摘要 |
<p>The present invention relates to a fused refractory product having the following average chemical composition, as a percentage by weight on the basis of the oxides and for a total of 100%: ZrO2: 60.0%-80.0%; SiO2: 4.0%-10.0%; Al2O3: balance to 100%; Y2O3≰5.0%; Na2O+K2O+B2O3≧0.3% and SiO2/(Na2O+K2O+B2O3)≧5.0; other oxide species:≰2.0%; the ratio of the ZrO2/Al2O3 weight contents being between 2.0 and 6.0.</p> |