Thermal conductivities of plain woven C/SiC composite: Micromechanical model considering PyC interphase thermal conductance and manufacture-induced voids

In this paper a micromechanical model considering PyC interphase thermal conductance and manufacture-induced voids is proposed to predict the thermal conductivities of plain woven C/SiC composite. This model is based upon the analysis of the representative volume element (RVE) models of composite. The modeling strategy starts with a geometrical description and finite element discretization on two scales consisting of the fiber yarn modeling (fiber-scale) followed by a woven fabric modeling (yarn-scale). The PyC interphase is introduced in the fiber-scale modeling while the large voids at the intersection of orthogonal yarns are included in the yarn-scale modeling. Experiments are conducted to measure the thermal conductivities of plain woven C/SiC samples from room temperature to 800 degrees C temperature. The satisfied agreement with experimental data has highlighted the predictive capability of the proposed micromechanical model. Finally, a parametric study is performed using the presented model to investigate the effects of PyC interphase thermal conductance and manufacture-induced voids on the thermal conductivities of composite.