| 摘要 |
1,244,863. Aluminous refractories and cements; mixed oxides. KAISER ALUMINUM & CHEMICAL CORP. 1 Nov., 1968 [24 Nov., 1967], No. 51999/68. Headings C1A. C1H and C1J A dense aluminous refractory is obtained by admixing a solution of alumina in a liquid solvent with at least one particulate refractory oxide insoluble in the alumina solution, immediately precipitating aluminium hydroxide in admixture with the refractory oxide, recovering and firing the admixture. An aqueous solution of NaOH is the preferred solvent. The term oxide includes their progenitors. Specified are MgO, MgO yielding materials, CaO, Ca(OH) 2 , CaO yielding material. TiO a , ZrO a , Mu compounds and their combinations Al titanate, spinel, mullite, and A1 2 0 3 containing 0À1-1À0% of TiO 2 , ZrO 2 or MnO 2 are disclosed. Preferably, the oxide has a surface area of at least 1 mÀ<SP>2</SP>/g., and the fired product is ground to have a surface area of at least 3000 cm.<SP>2</SP>/g., particularly when CaO is the added oxide, whereby a calcium aluminate cement results. |
