Ablation performance of C/C-ZrC-SiC composites with in-situ YSi₂-doped ZrC-SiC-ZrSi₂ coating under oxyacetylene torch

C/C-ZrC-SiC composites with in-situ formed ZrC-SiC-ZrSi₂ coating (ZS) and YSi₂-doped ZrC-SiC-ZrSi₂ coating (YZS) were prepared by reactive melting infiltration (RMI). The ablation behavior was investigated under the oxyacetylene torch with heat fluxes of 2.38 and 4.18 MW/m². Results showed that YZS exhibited a more integrated scale and lower ablation rates after ablation due to the doping of YSi₂. The Y₂O₃ and ZrO₂ phases could form substitutional solid solutions during ablation, which had a dense structure and could lower the surface temperature of composites. Meanwhile, Y₂O₃ could inhibit the phase transition of ZrO₂, promoting the sintering of ZrO₂ during ablation.