaction between parent grains and corresponding twin variants by assuming a Taylor-type approximation at the voxel level. The macroscopic deformation behavior of Magnesium alloy AZ31, a representative HCP material, is simulated in three different loading directions. Detailed analysis of twinning dominated deformation reveals that: (a) Global Schmid factors indicate twin variant selection and the rate of twin growth; (b) Basal slip is the dominant active slip system during the twin nucleation and twin growth stages; (c) A comparison of numerical results of the present study with the published experimental and numerical studies indicate that the evolution of local stress states in parent grains and corresponding twin variants depend on their orientation with respect to the loading direction and/or the neighbouring grains. Further, the need of immediate experimental evidence to assist assumptions made during modelling deformation twinning is discussed.

中文翻译：

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基于晶体塑性 FFT 的 HCP 材料变形孪晶、各向异性和微观力学研究：在 AZ31 合金中的应用

摘要 在本文中，扩展了基于无穷小应​​变的 FFT 公式以解决六边形密堆积 (HCP) 材料中的形变孪晶问题。开发了一种称为复合体素 (CV) 模型的模型，该模型包括作为伪滑移的孪晶，并通过假设体素水平的泰勒型近似来解释母粒和相应孪晶变体之间的相互作用。镁合金 AZ31（一种代表性的 HCP 材料）的宏观变形行为在三个不同的加载方向上进行了模拟。孪生主导变形的详细分析表明：（a）全局施密德因子表明孪生变体选择和孪生生长速率；(b) 在孪生成核和孪生生长阶段，基底滑移是主要的主动滑移系统；(c) 本研究的数值结果与已发表的实验和数值研究的比较表明，母体晶粒和相应孪晶变体中局部应力状态的演变取决于它们相对于加载方向和/或相邻晶粒的取向. 此外，还讨论了需要立即的实验证据来帮助在模拟变形孪生过程中做出的假设。