二维编织陶瓷基复合材料偏轴拉伸力学性能预测

基于二维编织C/SiC复合材料的细观结构，建立了碳纤维丝/热解碳界面/SiC基体和纤维束/表层SiC基体两种尺度下的细观单胞模型，通过有限元方法计算碳纤维丝/热解碳界面/SiC基体模型的等效弹性常数和强度，然后代入纤维束/表层SiC基体模型中计算，并引入Tsai-Wu失效准则，考虑不同失效模式的损伤，建立了二维编织C/SiC复合材料的渐进损伤模型，模拟了其偏轴拉伸应力-应变行为。针对该模型，阐述了二维编织C/SiC复合材料单胞模型在复杂应力状态下其纤维束的损伤过程。数值模拟结果与实验数据吻合较好，验证了模型的有效性，为该种材料的力学性能分析提供了一种有效方法。

Mechanical properties prediction of 2D braided ceramic matrix composites under off-axial tension

Based on the meso-structure of 2D braided C/SiC composites, two micromechanical models were presented to simulate the progressive damage behavior of 2D braided C/SiC composites that subjected to off-axial tension. The equivalent elastic constants and strength of the carbon fiber/pyrolytic carbon interface/SiC matrix model were calculated by the finite element method and then applied to the yarn/SiC matrix model. The Tsai-Wu failure criteria that considers different damage modes was utilized to set up the progressive damage model, and the stress-strain relation of 2D braided C/SiC composites was simulated. The damage model explains the damage evolution of 2D braided C/SiC composites tows in the complex stress state. The numerical results accurately capture the experimental data, which demonstrates the validity of the proposed analytical model. And this model provides a method to predict the mechanical properties of 2D braided C/SiC composites.