Dissolving behavior of Al2O3-SiC-C castables into blast furnace slag was examined by chemical analysis of slag after heated at 1400℃ for 2, 4 and 10h in the castable crucibles whose SiC contents were 40mass％ and 80mass％. Slag composition changed toward the castable compositions of which SiC was completely oxidized to form SiO2. Depending on the results, overall reaction rate constants for the castable dissolution into the slag were determined as 2.56×10－7 ms－1 for 40％-SiC castable and 1.85×10－7 ms－1 for 80％-SiC castable. Basing on the results, the dissolving process was concluded as follows. （1）Slag penetrates into refractories. （2）SiC in refractories are oxidized by oxygen supplied through slag film. （3）The part which includes oxidized SiC dissolves into slag immediately.

View full abstract