| 摘要 |
1,272,651. Composite material. UNITED KINGDOM ATOMIC ENERGY AUTHORITY. 1 May, 1969 [16 May, 1968; 2 Oct., 1968], Nos. 23461/68 and 46876/68. Heading C1M. A composite material comprises glass reinforced with carbon fibres produced by controlled thermal degradation and oxidation of organic fibres. The fibres preferably are produced from polyacrylonitrile, and preferably comprise 10- 70% by volume of the material. They may be short (e.g. 0À5-10 mm.) or in long lengths, and may be randomly oriented or aligned. The glass may be a borosilicate or soda-lime-silica glass, or a devitrified glass (e.g. an aluminosilicate). Examples of suitable glasses are given. The fibres may be incorporated in the molten glass, e.g. by casting, moulding, rolling or extruding, or mixed with the powdered glass and consolidated by hot pressing, preferably under vacuum. The latter method is used particularly with powdered devitrified glass. Alternatively the glass may be devitrified after forming the composite. Carbon fibres may be coated with powdered glass in suspension (e.g. in isopropyl alcohol or methyl ethyl ketone) with a binder present (e.g. polyvinylacetate or acrylic epoxy resin), and vacuum hot-pressed at, e.g. 800‹ C. Carbon fibres may also be coated with glass by electrophoresis from a suspension in methanol or with a ceramic oxide or metal. The composite may be made as a sheet, a plurality of these being pressed to form a bulk composite. |
