Enhancement of ablative property and thermal conductivity of CeB6 modified C/C-SiC-ZrC composites through high temperature treatment

CeB 6 modified C/C-SiC-ZrC composites were designed by using slurry infiltration and precursor infiltration and pyrolysis method combined with high temperature treatment. Experimental results show that both adding CeB 6 and heat treatment could improve the ablative performance of C/C-SiC-ZrC composites significantly. Thermal conductivity of the composites can be optimized by high temperature treatment, accelerating the heat transfer of the composites in the ablation process. The heat treated C/C-SiC-ZrC-CeB 6 composites with high content of CeB 6 exhibit enhanced ablation performance at about 2600 °C, and the mass and linear ablation rates of the composites are 0.37 mg/s and 3.33 μm/s, respectively. The phase transition of ZrO 2 phases was suppressed by (Zr 1-x Ce x )O 2 solid solution phases which were uniformly distributed at the grain boundaries of ZrO 2 grains, resulting in the superior stability of the ZrO 2 scales under the scouring of the oxyacetylene flame.