Besides fused cast AZS blocks, fused cast high zirconia block which contains higher content of ZrO2(85%-95% ) is widely used in high quality glass furnaces and special glass furnaces, due to its excellent corrosion resistance and little pollution to glass liquid.
Fused cast high zirconia block is made of artificial synthesis of high purity raw materials through special casting process. Its crystal phase consists of a majority of baddeleyite and a little amount of glass phase. This microstructure containing monoclinic zirconia dendrites embedded into a silica-alumina glassy phase endues it with specific thermo mechanical properties.
Fused cast high zirconia block has excellent corrosion resistance and very low blistering and stoning potential. These advantages can protect liquid glass from pollution effectively. It can effectively improve the quality of glass and the service life of glass furnaces.
Fused cast AZS blocks have been widely used in glass industry for its high corrosion resistance. However, in view of the content of ZrO2 (33%-41%), the corrosion resistance is limited. Fused cast high zirconia block presents more excellent corrosion resistance due to its much higher zircon content of 85%-95%. When used in alkaline glass furnace, its corrosion resistance is not as good as that of fused cast AZS 41#, but in alkali glass furnace, it is almost not corroded by glass liquid and does not cause defects in glass.
Fused cast high zirconia block is widely used in sidewall, throat cover, throat support, electrode block, dam block parts of glass furnaces, especially high quality and special glass furnaces where the quality of glass is prior such as such as TV glass, Borosilicate glass, Alumina silicate glass, Halogen lighting glass, Opal glass and Fiber glass.