Prediction of theThermo-Mechanical Properties of the SiCf/SiC RVE Model via FEM and Asymptotic Homogenization Method: Process and Implementation Details

摘要

The study focuses on characterizing the thermo-mechanical properties of SiCf/SiC using micromechanics finite element method (FEM) and multi-scale thermal-mechanical coupling asymptotic homogenization methods. A multi-scale model of fiber, fiber bundle and 2D woven SiCf/SiC has been established, while the predicted properties of the model are verified with the relevant experiments. The detailed steps to realize the micromechanical FEM are discussed, and the improvement methods have been put forward. To provide an optimal process of the micromechanical FEM based on the general software, different boundary and post-processing conditions are used and compared. Based on the traditional homogenization theory, the multi-scale thermal-mechanical coupling asymptotic homogenization method has also been developed to predict the thermo-mechanical properties of the RVE model with introduced realization. To verify the theoretical method, the properties of the 2D woven SiCf/SiC were predicted using micromechanics FEM and multi-scale thermal-mechanical coupling method, and the experimental analysis was carried out to compare with the predict results. The two methods exhibit errors in predicting the inter-layer directional performance, while the performance in other directions varies only slightly. The error between the most of the predicted values and experimental measurements is approximately 11%.