Oxidation inhibition behaviors of the HfB2-SiC-TaSi2 coating for carbon structural materials at 1700 °C

[Display omitted] •HfB2-SiC-TaSi2 coating were prepared by spark plasma sintering method.•TaSi2 conduce to inhibit the active oxidation of SiC and loosening of HfB2 at 1700 °C, enhance the oxygen blocking ability.•Standard sample-coating sample-substrate sample mode was established.•Autogenous separation of TaSi2 and exogenous exfoliation of SiO2 glass accelerate the formation of Hf-Ta-B-Si-O glass layer.•Dispersion of dual transition metal Hf/Ta-oxide nanocrystalline particles decrease oxygen permeability of the glass layer. Oxidation inhibition behaviors of the HfB2-SiC-TaSi2 coatings fabricated by spark plasma sintering method were investigated at 1700 °C. The inerting protection capability and volume expansion effect of TaSi2 is conducive to inhibiting the active oxidation of SiC and loosening of HfB2 at 1700 °C, enhancing the structural blocking ability of the coatings. The dispersion of dual transition metal Hf/Ta-oxide nanocrystalline particles were accelerated by the autogenous separation of TaSi2 and exogenous exfoliation of SiO2 glass to form the Hf-Ta-B-Si-O compound glass layer, which conduce to decrease oxygen permeability of the compound glass layers and enhance oxidation protection efficiency of the coatings.