Structural characteristics and ablative behavior of YF3 modified C/C-ZrC-SiC composites and their preparation by molten salt assisted reactive melt infiltration

In order to further improve the ablative resistance of C/C-ZrC-SiC composites, YF3 modified C/C-ZrC-SiC composites were prepared by molten salt assisted reactive melt infiltration, and the infiltration mechanism and ablative behavior of the composites were discussed. After fluorination, diffusion, adsorption and reaction of yttrium in ionic melt generated by K2ZrF6, YF3 was generated inside C/C-ZrC-SiC composites, which effectively seals the existing pores and cracks in C/C-ZrC-SiC material. YF3 modified C/C-ZrC-SiC composites can form yttrium oxide stabilized zirconia during the ablation process, and improve the ablation stability of the oxide layer compared with C/C-ZrC-SiC composites, the mass ablation rate and linear ablation rate of YF3 modified C/C-ZrC-SiC composites are reduced by 42.61% and 90.14% respectively.