| 摘要 |
1,187,702. Fused-cast composite refractory bodies. HARBISON-CARBORUNDUM CORP. 12 Feb., 1968 [13 Feb., 1967], No. 6879/68. Heading C1J. Fused-cast, composite refractory bodies are made by casting a melt of a refractory composition in a mould of graphite or bonded refractory grain and allowing it to cool and set; a second melt of a refractory composition having a higher melting point than the first is poured into the shrinkage cavity (pipe) formed in the still-hot first refractory, remelting the large crystals lining this cavity and filling the pores and the cavity, and is allowed to cool and solidify. Suitable first melts are (a) aluminasilica, (b) alumina-zirconia-silica, and (c) chrome oxide-magnesia and are used with second melts comprising (a) alumina, (b) alumina-zirconiasilica (high ZrO 2 ) and (c) chrome oxide-magnesia (high MgO) respectively. The second refractory is preferably poured at a temperature of at least 100‹ C. above the melting point of the first refractory when a small amount of the first refractory remains molten. |
