Multiscale model construction and modulus prediction of needle-punched carbon/carbon composites

In this paper, the modulus prediction of NP-C/C is completed by establishing a multiscale finite element model, and the influence weight analysis of the modulus is carried out by using the analytical homogenization method. Firstly, three Micro-RVE, including unidirectional composites, short fiber reinforced composites and porous matrix, are established to characterize the layers of NP-C/C. Then, the finite element model is used for homogenization and passed upward into Meso-RVE, and the modulus prediction is completed. Finally, the analytical homogenization method is used combined with the MATLAB® script to analyze the influence weight of the modulus by adjusting the parameters. The results show that the average errors of stiffness coefficient prediction values obtained based on the analytical homogenization method are only 6.0% relative to the experimental values, which are lower than 25.3% of the finite element model. The modulus prediction method given in this study does not need to establish a micromechanical model with complex structure, and can be directly completed by computer script when the prediction accuracy is met, which is simple and feasible.