Effect of yttrium carbide on ablation behavior of zirconium carbide modified carbon/carbon composites

Effect of YC₂ on the ablation behavior of C/C–ZrC composites was investigated in an oxyacetylene flame. The chemical reactions between the oxyacetylene flame and carbides were calculated based on the principle of minimum free energy. Lots of pits are formed on the surfaces of fibers and matrices, providing more active sites and accelerating the chemical ablation. Meanwhile, the formed pits reduce the strength of fibers and matrices, increasing the mechanical breakage rate. Ablation of C/C–ZrC composites after adding YC₂ is controlled by both the chemical ablation and mechanical breakage, while ablation of C/C–ZrC composites mainly depends on the chemical ablation.