Computational Prediction of SiC_f/SiC Stiffness and Thermal Residual Stress by 3D Micro-scale FEA Methods

Ceramic matrix composites (CMCs, e.g. SiC_f/SiC) are applied widely in hot-section components of aeronautics and astronautics. The macroscale mechanical properties of CMCs and the thermal residual stress (TRS) created during preparation can be easily obtained by standard tests. However, in the material design stage, it will result in waste only through testing validation. Precise virtual simulation technology (VST) is extremely useful on predicting materials’ performance and giving optimal strategies to materials designers. Under this mean, the present work is mainly focusing on predicting the macro-stiffness and TRS for SiC_f/SiC composites. The microscale representative volume elements (RVE) model with period boundary condition (PBC) is used to calculate the elastic modulus in fiber direction and two fiber’s normal directions adn shear modulus of in-plane and out-plane. Besides, in the 3D microscale FEA model specialized for TRS calculation, parameters effects of homogeneous and anisotropic interphase modulus and interphase thickness are investigated.