Ablation behavior of Cf/ZrC-SiC and Cf/SiC composites produced by precursor infiltration and pyrolysis combined with gaseous silicon infiltration

The ablation behavior of C f /ZrC-SiC and C f /SiC composites by a novel combined process was studied. The FLUENT calculation indicates high thermophysical gradients of oxyacetylene torch, which determines ablation behavior of the composites. The integrated effects of oxidation, evaporation and mechanical factor result in discontinuous SiO 2 scale, thus causing severe ablation of C f /SiC composites. As for C f /ZrC-SiC composites, the joint action of ZrO 2 and SiO 2 bilayer structure provides good ablation and oxidation resistance. Nevertheless, a little erosion of C f /ZrC-SiC composites occurs by the integrated effects of chemical and physical erosion, and the mechanical factor plays a more important role. • The growth of ZrC content accounts for better ablation performance of C f /ZrC-SiC composites by a novel PIP-GSI process. • The FLUENT calculation indicates high thermophysical gradients of oxyacetylene torch, which determines the ablation behavior. • The integrated effects of oxidation, evaporation and mechanical factor result in discontinuous SiO 2 scale, thus causing severe ablation of C f /SiC composites. • The joint action of ZrO 2 and SiO 2 bilayer structure provides good ablation and oxidation resistance for C f /ZrC-SiC composites.