Template-assisted structural control and ablation resistance of ZrC-modified C/C composites

In order to improve the large-size continuous distribution of ceramic components in traditional matrix modification, which is prone to localized heat accumulation and stress concentration, this work proposes to construct a three-dimensional porous carbon template to assist in regulating the distribution size and morphology of ceramic phase within C/C composites. The porous carbon templates were prepared by the sol-gel method combined with chemical vapor deposition technique, serving as a skeleton for the dispersed ceramic components. Through the precursor impregnation and pyrolysis method, the ablation-resistant ZrC was introduced into the porous carbon, resulting in C/C-ZrC composites with a homogeneous and uniform ceramic phase distribution. Ultimately, the sample (PA-CZ) derived from the reticulated porous carbon template showed the best ablation resistance after cyclic ablation at a heat flow density of 2.4 MW/m 2 for 180 s (3 × 60 s), with mass and line ablation rates of 0.103 mg/s and 0.053 μm/s, respectively, which were 46.4% and 96.5% lower than those of conventional ZrC-modified C/C composites. Additionally, finite element simulation results showed that the introduction of a porous carbon skeleton released thermal stress inside the composite during ablation, thereby mitigating localized over-ablation and enhancing overall service performance.