Compressive response of hybrid 3D woven textile composites (H3DWTCs): An experimentally validated computational model
Compressive response of hybrid 3D woven textile composites (H3DWTCs): An experimentally validated computational model
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DOI：
10.1016/j.jmps.2018.08.018
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发表时间：
2019-01-01
影响因子：
5.3
通讯作者：
Yen, Chian-Fong
中科院分区：
文献类型：
--
作者：
Patel, Deepak K.;Waas, Anthony M.;Yen, Chian-Fong
混合三维机织纺织复合材料（H3 DWTCs）的压缩响应进行了实验研究，所获得的结果被用来激励的力学模型的发展，计算实现。所考虑的H3 DWTC由碳、玻璃和凯夫拉纤维丝束以及聚合物基体材料组成。建模方法的新奇在于，在微观力学模型中，包括使用高分辨率Micro-CT方法测量的微观结构级复合结构的原位几何缺陷，并仔细地将宏观响应的细节与微观结构联系起来。对失效样本进行的详细Micro-CT研究揭示了主要失效机制的详细信息，其中包括多个渐进性扭结带和基质损伤，这些损伤是限制抗压强度的原因。在数值预测模型的开发中，莫尔-库仑（MC）准则被用来模拟基质压缩破坏结合在周围的纤维丝束外的基质中的涂抹裂纹的方法（SCA）。纤维丝束被建模为宏观均匀的，但两个尺度的方法开发，使用分析封闭形式的微观力学模型在每个积分点的均匀化纤维丝束，允许计算纤维和基质的应力状态内丝束。实验结果表明，碳纤维的抗压强度决定了在碳丝束扭结带故障的开始，而玻璃纤维丝束的抗压强度决定了可达到的最大载荷。这表明，不同方面的压缩响应有关的组成结构特性。实验结果和观察预测的计算模型，这是有用的结构应用损伤容限和强度许用规定的设计包络线的边界。(C)2018爱思唯尔有限公司版权所有
The compressive response of hybrid 3D woven textile composites (H3DWTCs) is studied experimentally and the results obtained are used to motivate the development of a mechanics model, implemented computationally. The H3DWTCs considered consist of carbon, glass and kevlar fiber tows and a polymer matrix material. The novelty of the modeling approach is to include the in-situ geometric imperfections of the microstructural level composite architecture, measured using high resolution Micro-CT methods, in the micromechanics model and to carefully relate the details of the macroscopic response to the microstructure. A detailed Micro-CT study of the failed specimens reveals details of the dominant failure mechanisms which include multiple and progressive kink banding and matrix damage, responsible for limiting compressive strength. In the numerical predictive model development, the Mohr-Coulomb (MC) criterion is used to model matrix compressive failure in combination with the smeared crack approach (SCA) in the surrounding matrix outside of fiber tows. The fiber tow is modeled as macroscopically homogeneous, but a two-scale method is developed that uses an analytical closed-form micromechanics model at each integration point of the homogenized fiber tow which allows to calculate the fiber and matrix stress states within a tow. The experimental results suggest that carbon fiber compressive strength dictates the initiation of kink banding failure in carbon tows, while glass fiber tow compressive strength dictates the maximum load attainable. This suggests that different aspects of the compressive response are related to constituent structural properties. The experimental results and observations are predicted by the computational model which is useful for structural applications where damage tolerance and strength allowables dictate the boundaries of the design envelope. (C) 2018 Elsevier Ltd. All rights reserved.