Fire-resisting material

fins extending laterally on opposite sides such that the ratio of maximum width to the thickness of the metal fibre is in the range 2.5 6. Ceramic composite and process for preparation thereof Kanai, T., Tanemoto, K., Kubo, H. and Sato, T. (Nippon Steel Corporation, Tokyo, Japan) US Pat 4 960 734 (2 October 1990) A sintered body with an average grain size of at least 1 lam comprises 20 95 weight % of hexagonal BN, 5 80 weight % of an A1N and any unavoidably formed A1ON, and 0.01 5 parts by weight (based on 100 parts by weight of the above phases) of a sintering aid or the reaction product of a sintering aid and any of the above. The body has a degree of thermal conductivity anisotropy of at least two, with the direction of maximum thermal conductivity being perpendicular to the direction of minimum thermal conductivity. Alumina-zirconia--silicon carbide--magnesia ceramics Mehrotra, P.K. and Billman, E.R. (Kennametal Inc, Latrobe, PA, USA) US Pat 4 960 735 (2 October 1990) An alumina matrix contains 1.5 32.5 volume % of silicon carbide and/or titanium carbide whiskers, 0.03 3 volume % of residual magnesia and 5 17.5 volume % of zirconia, with at least 2 volume % of the zirconia being tetragonal zirconia. Mullite-alumina composite sintered body and process for producing the same Hori, S. and Kurita, R. (Kureha Chemical Industry Co, Ltd, Tokyo, Japan) US Pat 4 960 738 (2 October 1990) The body contains mullite and alpha alumina with no glass phase and I% or less porosity. The average grain diameter is less than 1 lam and grains with a length of greater than 2.5 I-tm being 1% or less. The body comprises 77 85 weight % of alumina and the balance is silica. Aluminium composite material Kusui, J., Tanaka, A. and Kawai, M. (Toyo Aluminium Kabushiki Kaisha, Japan) US Pat 4 961 779 (9 October 1990) An aluminium composite contains artificially synthesized, amorphous carbon particles with a mean particle size of 1 50 ~tm. Fire-resisting material Grimwood, D.A. (Insumat Limited, London, UK) US Pat 4 961 989 (9 October 1990) A flame-resistant flexible sheet includes a layer of refractory ceramic fibres fully impregnated by and totally encapsulated by a fire-resistant silicone rubber compound. Fibrous material for composite materials, fibrereinforced composite materials produced therefrom, and process for producing same Yamada, S., Towata, S., Ikuno, H., Yamamura, T., lshikawa, T. and Shibuya, M. (Kabushiki Kaisha Toyota Chuo Kenkyusho and Ube Industries Ltd, both of Japan) US Pat 4 961 990 (9 October 1990) A fibrous material for a composite comprises a number of bundles of continuous ceramic, carbon or metal fibres in which fine particles and either short fibres or whiskers of a heatresistant ceramic, carbon or metal are in contact with the surfaces of the continuous fibres.

Reinforced bone cement, method of production thereof and reinforcing fibre bundles therefor Ducheyne, P., Topoleski, L D . T . and Cuckler, J.M. (Trustees of the University of Pennsylvania, Philadelphia, PA, USA) US Pat 4 963 151 (16 October 1990) Bundles of reinforcing fibres, each fibre having a diameter of 5 100 lam and a length of 0.5 10 mm, with the bundles having a length to diameter ratio of 10:1 to 1:10, are held together by an adhesive material soluble in the liquid monomer component of a twocomponent bone cement. The fibres are incorporated into the bone cement by the surgeon during a surgical operation.

PROCESSES Method of making composite sintered apex seal material Revankar, G.S. (Deere & Company, Moline, IL, USA) US Pat 4 954 058 (4 September 1990) A mixture of tungsten carbide particles and cobalt is sintered with a molybdenum, iron and cobalt alloy to form a wear-resistant body containing more non-angular tungsten carbide particles than it did before sintering. Production of thermoset composites containing thermoplastic fillers Turpin, R.L. (Lockheed Corporation, Calabasas, CA, USA) US Pat 4 954 195 (4 September 1990) 5 40 weight % of 10 80/am thermoplastic resin particles are uniformly dispersed in a thermosetting resin. The thermoplastic resin is insoluble in the thermosetting resin at room temperature and at pre-curing elevated temperatures, but is soluble under the curing conditions required for the thermosetting resin. Process for producing prepreg and laminated sheet Ohtake, T., Hayashi, M., Idemura, S., ()hi, K. and Kunitake, Y. (Dainippon Ink and Chemical, Inc, Tokyo, Japan) US Pat 4 954 304 (4 September 1990) A fibrous base is impregnated with a composition comprising a room temperature liquid epoxy resin, an epoxy resin curing agent, a resin containing a polymerizable unsaturated group, a room temperature liquid polymerizable vinyl monomer with 4 18 C atoms and a polymerizable initiator. Tile only solvent is the vinyl monomer which is removed after impregnation. Method of making matrix composites Pinkhasov, E. (Vapor Technologies Inc, Mt. Vernon, NY, USA) US Pat 4 955 135 (11 September 1990) Interstitial and external walls of a synthetic resin foam material are coated with a heatresistant material which forms a continuous network. The resin is pyrolysed to leave a porous structure into which a second phase is deposited, thus filling the pores. The whole is compacted to form the composite. Method of forming a joint between a connecting piece and a product formed of composite material, said joint, and said connecting piece for forming said joint Kivi, 1., Manner, T., Kuvaja, K. and Terfiv/i, J. (Exel Oy and Rauma-Repola Oy, Finland) US Pat 4 955 970 (11 September 1990~

A shouldered connecting piece is placed in the region where the component is being formed. Reinforcing fibres from the composite are extended round the shoulder with some crossing themselves in this region. The resulting joint is self-tightening and the joint and the product are formed simultaneously. Porous ceramic composite with dense surface Dwivedi, R.K. (Lanxide Technology Company, LP, Newark, DE, USA) US Pat 4 956 137 (11 September 1990) A method of forming a ceramic composite article comprises heating a preform of filler material and parent metal, wherein the oxidation reaction product of all the parent metal exceeds the total spatial volume in the preform, in the presence of an oxidant such that the parent metal melts and reacts to form an oxidation reaction product. The molten metal is transported towards the oxidant through the oxidation reaction product, thereby filling the total spatial volume but leaving voids where the metal was originally situated. The reaction is allowed to continue until a dense, void-free layer of oxidation reaction product is formed on at least one surface. Method for forming complex oxidation reaction products including superconducting articles Rapp, R.A., Urquhart, A.W., Nagelberg, A.S. and Newkirk, M.S. (Lanxide Technology Company, LP, Newark, DE, USA) US Pat 4 956 338 (11 September 1990) A parent metal source comprising at least one first metal is positioned next to a permeable mass comprising at least one metal-containing compound. The parent metal is heated in the presence of a vapour phase oxidant to a temperature above its melting point such so that infiltration of the preform and oxidation of the parent metal can occur, without reduction of the metal-containing compound in the filler, to form a complex oxidation reaction product containing two or more metals in the oxidized state. Method for producing a protective layer on a ceramic body lrick, V., Kuszyk, J.A. and Landini, D.J. (Lanxide Technology Company, LP, Newark, DE, USA) US Pat 4 957 779 (18 September 1990) A method for producing a ceramic matrix composite comprises heating a parent metal which is adjacent to a permeable filler to a temperature above its melting point so that it reacts with an oxidant to form an oxidation reaction product within the filler. As the reaction proceeds, molten metal is drawn through the oxidation reaction product and filler. On completion of the reaction the resultant composite is exposed to an cnvironment containing glassy particles which causes the growth of a protective layer on at least a portion of the composite. Process for forming a composite structure of thermoplastic polymer and sheet moulding compound Rohrbacher, F., Spain, P.L. and Fahlsing, R.A. (E.I. Du Pont de Nemours and Company, Wilmington, DE, USA) US Pat 4 959 189 (25 September 1990) A thermoplastic sheet is thermoformed into a three-dimensional structure and is placed into a mould with a corresponding shaped cavity along with a charge of thermosettable sheet

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