摘要 |
PCT No. PCT/GB94/02127 Sec. 371 Date Mar. 13, 1996 Sec. 102(e) Date Mar. 13, 1996 PCT Filed Sep. 30, 1994 PCT Pub. No. WO95/11870 PCT Pub. Date Mar. 4, 1995A refractory article of manufacture comprises an article of graphite-alumina refractory material coated with at least one mineral having a sheet structure and a refractory oxide bond. The coating protects the article against thermal shock. A typical mineral having a sheet structure may be talc, a mica, vermiculite, antigorite, kaolinite, montmorillonite, pyrophyllite, or combinations of these materials. A typical refractory oxide bond is formed from alumina gel, silica sol, alumina sol, zirconia sol, or combinations of these materials (such as a combination of alumina gel and cationic silica sol). The coating may also contain a minor proportion of fibrous material and a minor proportion of particulate refractory filler other than the mineral having a sheet structure, and a portion of the mineral content of the mineral forming the sheet structure may include graphite. The coating may be in the form of a fluid having 5-50% by weight of mineral having a street structure, 20-60% by weight of refractory oxide binder for forming the refractory oxide bond, and 20-50% by weight of carrier liquid. The carrier liquid is removed by drying (e.g. in an oven). |