초록 ▼

An article such as a fan blade of a turbofan engine comprises a core made up of components at least some of which comprise packs of rods embedded in a resin matrix material. The rods extend in the span-wise direction of the blade to resist centrifugal forces imposed on the blade during operation. Th

An article such as a fan blade of a turbofan engine comprises a core made up of components at least some of which comprise packs of rods embedded in a resin matrix material. The rods extend in the span-wise direction of the blade to resist centrifugal forces imposed on the blade during operation. The core is encased in a skin formed from preforms which may comprise fabric reinforcements.

대표청구항 ▼

1. An article formed from a composite material, the article comprising adjacent core components with a web disposed between the core components, wherein at least one of the core components comprises a pack of reinforcement rods disposed parallel to each other and embedded in a resin matrix, each rod

1. An article formed from a composite material, the article comprising adjacent core components with a web disposed between the core components, wherein at least one of the core components comprises a pack of reinforcement rods disposed parallel to each other and embedded in a resin matrix, each rod comprising a resin-bonded bundle of reinforcement fibres. 2. An article as claimed in claim 1, in which the rods each have a circular cross-section. 3. An article as claimed in claim 1, in which the cross-section of each rod has a transverse dimension which is not less than 1.5 mm and not more than 3.5 mm. 4. An article as claimed in claim 1 in which the reinforcement fibres comprise carbon fibres. 5. An article as claimed in claim 1, in which the resin matrix comprises a cured syntactic material. 6. An article as claimed in claim 1, in which the resin matrix comprises an adhesive composition. 7. An article as claimed in claim 1, in which the resin matrix comprises a composite moulding compound. 8. An article as claimed in claim 1, in which the pack is one of a plurality of packs forming the article. 9. An article as claimed in claim 1, in which the or each pack comprises not less than 100 of the reinforcement rods. 10. An article as claimed in claim 1, in which the or each pack is overwrapped by braiding or reinforcement fabric. 11. An article as claimed in claim 1, in which each reinforcement rod is provided with an overwinding of reinforcing fibres in a resin matrix. 12. An article as claimed in claim 1, in which each reinforcing rod comprises a main body having a spacing projection for spacing the main bodies of adjacent rods from one another. 13. An article as claimed in claim 12, in which the spacing projection is of spiral form about a longitudinal axis of the respective rod. 14. An article as claimed in claim 1, in which the reinforcing rods extend substantially parallel to a lengthwise direction of the article. 15. An article as claimed in claim 1, in which the pack constitutes a core of the article which is provided with an outer layer enclosing the core. 16. An article as claimed in claim 15, in which the outer layer comprises reinforcement fibres in a resin matrix. 17. An article as claimed in claim 16, in which the reinforcement fibres are disposed in fabric layers. 18. An article as claimed in claim 17, in which each of the fabric layers comprises a multi-axial warp knit fabric. 19. An article as claimed in claim 18, in which the multi-axial warp knit fabric comprises fibres oriented at +45°/90°/−45° with respect to lengths of the rods. 20. An article as claimed in claim 19, in which the area weight of the fibres oriented at 90° varies in a lengthwise direction of the rods. 21. An article as claimed in claim 15, in which the outer layer comprises separate preforms applied to the core. 22. An article as claimed in claim 1, which is a component of a gas turbine engine. 23. An article as claimed in claim 22, in which the article is an aerofoil component. 24. An article as claimed in claim 23, which is a fan blade of a turbofan engine. 25. A method of manufacturing an article of composite material, the method comprising: assembling a plurality of reinforcement rods into a pack in which the rods are parallel to each other, each rod comprising a resin-bonded bundle of reinforcement fibres;impregnating the pack with at least one of a settable or curable first composition,at least one of causing or allowing the first composition to set or cure to form a resin matrix in which the rods of the pack are embedded;providing a fibre wrapping around the pack to form a core component;assembling a core of the article, the core including adjacent core components with a web disposed between the core components;assembling a fibre reinforcement over the core;placing the core with the assembled fibre reinforcement in a mould corresponding to the desired shape of the article;admitting at least one of a settable or curable second composition into the mould; andat least one of causing or allowing the second composition to set or cure to form the article. 26. A method as claimed in claim 25, in the assembling the fibre reinforcement comprises assembling preforms, each made up of reinforcing fabric layers over the core.