A Fused Cast high zirconia block containing at least 80 mass% of ZrO2 has particularly excellent corrosion resistance against molten glass and low contamination properties. Therefore, it has been widely employed as refractory materials in contact with molten glass in a glass melting furnace.

The Fused Cast high zirconia block are made of artificial synthesis of high purity raw materials through special casting process. The crystalline texture is consisting of baddeleyite. So the characteristics of these products are excellent corrosion resistance and very low blister and stoning potential. Hence, it can prevent liquid glass from pollution effectively.

 

The Fused Cast high zirconia block contains least least 80 mass% of ZrO2. The higher the proportion of the ZrO2 component in the refractory, the better the corrosion resistance against molten glass. Therefore, the refractory exhibits excellent corrosion resistance against molten glass. At the same time it does not contain a component such as CuO which can stain and color glass. Also it does not cause defects such as foreign substances derived from falling off or cracking of the refractory in the glass product. Further, it has excellent heat cycle resistance, which exhibits a very small remaining expansion even when heat cycles during its preparation or during its use.

 

However, if ZrO2 exceeds 95%, it becomes difficult to obtain a Fused Cast high zirconia block having no cracks by casting because the glass phase of the refractory will be too small. Therefore, SiO2 is added for forming the matrix glass. 

 

In the Fused Cast high zirconia block, Na2O and K2O are added as components to prevent cracking during the production of the refractory and are selective essential components such that at least either one is contained. That is, the refractory may contain Na2O alone or K2O alone, or may contain both of Na2O and K2O.

 

The Al2O3 component plays an important role in the Fused Cast high zirconia block. It can adjust the relation between the temperature and the viscosity of the matrix glass, and reduces the concentration of the ZrO2 component in the matrix glass. 

The TY-Z Series of Sunrise  Fused Cast high zirconia blocks mainly consist of TY-Z88-WS and TY-Z95-WS. They are  can be used in sidewall, throat cover, throat support, electrode block, dam block parts for a wide range of glass furnace, especially high quality and special glass furnaces such as TV glass, Borosilicate glass, Alumina silicate glass, Halogen lighting glass, Opal glass and Fiber glass.