Abstract Carbon/Carbon (C/C) 3D textile composites are very popular in various fields of applications such as aerospace, defence, and chemical industries due to their attractive mechanical and thermal properties. Consequently, investigation of these properties of 3D C/C textile composites has become an essential primary requirement for thermo-structural analysis of composites structures in high-temperature applications. In this study, a finite element based Representative Volume Element (RVE) has been developed to perform the thermo-mechanical analysis. Thermo-mechanical properties of 3D C/C orthogonal interlock woven fabric composite (OIWFC) and angle interlock woven fabric composite (AIWFC) are investigated. The RVE analysis for the evaluation of thermo-mechanical properties has been carried out with the implementation of multi-scale modeling techniques and periodic boundary conditions (BCs). The micro-scale analysis predicts the thermo-mechanical properties of fiber yarn/tow. Further, yarn properties are incorporated into the meso-scale model to predict the thermo-mechanical properties of 3D C/C woven fabric composites. The variation of mechanical constants and coefficient of thermal expansions (CTEs) values have been investigated within the temperature range from 300 K to 2500 K. It has been extended for the prediction of variation of thermo-mechanical properties with respect to the number of weft layers along the thickness direction of the 3D orthogonal interlock woven fabric composites. The validation study has been carried out and present FE based numerical results agree well with numerical and experimental results from the available literature.

中文翻译：

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高温环境下C/C 3D正交和角度互锁机织物复合材料的热力学建模

摘要 碳/碳 (C/C) 3D 纺织复合材料因其具有吸引力的机械和热性能而在航空航天、国防和化学工业等各个应用领域中非常受欢迎。因此，研究 3D C/C 纺织复合材料的这些特性已成为在高温应用中对复合材料结构进行热结构分析的基本要求。在这项研究中，开发了一种基于有限元的代表性体积元素 (RVE) 来执行热机械分析。研究了 3D C/C 正交互锁机织物复合材料 (OIWFC) 和角互锁机织物复合材料 (AIWFC) 的热机械性能。已通过实施多尺度建模技术和周期性边界条件 (BC) 进行了用于评估热机械性能的 RVE 分析。微观尺度分析预测了纤维纱线/丝束的热机械性能。此外，纱线特性被纳入细观模型以预测 3D C/C 机织物复合材料的热机械特性。已在 300 K 至 2500 K 的温度范围内研究了机械常数和热膨胀系数 (CTE) 值的变化。它已扩展用于预测与纬纱层数相关的热机械性能变化沿 3D 正交互锁编织织物复合材料的厚度方向。