| 摘要 |
1,145,402. Refractory materials; carbides. FMC CORP. 9 May, 1966 [23 Oct., 1965], No. 20480/66. Headings C1A and C1J. High-temperature-resistant materials, in the form of films, fibres, plates for example, are made by shaping and heating at least one glassforming oxide (i.e. B 2 O 3 , SiO 2 , Al 2 O 3 , ZrO 2 ) and a cellulosic substance in a ratio of 0À2: 1 to 2: 1 to a temperature of 200-250‹ C., preferably in an oxygen-bearing atmosphere until structurally held water is released; then heating in an inert atmosphere to 400-450‹ C. until the cellulose substance is decomposed and finally heating in the presence of a pyrolysable carbonaceous substance (e.g. CH 4 ) to 900-1200‹ C. to add carbon thereto and then cooling. The corresponding carbides may be formed by heating rapidly to 1300-2000‹ C. for a short time in an inert or reducing atmosphere. In forming the filaments of the invention the glass-forming oxide is preferably introduced in an alkali solution of the cellulose compound as a soluble compound, e.g. silicate, aluminate or borate. Insoluble hydroxide forming elements such as Zr may be introduced as a water-soluble Zr salt, e.g. Zr(SO 4 ) 2 by the injection spinning method.
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