Oxidation Behavior at 1600 °C of Si-SiC-ZrB2 Composites Produced by Si Reactive Infiltration

Si–SiC–ZrB2 are produced by the reactive infiltration with molten silicon in porous SiC–C–ZrB2 preforms. It is observed that oxidized Si–SiC–ZrB2 ceramics present a layered structure composed of an outer layer of silica and a borosilicate glass intermediate layer with ZrO2 particles and the unoxidized bulk material. The graphs show that the passivation is very effective already after 5 min of oxidation. The thermograms do not vary significantly when the oxidation times are increased.