The ablation behavior of ZrB2-SiC coating prepared by shrouded plasma spray on SiC-coated graphite

ZrB2-SiC coating was generated on SiC-coated graphite using shrouded plasma spray (SPS). The samples' ablation features were assessed by an oxyacetylene torch flame. The mass and linear ablation rates of SiC coating are 2.17 × 10−3 g s−1 and 2.3 × 10−3 mm s−1, while those for ZrB2-SiC coating are as 1.67 × 10−5 g s−1 and 0.04 × 10−5 mm s−1. The ZrB2-SiC coating considerably increased the ablation resistance in comparison to the SiC coating. The ZrO2 layer was produced from ZrB2-SiC oxidation and acted as a thermal barrier. Also, this layer prevents the diffusion of more oxygen to the inner SiC layer.