Introduction of fused zirconium alumina bricks with poor erosion resistance in reducing atmosphere

 
The contact between the glass phase of fused zirconium alumina brick and high temperature glass liquid will generate a high viscosity layer, which is the key to good corrosion resistance of zirconium alumina brick. This requires the glass phase softening temperature to be high, so in addition to AI2O3, ZrO2, SiO2, Na2O in the brick, other components are less.

However, because of the use of graphite lining bricks and graphite electrodes during the melting of the electric furnace, a reducing atmosphere will be generated. C and CO will reduce a part of the Fe2O3, TiO2, and SiO2 in the melt into low-priced oxides, which will increase the composition of components. .  
According to the basic principles of phase ratio, this will reduce the liquidus limit temperature.

Fused zirconia corundum bricks are characterized by stable and dense collection, and strong resistance to liquid glass erosion. There is an abnormal expansion between 900 and 1200 ° C, which is caused by the transformation of the monoclinic form of ZrO2 into the cubic form of ZrO2, which can be used as a reference for the glass pool kiln and the kiln.

When such a brick is used at high temperature, the viscosity of the glass phase is greatly reduced, a high-viscosity protective layer cannot be formed, and the glass phase has a low viscosity, and it is easy to diffuse to the high-temperature glass liquid. Will fall into the glass liquid, which will cause streaks and stones in the glass liquid.