High zirconia fused cast refractory
View Patent ↗To provide a high zirconia fused cast refractory having high durability, which hardly has cracks during the heating, by temperature changes during use and during the cooling at the time of suspension of operation. A high zirconia fused cast refractory which has a chemical composition comprising from 86 to 96 mass % of ZrO 2 , from 2.5 to 8.5 mass % of SiO 2 , from 0.4 to 3 mass % of Al 2 O 3 , from 0.4 to 1.8 mass % of K 2 O, at most 0.04 mass % of B 2 O 3 , at most 0.04 mass % of P 2 O 5 and at most 3.8 mass % of Cs 2 O and containing substantially no Na 2 O.
1. A high zirconia fused cast refractory which has a chemical composition comprising from 86 to 96 mass % of ZrO 2 , from 2.5 to 8.5 mass % of SiO 2 , from 0.4 to 3 mass % of Al 2 O 3 , from 0.4 to 1.8 mass % of K 2 O, at most 0.04 mass % of B 2 O 3 , at most 0.04 mass % of P 2 O 5 and at most 3.8 mass % of Cs 2 O and comprising substantially no Na 2 O.
2. The high zirconia fused cast refractory according to claim 1 , comprising from 0.05 to 3.5 mass % of Cs 2 O.
3. The high zirconia fused cast refractory according to claim 2 , comprising from 0.05 to 0.7 mass % of Cs 2 O.
4. The high zirconia fused cast refractory according to claim 1 , wherein the content of Na 2 O is at most 0.02 mass %.
5. The high zirconia fused cast refractory according to claim 1 , wherein the total content of Fe 2 O 3 and TiO 2 is at most 0.3 mass %.
6. The high zirconia fused cast refractory according to claim 1 , wherein the total content of Y 2 O 3 and CaO is at most 0.3 mass %.
7. The high zirconia fused cast refractory according to claim 1 , wherein the content of CuO is at most 0.02 mass %.
8. The high zirconia fused cast refractory according to claim 1 , which is for a glass melting furnace.