refractories for zro2. al2o3 and sio2 enthaltendem schmelzguss

摘要

Fusion-cast refractory with the overwhelming majority of its crystalline mass being zirconia crystals and containing siliceous glass phase interstitially between the zirconia crystals. Composition analytically consists of, by weight, at least 62 percent Zr02, not more than 24 percent Si02, at least 1 percent A1203 not exceeding the amount of Si02, 0 to 10 percent oxide of Li, Na, K, Rb, Cs, Be, Mg, Ca, Sr, Ba or mixtures thereof, 0 to 4 percent fluorine, and not more than 1 percent Fe203 plus Ti02. Useful in lining glass melting tanks. Characterized by being substantially crack-free as manufactured and less subject to cracking in service, and by minimal stoning, corrosion, and blistering in contact with many molten glasses, especially aluminosilicate, borosilicate and other glasses melted at temperatures of 1,550 DEG C. or higher.