A novel dual-matrix design strategy for enhanced ablation resistance of carbon fiber-reinforced composites

Low-cost, high-performance thermal protection materials are essential for next-generation solid rocket motors. Herein, we propose an innovative dual-matrix design strategy to fabricate carbon fiber-reinforced composites (C/C-PR) featuring a hybrid matrix composed of pyrolytic carbon (PyC) and phenolic resin (PR). The synergistic effect between the endothermic pyrolysis of PR and the high thermal conductivity of PyC significantly enhances the ablation resistance of the composites. Under oxyacetylene flame ablation with a heat flux of 2.38 MW/m², the C/C-PR-3 (with 65 wt% PyC and 10 wt% PR) exhibits remarkably low linear ablation rates of 1.66 μm/s in the XY direction and 1.14 μm/s in the Z direction, corresponding to reductions of 56.1 % and 78.4 %, respectively, compared to conventional C/C composites. In addition, the dual-matrix architecture facilitates energy dissipation during crack propagation, thereby contributing to the excellent mechanical performance of the C/C-PR composites. Therefore, the dual-matrix design strategy based on PyC and PR offers a promising approach for the development of high-performance and cost-effective thermal protection materials.