A yarn is described comprising a sheath of individually wrapped aramid fibres surrounding, and virtually covering, a continuous filament core of amorphous silica product (>96% silica) possessing the thermal performance of a refractory material. Moulded fiber reinforced plastics articles Radvan, B. and Skelding, W. T. H. (The Wiggins Teape Group Limited, Basingstoke, England) US Pat 4 670 331 (2 June 1987) In this method, a sheet of thermoplastics material, consolidated tinder heat and pressure and containing 20-70 weight % flexurally stressed glass reinforcing fibres 7-50mm in length, is heated until mouldable, expanded and porous, and then moulded whilst retaining some of the porosity. An article of moulded fibre reinforced plastics material made by this method, is also claimed. Method for fastening aircraft frame elements to sandwich skin panels covering same using woven fiber connectors Jonas, P. J. (Beech Aircraft Corporation, Wit Wichita, KS, USA) US Pat 4 671 470 (9 June 1987) A method for joining aircraft sandwich skin panels comprising a core bounded inside and outside by inner and outer face sheets to a frame element longitudinally-extending is given. A claim is also made for a joint between such a skin panel and an elongate structural frame element. Gas turbine composite parts Galasso, F. S. and Veltri, R. D. (United Technologies Corporation, Hartford, CN, USA) US Pat 4 671 997 (9 June 1987) Improved resistance to oxidation at operation temperatures >2500°F is claimed with a silicon carbide coating of thickness 0.04-30mils bonded to the carbon-carbon composite with a chemical vapour deposition applied layer of silicon nitride (thickness 3-30mils) on the outer surface of the coating. Method for manufacture of fiber reinforced resin structure such as a steering wheel core member Yamazawa, Y., Kondo, K., Tsutiya, Y., Niimi, T., Yamamoto, T. and Matsuba, K. (Toyota Jidosha Kabushiki Kaisha, Toyota, Japan) US Pat 4 673 451 (16 June 1987) A long continuous resin impregnated fibre strand repeatedly wound around a moulded jig of predetermined structure is drawn out and wound into numerous extended loops at each branched portion of the structure. These loops, which are capable of being wrapped around the winding of fibres at the branched portions, are wound tightly around each of the branched portions and the resin is hardened. Load-introducing armature as component part of a laminated structural element (Unden, H. and Ridder, S.-O., both of Sweden) US Pat 4 673 606 (16 June 1987) Layers of fibre-reinforced plastic matrix are connected through holes in the partly embedded load-bearing armatures withpegs compatible with the matrix material, these pegs subject to shearing stress at both ends on the introduction of load to the structure via the armatures. Properties of composite laminates using leaky Lamb waves
COMPOSITES. MAY 1988
Chimenti, D. E. and Bar-Cohne, Y. (Secretary of the Air Force, Washington, DC, USA) US Pat 4 674 334 (23 June 1987) A system for detecting defects in the structure of a composite laminate material is described where Lamb waves are generated in the material via a first transducer directing an ultrasonic beam of preselected frequency along a transmission axis and a second transducer, receiving leaky Lamb waves reflected along a reflexion axis (intersecting with the transmission axis within the material at a given distance below the surface), outputs a signal corresponding to the amplitude of the waves. Double-lobe fuselage composite airplane Whitener, P. C. and Olason, R. (The Boeing Company, Seattle, WA, USA) US Pat 4 674 712 (23 June 1987) A wide-body composite material constructed airplane fuselage is described, the centrebody section of which comprises composite material panels of a honeycomb core with face sheets on both sides forming a contoured external shell of two horizontally adjacent lobes and a vertical plane bulk head, continuous hinge joints transmitting and redistributing structural loads from each of the face sheets through a common hinge axis holding the two parts together. Method for manufacturing a pipe part from fibre-reinforced thermosetting synthetic material Offringa, O. R. and van der Ploeg, F. (Wavin B. V., Zwolle, The Netherlands US Pat 4 675 965 (30 June 1987) Pre-formed pipe parts of fibre-reinforced thermosetting synthetic material are placed on part of a mandrel used to define the inside shape, partially covering it. Synthetic resin impregnated fibres are applied to the uncovered parts of the mandrel and to the adjacent parts of the pre-formed pipes, until the pipe part reaches the desired final shape. The pipe part is cured and the mandrel removed. Seamless laminar article Topolski, A. S. (E. I. Du Pont de Nemours and Company, Wilmington, DE, USA) US Pat 4 677 006 (30 June 1987) A laminar, moulded, hollow article is described comprising two imcompatible polymers components: the first in a continuous matrix phase; the second present as thin, two-dimensionaL parallel and overlapping layers of material, with knit lines curved to provide such overlapping layers in any radial section through a wall of the hollow article.
MATERIALS Carbon fibrils, method for producing same and compositions containing same Tennet, H. G. (Hyperion Catalysis International, Inc., Andover, MA, USA) US Pat 4 663 230 (5 May 1987) A cylindrical carbon fibril of diameter 3.5-7.0nm (length >102 diameter) with an outer region of many continuous layers of ordered carbon atoms and a distinct inner core, both positioned concentrically about the cylindrical axis of the fibril.
Flexible, chemically treated fibers and coated fabrics thereof Girgis, M. M. and Lawton, E. L. (PPG Industries, Inc., Pittsburgh, PA, USA) US Pat 4 663 231 (5 May 1987) The detailed composition of a chemical coating for flexible bundles of sized filaments is described. Friction materials and their manufacture Harding, J. D. and Dolbear, K. D. (Turner & Newall, PLC, Manchester, England) US Pat 4 663 368 (5 May 1987) A non-asbestos clutch facing comprising reinforcing fibres 4-60 weight % embedded in a binder material matrix, the facing being permeable to air under a pressure differential of 1 atmosphere with a density 72-90% of theoretical density. A method for manufacture is also claimed. Glass-fiber reinforced polypropylene resin composition Kawai, Y., Abe, M,, Maki, M. Suzuki, K. and Hoshino, M. (Mitsui Toatsu Chemicals, Inc., Tokyo, Japan) US Pat 4 663 369 (5 May 1987) The detailed composition of a glass-fibre reinforced polypropylene resin is described. Fiberized joint/crack sealant composition Marvel, St., J. B. and Modrak, J. P. (Hercules Incorporated, Wilmington, DE, USA) US Pat 4 663 370 (5 May 1987) The detailed composition of an asphalt paving and sealing material is given, comprising polyolefin or polyester reinforcing fibre, unsaturated fatty acid, aggregate and an adhesion control component. Composite material made from matrix metal reinforced with mixed crystalline aluminasilica fibers and mineral fibers Dohnomoto, T. and Kubo, M. (Toyota Jidosha Kabushiki Kaisha, Toyota, Japan) US Pat 4 664 704 (12 May 1987) The detailed composition for the title composite material is given, comprising >1 volume % of a hybrid fibre mixture as reinforcing material, and a matrix metal. Fire resistant gypsum composition Wilson, G. E. and Lehnert, C. W. (GeorgiaPacific Corporation, Stamford, CN, USA) US Pat 4 664 707 (12 May 1987) A core of fire-resistant gypsum board comprising the set product of >80 weight % calcined gypsum, >0.04 weight % glass fibres, >0.1 weight % whisker fibres and >1.5 weight % clay. Reinforced composites made by electrophoretically coating graphite or carbon Scala, L. C., Fuller, T. J. and AIvino, W. M. (Westinghouse Electric Corporation, Pittsburgh, PA, USA) US Pat 4 664 768 (12 May 1987) A flat mat of graphite or carbon is electrophoretically coated with an electrophoretable polymer. The polymer is partially cured, the flat mat is impregnated with thermosetting impregnating resin and B-staged to form a prepreg. The prepregs are stacked and the resin in the stack cured to the C-stage under heat and pressure. Aromatic polyamide fiber-based composite prepreg Ueno, S., Hoshida, S. and Nomura, H. (Shin-Etsu Chemical Co., Ltd., Tokyo,