Process for the manufacture of carbon fibre
(Compagnie, Francaise Thomson Houston-Hotchkiss Brandt) UK Patent
Jenkins, G. M. and Kawamura, K. (Coal Industry, Patents, Ltd) UK
Patent Specification, 1,228,91~) (21 April 1971)
By incorporating both very short and very long filaments in a matrix, a composite can give high breakage strength, a high modulus of elasticity and good resistance to notch cracking. Proportions by volume should be 80% matrix, 15% long filaments and 5% short fibres. Suggested materials are aluminium and thermoplastic resins for the matrix, stainless steel and silicon carbide for the long filaments and glass fibres for the short. Fabrication technique and orientation of the fibres is discussed.
Phenol and hexamine are mixed together at a temperature of 100°C to 200°C, phenol comprising 80% to 95% by weight of the mixture. The hexamine is decomposed and subsquent spinning of the mixture to form a fibre provides a precursor for the production of carbon fibre. Carbonization is carried out in an inert atmosphere. Details of the carbonization programme are given. Fibre diameter is found to relate to the strength and modulus of elasticity of these fibres.
posite is presented, to allow weight saving to be effected in structural members. The fibre reinforced component is clamped to the metal member, and is bonded to it by the application of heat, thus curing the pre-preg sheet with the resin itself acting as the bonding agent. A similar coefficient of thermal expansion must be shared by the components to prevent stressing and delamination.
A moulding of composite materials containing metal fibres and a process for it~ production
Hendrix, H. and Kilimann, G. (Glanzstoff A.G.) UK Patent Specifica-
tion, 1,930,938 (28 April 1971) A reinforced plastic bearing
(Plas-Steel Product, Inc) UK Patent
Specification, 1,228,503 1971)
A bearing is described giving low friction, good wear and dimensional stability characteristics. An annular core of glass fibre reinforced plastic is covered with a layer of polytetrafluoroethylene fibres and particles secured in a resin matrix. A method is also described for the production of resin impregnated polytetrafluoroethylene-cotton threads in the form of a bundle as bearing material. By winding the bundle on to a helical mandrel and curing and cutting the bundle in this configuration, a number of bearings can be made in one operation.
Reinforced carbon and graphite articles
(The Carborundum Co) UK Patent
Carbon fibres are coated with a refractory material, usually silicon carbide, before their incorporation in a carbon matrix. A great increase in the strength of the bond between matrix and coated fibres is produced. In these composites, clean breaks occur rather than interlaminar cracking and delamination failures in overstressed conditions. Improved resistance to high temperature and improved chemical resistance is also due to the refractory coating.
A cement mortar displays exceptional strength properties when reinforced with metal fibres. The fibres are steel coated with brass and are 5-15 mm long and constitute 2"5-10% by weight of the mortar mix. Helical wire elements, which tend to tangle and are difficult to distribute uniformly in the matrix, cannot compete with the small metal fibres which are simply stirred into the mortar. A table of flexural strength and compressive strength increases is given,
Improvements in or relating to apparatus for making composite filamentary structures
(Hercules Inc) UK Patent Specificatzon, 1,230,506 (5 May 1971) Improvement in composite materials
(Courtaulds Ltd) UK Patent Specifica-
Improvements relating to bodies of polyester resin/glass fibre composition
A composite of carbon fibres and thermoplastic resin is produced by laying together lengths of the carbon filaments and thermoplastic filaments or films. Under heat and pressure the materials coalesce together. Shredded thermoplastic film is best suited to this process. Orientation and lay-up of the components is variable and rod, sheet and block forms may be produced for machining.
Barley, R. P. and Clcments, D. A. (R. P. Barley Ltd) ' UK Patent
tion, 1,o28,573 (15 April 1971)
Improvements in processes and apparatus for the continuous production of fibrereinforced synthetic plastics material profiled bars
A surface treatment for polyesterresin/glass-fibre compogites sheet is described to enable nails to be driven mto the sheet. T o prevent the nail or tack from merely bending against the hard surface, an outer covering of granules of vermiculite and resin is provided. This carrier resin has thixotropic properties. The covering i.~ applied by a caulking gun to a thickness determined .by the length of the nails to be used. Application in the furniture industry is envisaged.
A tape of filamentary material is laid parallel to the previously laid tape by means of an automatic machine. T h e tape is fed under the drive wheel, while an edge-sensing device ensures that each pass of the machine is parallel. After the advance stroke the machine severs the tape, preparatory for the return stroke. T h e machine is designed to produce large scale contoured surfaces, with minimum gapping or over-laying of the tapes. Aircraft component manufacture Is the field of interest.
Filament reinforced tubular members
(Goldsworthy Engineering Inc) UK
Elsner, Lothar UK Patent Specifica-
Patent Specificatton, May 1971)
In the production of glass fibre reinforced plastics profiled bar, a synthetic thermosetting resin is deposited to form a gelled layer. The bar materials are wrapped within this layer and all are drawn through the forming tool. In this way the glass fibre material at the periphery of~he profiled bar is not laid bare by the scraping action of the die. A smooth finish-is ffbtained.
A machine is described for producing filament reinforced tube and pipe products, of both circular and noncircular cross-sections. Impregnated strands are passed to the winding stations, while the windin, g po eration may be altered for varying configurations and applications. T h e machine can be mounted upon a land vehicle or boat, the tube being laid at the rate ot production of the pipe.
tion, 1,298,684 (15 April 1971)
Process for the manufacture of articles made from a combination of metal and a fibre reinforced plastics composite
Molyneux, W. G. (Ministry of Aviation Supply) UK Patent Specifica-
tion, 1,299,90~ (98 April 1971)
A combination of metal member and carbon fibre reinforced plastics com-