Abstract: The invention relates to a process for manufacturing a refractory product, comprising the following successive steps: a) mixing of raw materials so as to form a suitable feedstock so that the block obtained in step d) comprises more than 85% of ZrO2, b) melting of said feedstock until a molten material is obtained, c) optionally, casting said molten material, d) cooling of the molten material to solidification in the form of a block, e) optionally, heat treatment, process comprising a compression operation in which a compression pressure of greater than 0.2 MPa is applied to at least one portion of the outer surface of the block obtained in step d), the compression operation beginning at a temperature above the temperature at which, in said block, tetragonal zirconia is converted to monoclinic zirconia or “phase transformation temperature”, and ending at a temperature below said phase transformation temperature.

Abstract: Fused cast refractory product comprising in percentages by weight on the basis of the oxides and for a total of 100%, —ZrO2; balance to 100%, —HfO2: <5% SiO2: 2% to 10%; —Y2O3: 0.4% to 2.0%; —CaO: 4.0% to 8.0%; —B2O3+Na2O+K2O: 0.4% to 3.0% —Al2O3: 0.3% to 2.0%; —P2O5: <0.05%; —Fe2O3+TiO2: <0.55%; —other species: <1.5%. Application in glass melting furnaces.

Abstract: 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%.

Abstract: Fused cast refractory product comprising in percentages by weight on the basis of the oxides and for a total of 100%, —ZrO2; balance to hj 100%, —Hf2O: <5% SiO2: 2% to 10%; —Y2O3: 0.4% to 2.0%; —CaO: 4.0% to 8.0%; —B2O3+Na2O+K2O: 0.4% to 3.0% —Al2O3: 0.3% to 2.0%; —P2O5: <0.05%; —Fe2O3+TiO2: <0.55%; —other species: <1.5%. Application in glass melting furnaces.

Abstract: A fused and cast refractory product containing, 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: ?4.5% B2O3: ?0.09×(Y2O3+?(CeO2+CaO+MgO))×SiO2 Al2O3: 0.3% to 2.0% Na2O+K2O: ?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%.

Abstract: The invention relates to a process for manufacturing a refractory product, comprising the following successive steps: a) mixing of raw materials so as to form a suitable feedstock so that the block obtained in step d) comprises more than 85% of ZrO2, b) melting of said feedstock until a molten material is obtained, c) optionally, casting said molten material, d) cooling of the molten material to solidification in the form of a block, e) optionally, heat treatment, process comprising a compression operation in which a compression pressure of greater than 0.2 MPa is applied to at least one portion of the outer surface of the block obtained in step d), the compression operation beginning at a temperature above the temperature at which, in said block, tetragonal zirconia is converted to monoclinic zirconia or “phase transformation temperature”, and ending at a temperature below said phase transformation temperature.

Abstract: 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%.

Abstract: A fused and cast refractory product containing, 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: ?4.5% B2O3: ?0.09×(Y2O3+?(CeO2+CaO+MgO))×SiO2 Al2O3: 0.3% to 2.0% Na2O+K2O: ?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%.

Abstract: Fused and cast refractory product including on oxides basis in percent by weight and for a total of 100%: ZrO2+HfO2 complement to 100%; 3.5% to 6.0% SiO2; 0.7% to 1.5% Al2O3; 0.10% to 0.43% Na2O+K2O; 0.05% to 0.80% B2O3; less than 0.4% CaO+SrO+MgO+ZnO; less than 0.05% P2O5; less than 0.55% Fe2O3+TiO2; less than 1.5% other species. The ratio of percentages by weight of Al2O3/(Na2O+K2O) being greater than or equal to 3.5 and the ratio of percentages by weight of B2O3/(Na2O+K2O) being between 0.3 and 2.5.

Abstract: Fused and cast refractory product including on oxides basis in percent by weight and for a total of 100%: ZrO2+HfO2 complement to 100%; 3.5% to 6.0% SiO2; 0.7% to 1.5% Al2O3; 0.10% to 0.43% Na2O+K2O; 0.05% to 0.80% B2O3; less than 0.4% CaO+SrO+MgO+ZnO; less than 0.05% P2O5; less than 0.55% Fe2O3+TiO2; less than 1.5% other species. The ratio of percentages by weight of Al2O3/(Na2O+K2O) being greater than or equal to 3.5 and the ratio of percentages by weight of B2O3/(Na2O+K2O) being between 0.3 and 2.5.