REFRACTORY BLOCK AND GLASS FURNACE

摘要

A fused refractory product having the following average chemical composition, in % by weight on the basis of oxides and for a total of 100%: ZrO2: 30-50%; SiO2: 8-16%; Al2O3: balance to 100%; Y2O3>=50/ZrO2 and Y2O3@5%; Na2O+K2O+B2O3>=0.2% and SiO2/(Na2O+K2O+B2O3)>=5×Y2O3; CaO: @0.5%; and other oxide species: @1.5%.