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

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.