NANOTUBE-ENHANCED INTERLAYERS FOR COMPOSITE STRUCTURES

• US 20080286564A1
• Filed: 05/17/2007
• Published: 11/20/2008
• Est. Priority Date: 05/17/2007
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Tsotsis, Thomas K.
• Granted Patent: US 8,388,795 B2
• Time in Patent Office: Days
• US Class Current: 428/332
• CPC Class Codes: B29C 70/025 with particular filler
• CPC Class Codes: B29C 70/44 using isostatic pressure, e.g. pressure difference-moulding, vacuum bag-moulding, autoclave-moulding or expanding rubber-moulding
• CPC Class Codes: B29C 70/48 and impregnating the reinforcements in the closed mould, e.g. resin transfer moulding [RTM] , e.g. by vacuum
• CPC Class Codes: B29C 70/543 Fixing the position or configuration of fibrous reinforcements before or during moulding for non-woven fabrics D04H3/08
• CPC Class Codes: B29K 2105/167 Nanotubes
• CPC Class Codes: B32B 27/04 as impregnant, bonding, or embedding substance not used
• CPC Class Codes: B32B 5/26 another layer next to it also being fibrous or filamentary relative arrangement of fibres or filaments of different layers B32B5/12
• CPC Class Codes: B32B 5/28 impregnated with or embedded in a plastic substance not used
• CPC Class Codes: C09D 7/61 inorganic
• CPC Class Codes: C09D 7/70 characterised by shape, e.g. fibres, flakes or microspheres
• CPC Class Codes: Y10T 428/26 Web or sheet containing structurally defined element or component, the element or component having a specified physical dimension

Abstract

Carbon nanotube interlayer assemblies, methods of manufacturing carbon nanotube interlayer assemblies, and methods of manufacturing composite parts with carbon nanotube interlayer assemblies are disclosed herein. In one embodiment, a method of manufacturing a composite structure in accordance with an embodiment of the invention includes producing a plurality of carbon nanotubes on one or both sides of a substrate, and attaching the substrate to a first fiber layer. The method can further include positioning a second fiber layer adjacent to the first fiber layer to position the plurality of carbon nanotubes between the first and second fiber layers. The method can additionally include infusing the first and second fiber layers with resin, and curing the resin. In one embodiment, the carbon nanotube substrate can be attached to the first fiber layer by melt-bonding. In another embodiment, the carbon nanotube substrate can be attached to the first fiber layer with stitches.

Claims

1. A method of manufacturing a composite structure, the method comprising:

producing a plurality of carbon nanotubes on a substrate;

attaching the substrate to a first fiber layer;

positioning a second fiber layer adjacent to the first fiber layer to position the plurality of carbon nanotubes between the first fiber layer and the second fiber layer;

infusing the first and second fiber layers with resin; and

curing the resin to harden the composite structure.

2. The method of claim 1 wherein attaching the substrate to the first fiber layer includes bonding the substrate to the first fiber layer.

3. The method of claim 1 wherein the substrate includes a bond-layer, and wherein attaching the substrate to the first fiber layer includes heating the bond-layer and the first fiber layer to melt-bond the substrate to the first fiber layer.

4. The method of claim 1 wherein attaching the substrate to the first fiber layer includes mechanically fastening the substrate to the first fiber layer.

5. The method of claim 1 wherein attaching the substrate to the first fiber layer includes stitching the substrate to the first fiber layer with a thread.

6. The method of claim 1 wherein producing a plurality of carbon nanotubes on a substrate includes growing a plurality of carbon nanotubes on a flexible substrate.

7. The method of claim 1 wherein the substrate has a first side and a second side, and wherein producing a plurality of carbon nanotubes on the substrate includes producing a first portion of carbon nanotubes extending at least generally perpendicularly from the first side of the substrate, and producing a second portion of carbon nanotubes extending at least generally perpendicularly from the second side of the substrate.

8. The method of claim 1 wherein positioning the plurality of carbon nanotubes between the first fiber layer and the second fiber layer includes orienting the plurality of carbon nanotubes to extend at least generally perpendicular to the first and second fiber layers.

9. The method of claim 1 wherein infusing the substrate and the first and second fiber layers with resin includes preimpregnating the substrate and the first fiber layer with a first portion of resin, and preimpregnating the second fiber layer with a second portion of resin, before positioning the second fiber layer adjacent to the substrate.

10. The method of claim 1 wherein producing a plurality of carbon nanotubes on a substrate includes growing a first plurality of carbon nanotubes on a first flexible substrate, wherein attaching the substrate to the first fiber layer includes heating the first flexible substrate and the first fiber layer to melt-bond the first flexible substrate to the first fiber layer, and wherein the method further comprises

growing a second plurality of carbon nanotubes on a second flexible substrate;

heating the second flexible substrate and the second fiber layer to melt-bond the second flexible substrate to the second fiber layer; and

positioning a third fiber layer adjacent to the second fiber layer to position the second plurality of carbon nanotubes between the second fiber layer and the third fiber layer, wherein infusing the first and second fiber layers with resin includes infusing the first and second flexible substrates and the first, second, and third fiber layers with resin.

11. The method of claim 10, further comprising laminating additional carbon nanotube enhanced fiber layers onto the third fiber layer.

13. The method of claim 1 wherein the composite structure is a composite aircraft structure, and wherein the method further comprises assembling the hardened composite structure into a portion of an aircraft.

14. The method of claim 13 wherein growing a plurality of carbon nanotubes on a flexible substrate includes growing a plurality of carbon nanotubes on a transition metal catalyst with chemical vapor deposition, and wherein attaching the flexible substrate to a fiber layer includes heating the substrate and the fiber layer to melt at least a portion of the substrate and bond the carbon nanotubes to the fiber layer.

15. The method of claim 13 wherein the substrate has a first side and a second side, and wherein growing a plurality of carbon nanotubes on a flexible substrate includes producing a first portion of carbon nanotubes extending at least generally perpendicularly from the first side of the substrate, and producing a second portion of carbon nanotubes extending at least generally perpendicularly from the second side of the substrate.

16. The method of claim 13 wherein attaching the flexible substrate to a fiber layer includes coating the fiber layer with a generally even distribution of approximately perpendicular carbon nanotubes.

17. The method of claim 13, further comprising applying a bond layer to the flexible substrate, wherein attaching the flexible substrate to a fiber layer includes melting at least a portion the bond layer.

18. The method of claim 13 wherein growing a plurality of carbon nanotubes on a flexible substrate includes growing a first plurality of carbon nanotubes on a first side of the flexible substrate and growing a second plurality of carbon nanotubes on a second side of the flexible substrate, and wherein attaching the flexible substrate to a fiber layer includes stitching at least a portion the flexible substrate to the fiber layer.

13-1. A method of producing a carbon nanotube-enhanced interlayer assembly for composite structures, the method comprising:

growing a plurality of carbon nanotubes on a flexible substrate; and

attaching the flexible substrate to a fiber layer.

19. A composite structure comprising:

first fiber layer;

a second fiber layer;

an interlayer positioned between the first and second fiber layers, wherein the interlayer includes;

a substrate; and

a plurality of carbon nanotubes attached to the substrate, wherein the plurality of carbon nanotubes are at least generally perpendicular to the substrate; and

matrix material infused into the first and second fiber layers.

20. The composite structure of claim 19 wherein the plurality of carbon nanotubes is a first plurality of carbon nanotubes extending from a first side of the substrate, and wherein the interlayer further includes a second plurality of carbon nanotubes extending from a second side of the substrate.

21. The composite structure of claim 19 wherein the substrate is melt-bonded to the first fiber layer.

22. A system for manufacturing a composite structure, the system comprising:

means for producing a plurality of carbon nanotubes on a substrate;

means for attaching the substrate to a first fiber layer so that the plurality carbon nanotubes extend away from the first fiber layer; and

means for positioning a second fiber layer over the substrate to position the plurality of carbon nanotubes between the first fiber layer and the second fiber layer.

23. The method of claim 22, further comprising:

means for infusing the substrate and the first and second fiber layers with resin; and

means for curing the resin.