Ablation characteristics of mosaic structure ZrC-SiC coatings on low-density, porous C/C composites

Mosaic structure ZrC-SiC coatings were fabricated on low-density, porous C/C composites via thermal evaporation and an in-situ method. ZrC was packed in a typical lamellar mode, and the mosaic structure was formed by the deposition of Zr and Si atoms on the shallow surface of the porous C/C composites. Ablation analysis showed that the defects in the coatings originate from the boundary between the ZrC and holes created by the consumption of SiC at 2500 °C. After ablation for 200 s at 3000 °C, a dense ZrO2 layer formed on the coating surface, and the defects were sealed owing to the continuous supply of ablative components. The mass and line ablation rates of the ZrC-SiC coatings were −0.46 ± 0.15 mg cm−2·s−1 and −1.00± 0.04 μm s−1, respectively.