论文标题
年轻的模量对DP钢中塑性应变的依赖性：异质性的结果？
Dependency of the Young's modulus to plastic strain in DP steels: a consequence of heterogeneity ?
论文作者
论文摘要
据报道，双阶段（DP）钢的准确回弹预测是一个重大挑战。证明这是由于缺乏对他们的非线性卸载行为的了解，尤其是其卸载模量对塑料prestrain的依赖。开发了所谓的分隔有限元模型。在此模型中，每个元素都被分配了独特的线性弹性J2塑性行为而无需硬化。该模型的特异性在于以下事实：（i）以确定性的方式离散统计分布，并用来将屈服应力分配给称为隔室的结构； （ii）这些隔室通过随机隔室元素映射（CEM）随机与元素相关联。并行模拟多个CEM，以研究模型的固有随机性。该模型面临从文献中提取的实验数据，并证明该模型能够重现明显模量对拉伸曲折的依赖性。还观察到，即使它不是用于识别模型的输入参数的实验数据集的明确输入，也可以预测明显模量的演变。然后推断出硬化的形状和模量对序列的依赖是单个原因的两个表现：DP钢中的异质屈服应力。
The accurate springback prediction of dual phase (DP) steels has been reported as a major challenge. It was demonstrated that this was due to the lack of understanding of their nonlinear unloading behavior and especially the dependency of their unloading moduli on the plastic prestrain. A so-called compartmentalized finite element model was developed. In this model, each element was assigned a unique linear elastic J2 plastic behavior without hardening. The model's specificity lied in the fact that: (i) a statistical distribution was discretized in a deterministic way and used to assign yield stresses to structures called compartments; (ii) those compartments were randomly associated with the elements through a random compartment element mapping (CEM). Multiple CEM were simulated in parallel to investigate the intrinsic randomness of the model. The model was confronted with experimental data extracted from the literature and it was demonstrated that the model was able to reproduce the dependence of the apparent moduli on the tensile prestrain. It was also observed that the evolution of the apparent moduli was predicted even if it was not an explicit input of the experimental dataset used to identify the input parameters of the model. It was then deduced that the shape of the hardening and the dependancy of moduli on the prestrain were two manifestations of a single cause: the heterogeneous yield stress in DP steels.
