STRUCTURAL COMPONENT

Abstract

A structural component, in particular for an aircraft, spacecraft or rocket, has a ply of fiber reinforced polymer; a first carbon nanotube mat; and a metallic layer, wherein the carbon nanotube mat and the metallic layer are arranged on the ply of fiber reinforced polymer to form a hybrid lightning strike protection layer. A component for manufacturing such a structural component, a method for manufacturing a component of this type, a method for manufacturing a structural component and an aircraft or spacecraft with such a structural component are described.

Claims

1. A structural component for an aircraft, spacecraft or rocket, the structural component comprising: a ply of fiber reinforced polymer; a first carbon nanotube mat; and a metallic layer, wherein the carbon nanotube mat and the metallic layer are arranged on the ply of fiber reinforced polymer to form a hybrid lightning strike protection layer.

2. The component of claim 1, wherein the first carbon nanotube mat and the metallic layer are embedded in a matrix or in a matrix of the ply of fiber reinforced polymer.

3. The component of claim 1, wherein the first carbon nanotube mat and the metallic layer are embedded in a matrix of the ply of fiber reinforced polymer.

4. The component of claim 1, wherein the hybrid lightning strike protection layer comprises a second carbon nanotube mat, wherein the metallic layer is arranged between the first carbon nanotube mat and the second carbon nanotube mat.

5. The component of claim 4, wherein the first carbon nanotube mat is arranged on the ply of fiber reinforced polymer.

6. The component of claim 4, wherein a dielectric coating or paint is applied on the second carbon nanotube mat

7. The component of claim 1, wherein the metallic layer comprises copper.

8. The component of claim 1, wherein the metallic layer is configured as an expanded metallic foil.

9. The component of claim 1, wherein the metallic is configured as an expanded copper foil.

10. The component of claim 1, wherein the first carbon nanotube mat is configured as non-woven carbon nanotube mat.

11. A component for manufacturing a structural component, which comprises: a ply of fiber reinforced polymer; a first carbon nanotube mat; and a metallic layer, wherein the carbon nanotube mat and the metallic layer are arranged on the ply of fiber reinforced polymer to form a hybrid lightning strike protection layer, wherein the component for manufacturing the structural component comprises: a ply comprising fiber material; a metallic layer; and a first carbon nanotube mat, wherein the first carbon nanotube mat and the metallic layer are arranged on the ply.

12. The component of claim 11, wherein at least the first carbon nanotube mat is impregnated with a non-cured matrix.

13. A method for manufacturing a component for manufacturing a structural component, which comprises: a ply of fiber reinforced polymer; a first carbon nanotube mat; and a metallic layer, wherein the carbon nanotube mat and the metallic layer are arranged on the ply of fiber reinforced polymer to form a hybrid lightning strike protection layer, wherein the component for manufacturing the structural component comprises: a ply comprising fiber material; a metallic layer; and a first carbon nanotube mat, wherein the first carbon nanotube mat and the metallic layer are arranged on the ply; and wherein the method comprises: placing a metallic layer, in particular an expanded copper foil, and a first carbon nanotube mat on a ply comprising fiber material.

14. The method of claim 13, further comprising a step of impregnating at least the first carbon nanotube mat with a non-cured matrix.

15. The method of claim 13, wherein placing the metallic layer and the first carbon nanotube mat on the ply comprises: placing the first carbon nanotube mat on the ply; placing the metallic layer on the first carbon nanotube mat; and placing a second carbon nanotube mat on the metallic layer.

16. The method of claim 15, further comprising a step of coating the second carbon nanotube mat with a dielectric coating or paint.

17. A method for manufacturing a structural component comprising: a ply of fiber reinforced polymer; a first carbon nanotube mat; and a metallic layer, wherein the carbon nanotube mat and the metallic layer are arranged on the ply of fiber reinforced polymer to form a hybrid lightning strike protection layer; wherein the method comprises: curing the matrix of a component comprising: a ply comprising fiber material; and a metallic layer; a first carbon nanotube mat, wherein the first carbon nanotube mat and the metallic layer are arranged on the ply; wherein at least the first carbon nanotube mat is impregnated with a non-cured matrix; or manufactured according to a method comprising: placing a metallic layer, in particular an expanded copper foil, and a first carbon nanotube mat on a ply comprising fiber material such that at least the first carbon nanotube mat and the metallic component are embedded in the cured matrix.

18. The method of claim 17, wherein the first carbon nanotube mat, the metallic layer and the ply are impregnated with the matrix together.

19. The method of claim 17, wherein the first carbon nanotube mat, the metallic layer and the ply are embedded together in the cured matrix.

20. An aircraft, spacecraft or rocket comprising a structural component comprising a ply of fiber reinforced polymer, a first carbon nanotube mat, and a metallic layer, wherein the carbon nanotube mat and the metallic layer are arranged on the ply of fiber reinforced polymer to form a hybrid lightning strike protection layer and/or manufactured according to a method comprising curing the matrix of a component comprising a ply comprising fiber material, a metallic layer, a first carbon nanotube mat, wherein the first carbon nanotube mat and the metallic layer are arranged on the ply, wherein at least the first carbon nanotube mat is impregnated with a non-cured matrix.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The accompanying drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this specification. The drawings illustrate the embodiments of the present disclosure and together with the description serve to explain the principles of the disclosure herein. Other embodiments of the present disclosure and many of the intended advantages of the present disclosure will be readily appreciated as they become better understood by reference to the following detailed description. The elements of the drawings are not necessarily to scale relative to each other. In the figures, like reference numerals denote like or functionally like components, unless indicated otherwise.

[0048] It will be appreciated that common and/or well understood elements that may be useful or necessary in a commercially feasible embodiment are not necessarily depicted in order to facilitate a more abstracted view of the embodiments. It will further be appreciated that certain actions and/or steps in an embodiment of a method may be described or depicted in a particular order of occurrences while those skilled in the art will understand that such specificity with respect to sequence is not actually required. It will also be understood that the terms and expressions used in the present specification have the ordinary meaning as is accorded to such terms and expressions with respect to their corresponding respective areas of inquiry and study, except where specific meanings have otherwise been set forth herein.

[0049] FIG. 1 schematically illustrates an exemplary sectional view of lightning strike protection measures of an airframe component.

[0050] FIG. 2 shows a schematic sectional view of a structural component.

[0051] FIG. 3 shows a schematic sectional view of a prepreg component.

[0052] FIG. 4 shows a front view of an exemplary aircraft.

[0053] Although specific embodiments are illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations may be substituted for the specific embodiments shown and described without departing from the scope of the present disclosure. Generally, this application is intended to cover any adaptations or variations of the specific embodiments discussed herein.

DETAILED DESCRIPTION

[0054] FIG. 1 schematically illustrates a sectional view of lightning strike protection of an airframe component.

[0055] In FIG. 1, reference sign 102 denotes a lightning strike protection layer placed on the top of a composite structure 100. The lightning strike protection layer 102 comprises e.g. an expanded copper foil 101 placed on the top of the composite laminate 103 but underneath protective dielectric coatings (e.g. paint layers) 104.

[0056] A veil 105 (combined with an epoxy resin surfacing film) is placed on the top of ECF 101 in order to decrease the surface roughness and to prepare the surface for the final varnish that is for example made up of several layers, as shown in FIG. 1.

[0057] FIG. 2 shows a schematic sectional view of a structural component 1.

[0058] The structural component 1 comprises a ply 2 of fiber reinforced polymer material, which comprises a matrix 8 and a plurality of carbon fibers 9. The structural component e. g. forms a carbon fiber reinforced polymer or carbon fiber reinforced plastic (CFRP) fuselage component of the skin 11 of an aircraft 10. The ply 2 of fiber reinforced polymer material thereby forms the structural basis of the structural component 1.

[0059] It is to be understood that FIG. 2 schematically shows the arrangement of layers of the structural component at an outer side, which may form the outer skin of an aircraft at any section thereof.

[0060] On the outer side of the ply 2 of fiber reinforced polymer, a hybrid lightning strike protection (LSP) layer 5 is arranged. The hybrid LSP layer 5 comprises first and second non-woven carbon nanotube mats (CNT-M) 3, 6 and a metallic layer 4 configured as expanded copper foil (ECF).

[0061] Carbon nanotubes (CNT) generally are cylindrical shaped carbon forms with nanometric diameters. In particular, they have a hollow structure with walls made of graphite or of graphene (a hexagonal structure made of carbon atoms).

[0062] Non-woven carbon nanotube mats (CNT-M) can be manufactured e. g. by way of a gas-phase catalytic reaction creating a dense cloud of very long carbon nanotubes. These can be collected, for example spun around a drum, to create a non-woven mat. Such non-woven carbon nanotube mats are manufactured e.g. by Tortech Nano fibers Ltd., Israel or Nanocomp Technologies Inc., USA.

[0063] An expanded copper foil (ECF) may be made from a continuous expansion of copper, e. g. by rolling. It can be provided with different surface weights, depending on the number and thickness of CNT-M in the hybrid lightning strike protection layer 5.

[0064] In the embodiment of FIG. 2, the first CNT-M 3 is arranged on the ply 2 of CFRP. Furthermore, a metallic layer 4 and a second carbon nanotube mat 6 are arranged on the first carbon nanotube mat 3. Accordingly, the metallic layer 4 is sandwiched between the first and second carbon nanotube mats 3, 6.

[0065] The first and second carbon nanotube mats 3, 6 and the metallic layer 4 there between are completely embedded in the cured matrix 8 of the ply 2 of fiber reinforced polymer material. Therefore, the hybrid LSP layer is firmly bonded to the CFRP-ply 2 in an integrated way.

[0066] Additionally, the structural component 1 is covered with a dielectric coating 7, which is arranged directly on the outer side of the second carbon nanotube mat 6.

[0067] FIG. 3 shows a sectional view of a prepreg component.

[0068] The prepreg component is a component 1′ for manufacturing a structural component 1 according to FIG. 2 by curing. Therefore, the prepreg component 1′ comprises a ply 2′ comprising a fiber material. The first carbon nanotube mat 3, the metallic layer 4 and the second carbon nanotube mat 6 are arranged on the ply in the order as described with reference to FIG. 2. However, the dielectric layer is not yet applied.

[0069] The ply 2′, the first carbon nanotube mat 3, the metallic layer 4 and the second carbon nanotube mat 6 are impregnated with a non-cured matrix 8′.

[0070] For manufacturing the prepreg component, the first carbon nanotube mat 3 is placed on the ply 2′. Further, the metallic layer 4 is placed on the first carbon nanotube mat 3 and the second carbon nanotube mat 6 is placed on the metallic layer 4. The complete component is then impregnated with a non-cured matrix 8′, which is e. g. a duroplastic/thermoset resin. This means, the ply 2′, the first carbon nanotube mat 3, the metallic layer 4 and the second carbon nanotube mat 6 are all impregnated with the non-cured matrix 8′ together to form the prepreg component 1′.

[0071] For manufacturing a structural component 1 according to FIG. 2, the matrix 8′ of the prepreg component 1′ is cured such that the ply comprising fiber material, the first carbon nanotube mat 3, the metallic component 4 and the second carbon nanotube mat are embedded in the cured matrix 8 and thus firmly bonded with each other.

[0072] Finally, the outer side of the second carbon nanotube mat 6 is coated with a dielectric coating 7.

[0073] FIG. 4 shows a front view of an exemplary aircraft 10. The aircraft 10 comprises a skin 11, part of which is formed as a structural component 1 according FIG. 2.

[0074] Accordingly, the aircraft (10) comprises a hybrid lightning strike protection (LSP) measure comprising an expanded copper foil (ECF) and a CNT non-woven mat (CNT-M).

[0075] Although specific embodiments of the disclosure herein are illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and/or equivalent implementations exist. It should be appreciated that the exemplary embodiment or exemplary embodiments are examples only and are not intended to limit the scope, applicability, or configuration in any way. Rather, the foregoing summary and detailed description will provide those skilled in the art with a convenient road map for implementing at least one exemplary embodiment, it being understood that various changes may be made in the function and arrangement of elements described in an exemplary embodiment without departing from the scope as set forth in the appended claims and their legal equivalents. Generally, this application is intended to cover any adaptations or variations of the specific embodiments discussed herein.

[0076] For example, it is not ultimately necessary to provide a second CNT non-woven mat. The hybrid lightning strike protection layer generally may also work with one CNT-M only, depending on the layout thereof. Accordingly, the CNT-M or even a plurality of CNT-M can be placed either underneath or on top of the metallic layer or ECF.

[0077] Additionally, the metallic layer does not necessarily have to consist of or comprise an ECF, but may have either alternative or additional other elements. In particular, the disclosure herein also covers other metals or alloys, e. g. nickel, aluminum, iron, brass, bronze or the like. For special applications, the metallic layer may comprise a metal or metal alloy with high conductivity comprising precious metal, such as e. g. silver. Furthermore, other kinds of layers then an expanded foil, e.g. an electrolytic foil, a grid (e. g. a wire grid or a stamped grid), or the like may be used.

[0078] Furthermore, the method for manufacturing the component or the structural component does not necessarily have to comprise a step of impregnation of the ply comprising fiber material. The ply may also be provided as already cured ply, e. g. of CFRP or GFRP, and only the hybrid lightning strike protection layer, meaning at least the first CNT-M and the metallic layer, are firmly bonded thereto, e. g. by impregnation and curing.

[0079] It will also be appreciated that in this document the terms “comprise”, “comprising”, “include”, “including”, “contain”, “containing”, “have”, “having”, and any variations thereof, are intended to be understood in an inclusive (i.e. non-exclusive) sense, such that the process, method, device, apparatus or system described herein is not limited to those features or parts or elements or steps recited but may include other elements, features, parts or steps not expressly listed or inherent to such process, method, article, or apparatus. Furthermore, the terms “a” and “an” used herein are intended to be understood as meaning one or more unless explicitly stated otherwise. Moreover, the terms “first”, “second”, “third”, etc. are used merely as labels, and are not intended to impose numerical requirements on or to establish a certain ranking of importance of their objects.

[0080] While at least one exemplary embodiment of the present invention(s) is disclosed herein, it should be understood that modifications, substitutions and alternatives may be apparent to one of ordinary skill in the art and can be made without departing from the scope of this disclosure. This disclosure is intended to cover any adaptations or variations of the exemplary embodiment(s). Furthermore, characteristics or steps which have been described may also be used in combination with other characteristics or steps and in any order unless the disclosure or context suggests otherwise. This disclosure hereby incorporates by reference the complete disclosure of any patent or application from which it claims benefit or priority.