On the oxidation behavior of ZrB2-SiC-VC composites

In this study, near-fully dense ZrB2-SiC-VC (75-20-5 vol%) composite was manufactured through hot pressing at 1850 degrees C under the pressure of 40 MPa for 60 min. Then the oxidation examination of the composite was carried out under different durations and temperatures. The microstructure and phase evolution after hot pressing and oxidation processes were examined by scanning electron microscopy, and X-ray diffractometry. The VC addition led to the formation of ZrC and VSi2 phases, which assisted the densification of the composite by removing ZrO2 from the particles' surface. The oxides of ZrO2, SiO2, ZrSiO4, V2O5, and VO2 formed distinct layers on the sample during the oxidation at 1700 degrees C for 4 h with a parabolic regimen and activation energy of 177.5 kJ/mol.