Spinel type fused refractory product
AssigneeAsahi Glass Company, Limited
InventorsKoji Oohasi, Yutaka Hosoda, Toshio Kitamura, Eiichi Kudo
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Abstract
A spinel type dense fused refractory product having excellent corrosion resistance comprises a crystalline structure consisting essentially of more than 50% by weight of composite spinel phase comprising RO component selected from MgO and FeO and R'.sub.2 O.sub.3 component selected from Cr.sub.2 O.sub.3, Al.sub.2 O.sub.3 and Fe.sub.2 O.sub.3 and periclase phase and a small content of glass matrix phase which consists essentially of the following constituents, analytically on a weight basis; a ratio of Cr.sub.2 O.sub.3 to Al.sub.2 O.sub.3 of 3.5 to 5.5; and 20% to 40% of MgO; 1.5% or less of CaO; 15% or less of Fe.sub.2 O.sub.3 (FeO is also calculated for Fe.sub.2 O.sub.3) and 5% or less of SiO.sub.2.
Claims5
A spinel type dense fused refractory product having excellent corrosion resistance which comprises a crystalline structure consisting essentially of (a) 65%-80% by weight of composite spinel phase comprising RO component selected from MgO and FeO and R.sub.2 O.sub.3 component selected from Cr.sub.2 O.sub.3, Al.sub.2 O.sub.3 and Fe.sub.2 O.sub.3 :
- (b) 19% to 30% periclase phase and (c) 1% to 8% of glass matrix phase;
- which product consists essentially of the following constituents, analytically on a weight basis:
- 20% to 40% of MgO;
- 30% to 60% of Cr.sub.3 O.sub.3 ;
- 5% to 15% of Al.sub.2 O.sub.3 ;
- 0.5% to 5% of SiO.sub.2 ;
- 0.3% to 1.5% of CaO;
- and 15% or less of Fe.sub.2 O.sub.3 ;
- wherein the ratio of Cr.sub.2 O.sub.3 to Al.sub.2 O.sub.3 is 3.5 to 5.5.
Dependencies are inferred from the claim text.