Why is fused zirconium alumina brick better than fused mullite brick in resistance to liquid glass erosion?

Fused zircon alumina brick is also called AZS. Fused zircon alumina brick is abbreviated as AzS, and it is based on Al: O-zr0rSO2.
 

The three chemical components of the ternary phase diagram are arranged in order of their content. Al2Os is A, zrO2 is z, SO2 is the national standard.
 

Fused zircon corundum bricks have better resistance to liquid glass erosion than fused mullite bricks for the following reasons.
 

①The main crystal phase in zirconium corundum brick is coexisting corundum and oblique wrong stone, and these two crystal phases have good corrosion resistance.

② The glass phase in the zirconium corundum brick is filled between the above-mentioned crystal phases. This glass phase is corroded by the high-temperature glass liquid to generate a very high viscosity sodium feldspar glass. The viscosity is greater because a certain amount of ZrO2 is melted in it. The layer of highly viscous glass remains on the surface of the brick and does not spread easily, thus protecting the brick. The corrosion resistance of fused zircon corundum bricks increases with the increase of ZrOz content. Because the melting temperature of ZrO2 is as high as about 2700C, and it has high ability to resist acids, alkalis and glass liquids.
 

Due to the above advantages, fused zirconium corundum bricks are not only used in high temperature and severely eroded parts in contact with glass liquid, but also widely used in glass melting furnace superstructures.