The effect of the addition of between V2O5 and SiO2 on the firing behavior of SiC refractory was examined. The green compacts were fabricated by aqueous slip casting with sodium silicate as a dispersant from the coarse and fine powders of SiC containing SiO2 and V2O5 as bonding agents. In general, the slip casting gave the high packing density of green compact comparing with that of pressing. The fired SiC compacts with 1.0 mass％ SiO2 and 1.5mass％ V2O5, which were optimum amounts of bonding agents, fired at 1000～1400℃ indicated above 150MPa of the bending strength. This value was almost twice strength without V2O5. The microstructural observation using an SEM-EDX and the measurement of XRD were found that the enhancement of strength should be attributed to the formation of crystobalite around the SiC particles adherently. Crystobalite was formed mainly by the reaction of SiC and V2O5.

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