关键词: 界面结合, 平纹织物复合材料, 多尺度模型, 面内剪切, 有限元分析

Abstract: Carbon fiber composites have been widely applied in fields such as aerospace and transportation due to their exceptional specific strength and specific modulus. Unlike traditional metal materials, the interfacial interactions within composites directly influence their stress transfer and strength performance. Compared with unidirectional fiber-reinforced composites, the weaving structure of textile composites is more complex, making the interfacial bonding between yarn-yarn and yarn-matrix particularly crucial. Therefore, studying the influence of interfacial bonding characteristics on the in-plane shear behavior of textile composites holds significant theoretical and practical importance.​ Based on zero-thickness cohesive elements and a multi-scale analysis approach, this paper predicts the equivalent properties of yarns under different interfacial bonding conditions through microscale modeling. Meanwhile, a mesoscale model that accounts for the interfacial properties between yarn-yarn and yarn-matrix is developed. The study reveals that the fiber-matrix interfacial strength significantly affects the transverse tensile strength and in-plane shear strength of yarns. When the fiber-matrix interface is fixed, the transverse tensile strength and in-plane shear strength of yarns increase by 79.31% and 39.53%, respectively. In addition, the analysis results of the shear modulus of the composites show a deviation of 9.97% from the experimental data, which is within the allowable error range (10%). The in-plane shear behavior of textile composites is more sensitive to the yarn-matrix interface than to the yarn-yarn interface. When the yarn-matrix interfacial strength is enhanced, the shear modulus of the textile composite increases by 21.37%. Specifically, the primary failure mode of the yarns is matrix damage, accounting for up to 60%, which is one of the important factors leading to the nonlinear behavior of textile composites. Additionally, a systematic analysis of the damage extent in various components of the textile composite is conducted, unveiling the influence of interfacial bonding characteristics on stress transfer between yarn-yarn and yarn-matrix interfaces.​ Therefore, the interfacial bonding model established in this paper can accurately predict the in-plane shear behavior of textile composites. It reveals the interaction relationship between yarns and the matrix, providing a reference for optimizing the interface design of textile composites.​

Key words: interfacial bonding, plain weave fabric composite, multi-scale model, in-plane shear, finite element analysis