Comparative study on the ablation resistance and mechanical properties of 2.5D C/C composites reinforced with CF_MP and CF_PAN

In this contribution, we propose a new approach to enhance the ablation properties of carbon/carbon (C/C) composites. 2.5D CF_MP/C composites were obtained by mesophase pitch-based carbon fiber (CF_MP) as the reinforcing carbon fibers, which facilitates the high aerodynamic heat flow near the stagnation to be rapidly guided to the low heat flow region at the rear of the structure. The results show that the surface temperature of 2.5D CF_MP/C composites is 100 °C lower than that of 2.5D CF_PAN/C composites prepared by traditional PAN-based carbon fiber (CF_PAN), and the mass ablation rate and linear ablation rate of 2.5D CF_MP/C composites decreased from 3.307 mg/s to 1.412 mg/s and from 3.067 µm/s to 0.501 µm/s, respectively. In addition, the mechanical properties of the 2.5D CF_MP/C composites are outstanding, which will lay the foundation for their stability in ablative environments. Our work will bring new blessings for the further development of C/C composites in the aerospace field.