Al2O3-SiC-C castables are one of the advanced refractories which are favored in many applications because of the high corrosion resistance, thermal shock resistance, thermal conductivity and mechanical strength. They are mainly used in troughs and slag/metal runners of blast furnaces. In Iran for lining of runners, ramming mixes which are the oldest refractories used for such application are still in use. In this study a typical Al2O3-SiC-C castable was selected and the influence of amount of silicon carbide on properties was investigated. Bulk density, apparent porosity, permanent linear change, cold crushing strength and cold modulus of rupture of samples was determined at 110, 1000, 1250 and 1500°C. Phase analysis was carried out on all specimens fired at different temperatures.
Mean while crucible and finger corrosion techniques were performed to determine corrosion resistance of the samples. Micro structural investigations were also done on all fired and corroded specimens.
The results showed that increasing SiC content caused a slight increase in water demand, as well as decrease in mechanical strength and caused porosity increase. However, bulk density was not affected significantly. Corrosion resistance was also decreased.
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