Refractory brick
AssigneeShinagawa Refractories Co., Ltd.
InventorsRyosuke Nakamura, Hiroyuki Shikama, Hisashi Tomiya, Hisaharu Sasaki
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Abstract
A refractory brick having durability equal to alumina-magnesia castable materials, which is especially suitable for a ladle for steel making is provided. A refractory brick prepared by using an alumina raw material and a magnesia raw material containing 90% by mass or more of a fine powder of not more than 0.5 mm, press molding and then heat treating at 100° C. or higher and not higher than 1,150° C., the refractory brick containing Al2O3 and MgO in a total sum of 90% by mass or more, from 4 to 16% by mass of MgO, from 0.5 to 5% by mass of SiO2, and Na2O and K2O in a total sum of from 0.3 to 2% by mass, with the remainder being inevitable impurities and Al2O3.
Claims2
A refractory brick prepared by using an alumina raw material and a magnesia raw material containing 90% by mass or more of fine powder of not more than 0.5 mm and containing particles of which particle size exceeds 90 μm, adding silica sand, a silica stone powder, an agalmatolite powder, silica flour or a refractory clay singly or in admixture, press molding and then heat treating at 100° C. or higher and not higher than 1,150° C., the refractory brick containing Al2O3 and MgO in a total sum of 90% by mass or more, from 4 to 16% by mass of MgO, from 0.5 to 5% by mass of SiO2, and Na2O and K2O in a total sum of from 0.3 to 2% by mass, with the remainder being inevitable impurities and Al2O3 and having a free expansion coefficient at 1,500° C. of from 2 to 5% and an expansion coefficient under a load of 1 MPa of from −6 to 1%.
Dependencies are inferred from the claim text.