Comparison of full field predictions of crystal plasticity simulations using the Voce and the dislocation density based hardening laws
Comparison of full field predictions of crystal plasticity simulations using the Voce and the dislocation density based hardening laws
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DOI：
10.1016/j.ijplas.2021.103099
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发表时间：
2021-09
影响因子：
9.8
通讯作者：
C. Patil;Supriyo Chakraborty;S. Niezgoda
中科院分区：
文献类型：
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作者：
C. Patil;Supriyo Chakraborty;S. Niezgoda
晶体塑性建模和模拟是理解多晶材料在不同载荷条件下变形的重要预测工具。这些模拟的有效性和准确性取决于本构关系的选择。塑性变形本构关系的主要组成部分之一是硬化定律。因此，本研究的重点是理解的现象学Voce硬化法和位错密度为基础的硬化法晶体塑性模拟全场预测的效果。采用基于三维快速傅立叶变换的弹粘塑性（EVP-FFT）细观力学求解器对铜的拉伸变形进行了晶体塑性模拟。模拟结果表明，局部应力分布强烈依赖于硬化规律。平均纹理特征预测的法律没有显着变化。然而，空间取向演化（微观织构）随应变的增加而变化。对于Voce定律，由门槛应力计算的位错密度的空间分布比基于位错密度的硬化定律的预测更均匀。最后，我们的研究结果强调，一个简单的位错密度为基础的存储恢复模型是不足以解释的存储能量分布的取向依赖性。因此，仔细选择硬化定律对于预测局部微观力学场非常重要。
Crystal plasticity modeling and simulation is an important predictive tool for understanding the deformation of polycrystalline materials under diverse loading conditions. The validity and accuracy of these simulations depend on the choice of the constitutive law. One of the main components of the constitutive law for plastic deformation is the hardening law. This study, therefore, focuses on understanding the effect of the phenomenological Voce hardening law and the dislocation density based hardening law on full field predictions of crystal plasticity simulations. The crystal plasticity simulations were performed using a three dimensional (3D) fast Fourier transform-based elasto-viscoplastic (EVP-FFT) micromechanical solver for the tensile deformation of copper. Simulation results show that the local distribution of stress strongly depends on the hardening rule. Average texture characteristics predicted by both the laws do not vary significantly. However, spatial orientation evolution (micro-texture) varies with increasing strain. For the Voce law, spatial distribution of the dislocation density calculated from the threshold stress is more homogeneous than the predictions of the dislocation density based hardening law. Finally, our results highlight that a simple dislocation density based storage–recovery model is insufficient to explain the orientation dependence of the stored energy distribution. Hence, careful choice of the hardening law is important for the prediction of localized micromechanical fields.