Simulation Study on Compression Properties of Needle-Punched Carbon/Carbon Composites after High Temperature Oxidation

Needle-punched carbon/carbon composites (NP C/Cs) are extensively utilized in aerospace applications due to their superior mechanical performance at elevated temperatures. However, it is susceptible to oxidation in high-temperature, oxygen-rich environments, leading to alterations in the structure and volume content at the material interfaces, which ultimately compromises their mechanical properties. In this study, the shape evolution curve of circular arc fiber during steady state ablation is derived. Utilizing embedded element technology, an embedded solid beam mixed element model was developed to predict the axial compression behavior of NP C/Cs both before and after oxidation. This approach not only simplifies the model but also enhances computational efficiency. The findings indicate that as the mass loss ratio increases from 0% to 16.84%, the predicted residual elastic modulus ratio decreases from 100.00% to 58.34%, while the residual compressive strength ratio drops from 100.00% to 59.82%. The strong correlation between experimental and simulation results for residual modulus and strength ratios validates the proposed model, confirming its effectiveness in predicting the mechanical performance of NP C/Cs under oxidative conditions.