Effects of graphene addition on the microstructure and anti-ablation properties of C/C-SiC composites prepared by precursor impregnation and pyrolysis

Graphene was introduced into C/C-SiC composites via pressureless impregnation to enhance the mechanical and thermal properties of the composites. The effects of various graphene contents on the mechanical and ablative performances of C/C-SiC composites were investigated. The results showed that the ultimate bending stress and compressive stress of the C/C-SiC composites increased by 28.98% and 23.64%, respectively, after adding 7.25% graphene. Moreover, the ablation rates of the composites were vastly decreased after adding a slight graphene content (2.13%). However, the ablation rates increased with increasing of graphene content, indicating that the benefit of introducing graphene on the ablation property decreased, which was mainly ascribed to the relative reduction in the SiC content. As a result, introducing slight graphene into C/C-SiC composites had the greatest benefit on the anti-ablation performance.