| 摘要 |
1478904 Refractory bricks OTAVI MINENUND EISENBARN-GES 2 Aug 1974 [2 Aug 1973] 34258/74 Headings ClJ and ClH A fired refractory insulating brick comprises a refractory binding framework and expanded perlite, the brick having substantially closed pores, each such pore being externally defined by a glazed outer skin formed during firing by the melting of a grain of expanded perlite. Binding agents include Portland cement, aluminous cement, phosphates, silicates (e.g. water glass), lime, and clay. The bricks may be made by shaping and firing. Shrinkage during firing may be compensated for by addition of kyanite to the raw materials. Pore carriers, e.g. chamotte, kieselguhr, vermiculite and asbestos may be included in the raw materials in an amount up to 80 wt. per cent. The preparation of bricks from expanded perlite, chamottes A and B, aluminous cement and water (Example 1), from expanded perlite, chamotte A, aluminous cement, kyanite and water (Example 2), from expanded perlite, chamotte A, ohamotte B and aluminium phosphate (Example 3) and from expanded perlite, aluminous cement, and water (Example 4) are described. |
