Effects of TaC addition on the ablation resistance of C/SiC

C/SiC–TaC composites were fabricated by powder infiltration (PI) combined with chemical vapor infiltration (CVI) processing. Their ablation resistance performance was evaluated with oxyacetylene torch flame. The ablation morphology and microstructure of the tested samples were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Energy dispersive X-ray spectrum (EDS), respectively. The results indicated that TaC could improve the ablative resistance of C/SiC composites at ultra high temperatures. Liquid Ta2O5 formed due to TaC oxidation could fill the interspaces, cracks, and pores in matrix and to obstruct the diffusing channels of the ablative flames. Presence of TaC and Ta2O5 could limit the heat transfer and thus reduce the ablation. The steady SiC–TaC matrix improves the stability of composite.