Processing and properties of cordierite-silica bonded porous SiC ceramics

Cordierite-silica bonded porous SiC ceramics were fabricated by infiltrating a porous powder compact of SiC with cordierite sol followed by sintering at 1300-1400 °C in air. The porosity, average pore diameter and flexural strength of the ceramics varied 30-36 vol%, ~ 4-22 µm and ~ 13-38 MPa respectively with variation of sintering temperature and SiC particle sizes. In the final ceramics SiC particles were bonded by the oxidation-derived SiO2 and sol-gel derived cordierite. The corrosion behaviour of sintered SiC ceramics was studied in acidic and alkaline medium. The porous SiC ceramics were observed to exhibit better corrosion resistance in acid solution.