Hierarchical Multiscale Approach for Modeling the Deformation and Failure of Epoxy-Based Polymer Matrix Composites.
Hierarchical Multiscale Approach for Modeling the Deformation and Failure of Epoxy-Based Polymer Matrix Composites.
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用于模拟环氧基聚合物基复合材料变形和失效的分层多尺度方法。
DOI：
10.1021/acs.jpcb.0c07137
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
J. El
中科院分区：
文献类型：
--
作者：
Xiawa Wu;A. Aramoon;J. El
采用粗粒度分子动力学（CG-MD）模拟表征了聚合物基复合材料纤维周围环氧基的分子结构和力学性能。从这些模拟中，通过测量自由体积孔半径分布作为基质-纤维界面位置的函数来量化分子结构。此外，建立了不同交联程度下环氧树脂力学性能与平均自由体积孔半径之间的相关性。然后将这些结果升级为PMC代表体积的有限元模型（FEM）。将基于cg - md的有限元模型与假设环氧树脂力学性能均匀的传统有限元模拟结果进行了比较，结果表明，传统有限元模拟高估了pmc的强度，并预测了基体中的对称损伤演化。另一方面，基于cg - md的有限元模拟预测了纤维-基体界面周围更真实的损伤定位。
Coarse-grained molecular dynamics (CG-MD) simulations were conducted to characterize the molecular structure and mechanical properties in the epoxy matrix around fibers in polymer matrix composites (PMCs). From these simulations, the molecular structure was quantified by measuring the free-volume hole radius distribution as a function of position from the matrix-fiber interface. Additionally, correlations between the epoxy mechanical properties and the average free-volume hole radius were established for different degrees of cross-linking. These results were then upscaled into a finite element model (FEM) of a PMC representative volume. The results from the CG-MD-informed FEM model were compared to conventional FEM simulations that assume uniform epoxy mechanical properties, and the results indicate that conventional FEM simulations overestimate the strength of PMCs and predict a symmetric damage evolution in the matrix. On the other hand, the CG-MD-informed FEM simulations predict a more realistic localization of damage around the fiber-matrix interface.