Catalytic Fabrication of SiC/SiO2 coated graphite and its behaviour in Al2O3–C castable systems

Abstract SiC/SiO 2 coated graphite was prepared via a combined sol-gel coating and catalytic conversion route, using graphite flake and tetraethyl orthosilicate as the starting materials, and Fe(NO 3 ) 3 ·9H 2 O as the catalyst precursor. X-ray diffraction analysis and microstructural examination revealed that a homogeneous coating comprising SiC and cristobalite (SiO 2 ) and covering the whole surface of graphite was formed. As prepared SiC/SiO 2 coated graphite exhibited better oxidation resistance and water wettability than its uncoated counterpart. Also, oxidation resistance and slag corrosion resistance of a model Al 2 O 3 –C castable using coated graphite as a carbon source were better than in the case of its counterpart using uncoated graphite.