REFRACTORY PRODUCT HAVING HIGH ZIRCONIA CONTENT.

摘要

The invention relates to a molten, fluid refractory product comprising, in weight percentages on the basis of the oxides and for a total of 100%: - ZrO2: remainder up to 100% - Hf2O: < 5% - SiO2: 2% to 10% - 0.9 % < Y2O3+ CeO2 + CaO + MgO < 4.0 % - B2O3: â ¤ 4.5% - B2O3: â ¥ 0.09 x (Y2O3 + 1 /3 (CeO2 + CaO + MgO)) x SiO2 - Al2O3: 0.3% to 2.0% - Na2O + K2O; â ¤ 0.5% - P2O5: < 0.05% - Fe2O3 + TiO2: < 0.55% - other species: < 1.0%, as long as the Y2O3 content is no lower than 0.5% and the CeO2 + CaO + MgO content is no lower than 2%. The invention can be used in glass melting furnaces.