Dispersion strengthened metal composites Nadkarni, A., Samal, P.K. and Synk, J.E. (SCM Metal Products, Inc, Cleveland, OH, USA) US Pat 4 999 336 (12 March 1991) A substantially dense, unsintered powdered metal composite comprises a uniform dispersion of microparticles of refractory metal oxide in a metal or metal alloy matrix with discrete macroparticles of an additive material. High performance aramid matrix composites Croman, R.B., Ghorashi, H.M. and Singh, G. (E.I. Du Pont de Nemours and Company, Wilmington, DE, USA) US Pat 4 999 395 (12 March 1991) A copolyamide matrix is reinforced with 10 90 volume% ofaramid, carbon or glass fibres. 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 5 001 000 (19 March 1991) A composite sheet comprises a flexible thermoplastic polyarylate sheet with a glass transition temperature of > 145°C and a rigid layer of polyester resin polymerized with monomers that contains a filler pigment and glass fibres. The polyarylate sheet is 125 1000 pm thick and the polyester layer is 1500 7500 pm thick. Fibre reinforced plastics Tsuchiya, Y., Sekiyama, K., Kageyama, Y., Sakamoto, M., Sato, N., Sugiyama, M. and Kurauchi, T. (Kabushiki Kaisha Toyota Chuo Kenkyusho, Aichi and Toyota Jidosha Kabushiki Kaisha, Toyota, both of Japan) US Pat 5 001 172 (19 March 199l) A fibre-reinforced resin is described wherein the reinforcement consists of 30 50 volume% of 12.5 37.5 mm long chopped strands of assemblies of glass filaments and high modulus inorganic filaments. The assemblies consist of a maximum of 3000 fibres and contain 2 30 volume% of high modulus inorganic filaments. High modulus thermoplastic composites Barnes, J.A. and McNeil, D. (Imperial Chemical Industries pie, London, UK) US Pat 5 001 184 (19 March 1991) A composite comprises a thermoplastic matrix and at least 30 volume% of continuous, collimated, reinforcing filaments with at least 25 volume% being pitch-based graphitic filaments. The composite has a longitudinal flexural modulus of at least 210 GPa (measured according to ASTM D79081). Composite material reinforced by paraorientated aramide fibre sheet and process for preparing the same Toyoshima, S., Kouguchi, S. and Ibaraki, T. (Honshu Paper Co Ltd, Japan) US Pat 5 002 637 (26 March 199l) A composite is composed of a para-oriented aramide fibre sheet, a thermosetting resin matrix and a reactive siloxane oligomer at the fibre/matrix interface. The fibres are selected from poly(paraphenylene terephthalimide) and poly(paraphenylene 3, 4'-diphenylether terephthalimide) fibres.
Toughened prepregs and formulations Browne, J.M. and Kim, Y.S. (The Dexter Corporation, Pittsburgh, CA, USA) US Pat 5 002 821 (26 March 1991) A prepreg contains a fabric or unidirectionally aligned fibres and a thermosetting matrix resin of a mixed resin and a small amount of a chromium (Ill) complex.
OH, USA) US Pat 5 006 402 (9 April 1991) A composite is formed from 40 95 weight% of predominantly unidirectional, wholly aromatic polyester fibres and 5 60 weight% of partially crystalline, high performance thermoplastic polymer matrix with a melting point of at least 200°C. The fibres are formed in situ in the thermoplastic matrix.
Reinforced composites having improved flex fatigue life Chen, E.J.H. (E.I. Du Pont de Nemours and Company, Wilmington, DE, USA) US Pat 5 002 823 (26 March 1991) The composite has a polymeric matrix, 50 70 volume% of fibres and 1~7 weight% of polymeric fibre coating based on the weight of the fibres. The fibres are carbon, aramid or glass and are coated with polymer that has a modulus I 10 times greater than the matrix modulus and 10 120 times smaller than the fibre modulus.
Wholly aromatic polyester fibre-reinforced poly(phenylene oxide) and process for preparing same Isayev, A. (The University of Akron, Akron, OH, USA) US Pat 5 006 403 (9 April 1991) A composite comprises 2.5 95 weight% of predominantly unidirectional, wholly aromatic polyester fibres and 5 97.5 weight% of thermoplastic poly(phenylene oxide) matrix. The fibres are formed in situ in the thermoplastic matrix.
Fibrous reinforced materials impregnated with low viscosity polyurethanes/urea forming components Gillis, H.R. and Lin, I.S. (ICl Americas lnc, Wilmington, DE, USA) US Pat 5 002 830 (26 March 1991) A cured composite is made by impregnating a fibrous reinforcing material with a polyisocyanate component and an iminofunctional compound or enamine-containing compound. Fibre-reinforced metal matrix composites Dinwoodie, J., Taylor, M.D. and Stacey, M.H. (Imperial Chemical Industries pie, London, UK) US Pat 5 002 836 (26 March 1991) The composite is a metal matrix containing essentially aligned inorganic oxide fibres with a mean diameter of <5 pm. Any nonalignment provides for fibre intertwinement and thereby confers lateral cohesion on the product. Intermediate for composite of polymaleimide, polycyanate, epoxy resin and polyester Tada, H., lseki, T. and Agata, A. (Mitsubishi Rayon Co, Ltd, Tokyo, Japan) US Pat 5 003 013 (26 March 1991) An intermediate for a resin-impregnated reinforcing material is described which comprises: 100 parts by weight of a polyfunctional maleimide and a polyfunctional cyanate or an oligmer thereof (or a preliminary reaction product of these); 5 100 parts by weight of an epoxy compound; and 5 50 parts by weight of a polyester compound with a softening point of 20~100°C and a number average molecular weight of 500 10 000. Rigid polyethylene reinforced composites having improved short beam shear strength Kavesh, S., Kim, K., Kwon, Y.D. and Prevorsek, D.C. (Allied-Signal, Morris Township, Morris County, N J, USA) US Pat 5 006 390 (9 April 1991) A composite contains one or more layers, at least one of which is formed from a network of polyethylene filaments dispersed in a matrix. The polyethylene has a molecular weight of at least 150 000 and the filaments have an aspect ratio of less than 2.9:1. Wholly aromatic polyester fibre-reinforced high performance thermoplastic and process for preparing same Isayev, A. (The University of Akron, Akron,
3"70 C O M P O S I T E S . N U M B E R 4 . 1 9 9 3
Ternary metal matrix composite Jackson, M.B. and Roth, P.A. (Advanced Composite Materials Corporation, Greer, SC, USA) US Pat 5 006 417 (9 April 1991) The composite comprises a consolidated powder blend of 40 60 volume% of metallic binding matrix material; and a reinforcement comprising 10 50 volume% of insoluble ceramic and 10~,0 volume% of a semi-metal which may be of the same element as the ceramic. Fibre-reinforced rubber composition and production process and use thereof Takaki, T., Kaijiri, K., Oda, D., Oda, K., Kurihara, H. and Tanabe, T. (Ube Industries, Ltd, Yagamuchi, Japan) US Pat 5 006 603 (9 April 1991) The composition contains 100 parts by weight of an ethylene propylene~ficne copolymer and 2 100 parts by weight of fine, short, thermoplastic polyamide fibres. Based on the total weight of the above, also present are 0.2 5 parts by weight of a coupling agent. The coupling agent may be a silane or titanate coupling agent or it may be an unsaturated carboxylic acid, an anhydride or a mixture of these.
PROCESSES Ceramic composites reinforced with modified silicon carbide whiskers and method for modifying the whiskers Tiegs, T.N. and Lindemcr, T.B. (Martin Marietta Energy Systems Inc, Oak Ridge, TN, USA) US Pat 4 994 416 (19 FehruaO' 1991) The SiC whiskers arc subjected to a temperature of 800 1850°C and a combination of one or more of the following atmospheres: (I) an atmosphere at tess than atmospheric pressure; (2) an inert atmosphere of Ar, He, Ne or mixtures of these; (3) a gaseous atmosphere capable of reacting with metals or compounds on the surface or nearsurface regions of the whisker so that non-SiC materials on or near the surface of the whisker are reduced. The whiskers are homogeneously mixed with a ceramic powder and subjected to 28 70 MPa pressure and a temperature of 1600 1900°C to produce a composite with weak bonding between the whiskers and the matrix. Method for producing metal or alloy casting composites reinforced with fibrous or particulate materials