Lightweight components

Abstract

A lightweight component in the form of an outlet guide vane 10 for a gas turbine engine. The vane 10 being filled with hollow metal ellipsoid members 12 in a solid metal outer 14.

Description

Embodiments of the present invention will now be described by way of example only and with reference to the accompanying drawings, in which:

FIG. 1 is a diagrammatic sectional view through a first aerofoil according to the invention;

FIG. 2 is a similar view of a second aerofoil according to the invention;

FIG. 3 is a diagrammatic sectional view through part of an aerofoil according to the invention;

FIG. 4 is a schematic perspective view of a sector panel in accordance with the invention;

FIG. 5 is a schematic perspective view of one stage in the manufacture of the sector panel of FIG. 4;

FIGS. 6( a), (b), (c) and (d) are schematic illustrations of a perfect ellipsoid and three possible distortions thereof; and

FIG. 7 is a schematic sectional view through a part of a lightweight component in accordance with the invention, in which the hollow bodies are themselves formed of a foamed material.

Claims

1. A component comprising a plurality of hollow members, in which at least most of the hollow members are spheroids or ellipsoids.

2. A component according to claim 1, and further comprising an outer surface member defining the shape of the component.

3. A component according to claim 2, in which the outer surface member comprises a wall or shell.

4. A component according to claim 2, in which the outer surface member is formed from a matrix material moulded around the hollow members.

5. A component according to claim 2, in which the hollow members are contained within the surface member but are not joined to one another.

6. A component according to claim 1, in which the hollow members are joined to one another.

7. A component according to claim 6, in which the hollow members are joined to one another by a matrix material.

8. A component according to claim 6, in which the hollow members are sintered together.

9. A component for a gas turbine engine, the component including a solid metal wall defining a hollow interior containing a plurality of hollow metal members, at least most of which members are spheroids or ellipsoids.

10. An aerofoil comprising a leading edge, a trailing edge, a concave pressure surface extending from the leading edge to the trailing edge and a convex suction surface extending from the leading edge to the trailing edge, the concave pressure surface and the convex suction surface being defined by an integral solid metal wall and defining a hollow interior, wherein the hollow interior of the metal aerofoil contains a plurality of hollow metal members, at least most of which members are spheroids or ellipsoids.

11. A component according to claim 1, in which the component is a containment casing or a containment casing liner for a gas turbine engine.

12. A component according to claim 1, in which all of the hollow members are spheroids or ellipsoids.

13. A component according to claim 1, in which the hollow members are made of a foam.

14. A component according to claim 1, in which the hollow members together form a foam.

15. A component according to claim 1, in which the hollow members are arranged to maximise a predetermined mechanical property of the component in a predetermined direction.

16. A component according to claim 15, in which the predetermined mechanical property is crushing strength or stiffness.

17. A component according to claim 1, in which the hollow members are arranged to minimise a predetermined mechanical property of the component in a predetermined direction.

18. A component according to claim 1, in which the length of the major axis of the hollow members is between 10 μm and 10000 μm.

19. A component according to claim 1, in which the length of the major axis of the hollow members is between 30 μm and 2000 μm.

20. A component according to claim 1, in which the portion of the component that consists of hollow members has a density of less than 3 g/cm3.

21. A component according to claim 1, in which the portion of the component that consists of hollow members has a density of less than 1 g/cm3.

22. A component according to claim 1, in which the minimum dimension of at least part of the hollow interior is smaller than the diameter of a sphere having the same volume as the hollow members.

23. A method of manufacturing a component, the method comprising the steps of placing a plurality of hollow members, at least most of which members are spheroids or ellipsoids, in a shaped mould, and joining the hollow metal members in the mould to form a component.

24. A method according to claim 23, in which a matrix material is poured into the mould around the hollow members.

25. A method of manufacturing a component, the method comprising forming a metal foam preform by bonding together hollow metal members, at least most of which members are spheroids or ellipsoids, forming a hollow metal outer, locating the preform in the outer, and bonding the preform thereto.

26. A method according to claim 25, in which the foam preform is bonded to the outer by diffusion bonding, brazing, adhesive bonding or welding.

27. A method according to claim 25, in which the metal foam is produced by bonding the hollow metal members together using a syntactic foam.

28. A method according to claim 25, in which the metal foam is produced by sintering the hollow metal members, with a mixture of metal powder and a space holder, and then burning out the space holder.

29. A method according to claim 28, in which the sintering takes place in a vacuum or an inert atmosphere.

30. A method according to claim 23, in which the component is for a gas turbine engine.

31. A method according to claim 30, in which the component is an aerofoil.