初始缺陷对平纹编织C/SiC复合材料热膨胀系数的影响
Effect of the Initial Defects on the Thermal Expansion Coefficients of Plain Weave C/SiC Composite

基于有限元细观计算力学（FECM）提出了一种获得平纹编织C/SiC复合材料的初始缺陷对其热膨胀系数影响关系的方法。首先通过扫描电镜（SEM）观察将初始缺陷进行分类并利用SEM图对各类初始缺陷的分布特征进行测量和统计，然后依据测量和统计结果建立含初始缺陷的宏观材料代表体积单元（RVE）和纤维束RVE有限元模型，最后采用FECM方法预测含各类初始缺陷宏观材料RVE的热膨胀系数。基于以上方法得到了各类初始缺陷与宏观材料热膨胀系数之间的定量映射关系。
An approach to obtain the effect of the initial defects on the thermal expansion coefficients of plain weave C/SiC composite was proposed based on the finite element computational micromechanics (FECM). Firstly, the initial defects were classified by using SEM observations and furthermore the measurements and statistics were carried out according to the SEM images. Then, the entire composite and fiber bundle representative volume element(RVE)models with initial defects were established according to the above-mentioned results. Finally, the thermal expansion coefficients of entire composite RVE models with initial defects were predicted by using the FECM method. The quantitative mapping relationships between all kinds of initial defects and the thermal expansion coefficients of entire composite were obtained based on the above-mentioned method