| abstract |
A refractory having a high zirconia content is provided. SOLUTION: The weight percentage based on oxide, and the total is 100%. ZrO 2 : 100% residual, Hf 2 O: <5% SiO 2 : 2% to 10%, 0.9% <Y 2 O 3 + CeO 2 + CaO + MgO ≦ 4.0%, B 2 O 3 : ≦ 4.5% B 2 O 3 : ≧ 0.09 × (Y 2 O 3 +1/3 (CeO 2 + CaO + MgO)) × SiO 2 Al 2 O 3: 0.3% ~2.0 %, Na 2 O + K 2 O: ≦ 0.5%, P 2 O 5 : <0.05%, Fe 2 O 3 + TiO 2 : <0.55%, Other species: <1.0%, A melted and cast molded refractory containing, but having a Y 2 O 3 content of 0.5% or more or a CeO 2 + CaO + MgO content of 2% or more. [Selection figure] None |