考虑孔隙和微裂纹缺陷的C／C-SiC编织复合材料等效模量计算  

Numerical computing of effective modulus of woven C/C-SiC composites including porosities and micro-cracks

作　　者：汪海滨[1] 张卫红[1] 杨军刚[1] 许英杰[1] 曾庆丰[2] 

机构地区：[1]西北工业大学中法并行工程联合实验室,高性能计算中心,现代设计与集成制造教育部重点实验室,西安710072 [2]西北工业大学超高温结构复合材料国防科技重点实验室,西安710072

出　　处：《复合材料学报》2008年第3期182-189,共8页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金(9040501650775184);973计划(2006CB601205);863项目(2006AA04Z122);教育部博士点基金(20060699006);航空科学基金(2006ZA53006);陕西省科技计划项目(2006K05-G25);西安应用材料创新基金(XA-AM-200705)

摘　　要：通过观察C/C-SiC复合材料组元分布的扫描电子显微镜(SEM)照片,获得了C/C-SiC复合材料化学气相渗透(CVI)制备过程中产生孔隙和微裂纹的几何信息。在此基础上,建立了包含孔隙和微裂纹的C/C-SiC微结构有限元模型,并利用均匀化等效计算方法预测了平纹编织C/C-SiC复合材料的模量。针对CVI沉积方式制备的2组不同的C/C-SiC复合材料,实验测试与等效计算结果表明:基于SEM照片建立的C/C-SiC纤维束和复合材料微结构有限元模型,能够反映CVI工艺制备C/C-SiC中孔隙和微裂纹的分布状况;计算结果与实验数据有良好的一致性,数值计算可有效预测C/C-SiC编织复合材料的模量。The woven carbon fiber reinforced C-SiC binary matrix （C/C-SiC） composite manufactured by chemical vapor infiltration （CVI） method was investigated. Based on the material tomography of scanning electron microscopy （SEM）, distributions of porosities and micro-cracks were identified and included in the finite element model of C/C- SiC composites. The homogenization method was used for the evaluation of effective modulus of woven C/C-SiC composites. The results of the numerical computing and experimental tests were compared for two cases of C/C-SiC composites with different layer thickness. It is shown that the proposed finite element models of C/C-SiC can characterize physically the real situation of the involved porosities and micro-cracks related to the CVI process. The numerical results of effective modulus agree reasonably with the experimental ones.

关 键 词：C/C—SiC复合材料 化学气相渗透 孔隙 微裂纹 均匀化方法 

分 类 号：TB332[一般工业技术—材料科学与工程]