High zirconia fused cast refractories
AssigneeAsahi Glass Company, Limited
InventorsToshihiro Ishino, Otojiro Kida, Yoshihisa Beppu
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Abstract
High zirconia fused cast refractories which include as chemical components of refractories in weight %, 85 through 91% of ZrO.sub.2, 7.0 through 11.2% of SiO.sub.2, 0.85 through 3.0% of Al.sub.2 O.sub.3, 0.05 through 1.0% of P.sub.2 O.sub.5, 0.05 through 1.0% of B.sub.2 O.sub.3 and 0.01 through 0.12% of a summed amount of K.sub.2 O and Na.sub.2 O, wherein the weight % of K.sub.2 O is not smaller than the weight % of Na.sub.2 O.
Claims9
High zirconia fused cast for refractories comprising, in weight %, 85 through 91% of ZrO.sub.2, 7.0 through 11.2% of SiO.sub.2, 1.1 through 3.0% of Al.sub.2 O.sub.3, 0.05 through 1.0% of P.sub.2 O.sub.5, 0.05 through 1.0% of B.sub.2 O.sub.3 and 0.01 through 0.12% of a summed amount of K.sub.2 O and Na.sub.2 O, wherein the weight % of K.sub.2 O is not smaller than the weight % of Na.sub.2 O;
- wherein said high zirconia fused cast refractories have a volume increase smaller than 10% after 40 thermal cycles between 800.degree. C. and 1250.degree. C.
High zirconia fused cast refractories comprising, 85 through 91 wt. % of ZrO.sub.2, 7.0 through 11.2 wt. % of SiO.sub.2 and 1.1 through 3.0 wt. % of Al.sub.2 O.sub.3, having an electrical resistivity of 1500.degree. C. not smaller than 100 .OMEGA.cm, show a volume increase smaller than 3% after 40 thermal cycles between 800.degree. C. and 1250.degree. C. and show no chipping in there heat up.
Dependencies are inferred from the claim text.