Filament network for a composite structure

Patent metadata

Field	Value
Publication number	US-10632718-B2
Application number	US-201414501125-A
Country	US
Kind code	B2
Filing date	Sep 30, 2014
Priority date	Sep 30, 2014
Publication date	Apr 28, 2020
Grant date	Apr 28, 2020

Abstract

A filament network for a composite structure may include a number of fiber layers, wherein each fiber layer includes a fiber bundle and a filament layer at least partially covering the fiber bundle, the filament layer including discontinuous filaments including at least one of different length filaments including first length filaments and second length filaments, wherein the first length filaments include a first length and the second length filaments include a second length, and wherein the first length is different than the second length and different type filaments including first type filaments and second type filaments, wherein the first type filaments include a first material composition, wherein the second type filaments include a second material composition, and wherein the first material composition is different that the second material composition, and a resin binding the number of fiber layers together.

First claim

What is claimed is:

1. A fiber layer comprising:
a pair of layers of reinforcement material, said reinforcement material comprising a plurality of fiber bundles of continuous reinforcing fibers; and
an interlayer disposed between and coupled to said pair of layers of said reinforcement material, said interlayer comprising a filament network comprising:
first discontinuous filaments, said first discontinuous filaments comprising a polymeric material having a first length between 15 micrometers and 15 millimeters and a melting temperature between 50° C. and 175° C.;
second discontinuous filaments entangled with said first discontinuous filaments, said second discontinuous filaments comprising a stiff material having a second length between 30 millimeters and 100 millimeters and a melting temperature greater than 175° C.; and
third discontinuous filaments entangled with said first discontinuous filaments and said second discontinuous filaments, said third discontinuous filaments comprising a functional material having a third length between 15 millimeters and 30 millimeters and a melting temperature greater than 175° C.; and wherein:

said first discontinuous filaments and said third discontinuous filaments are positioned so that filament ends of a portion of said first discontinuous filaments and a portion of said third discontinuous filaments at least partially penetrate said plurality of fiber bundles of said pair of layers of said reinforcement material;
said first discontinuous filaments provide for thermal bonding of said filament network and said pair of layers of said reinforcement material when melted;
said second discontinuous filaments provide for mechanical strength and stability of said fiber layer; and
said functional material of said third discontinuous filaments imparts at least one functional characteristic to said fiber layer.

2. The fiber layer of claim 1 wherein said filament network comprises 25 percent by weight of said first discontinuous filaments, 50 percent by weight of said second discontinuous filaments, and 25 percent by weight of said third discontinuous filaments.

3. The fiber layer of claim 1 wherein said at least one functional characteristic comprises toughness, stiffness, flame resistance, surface area, and conductivity.

4. The fiber layer of claim 1 wherein said filament network further comprises continuous filaments, and wherein said first discontinuous filaments, said second discontinuous filaments, said third discontinuous filaments, and said continuous filaments are entangled together within said filament network.

5. The fiber layer of claim 1 wherein:
said filament network further comprises a permeable film;
said first discontinuous filaments, said second discontinuous filaments, and said third discontinuous filaments are dispersed in said film; and
said film is arranged between said pair of layers of said reinforcement material so that said filament ends of said first discontinuous filaments and said third discontinuous filaments at least partially penetrate said plurality of fiber bundles of said pair of layers of said reinforcement material.

6. The fiber layer of claim 1 further comprising a resin infused through said interlayer, comprising said filament network, and said pair of layers of said reinforcement material, wherein said resin permeates entirely through said interlayer, comprising said filament network, and said pair of layers of said reinforcement material.

7. The fiber layer of claim 1 wherein said filament network further comprises a binder to bind said first discontinuous filaments, said second discontinuous filaments, and said third discontinuous filaments together.

8. The fiber layer of claim 1 wherein said first discontinuous filaments cross over said second discontinuous filaments and said third discontinuous filaments cross over said second discontinuous filaments.

9. The fiber layer of claim 1 wherein said polymeric material of said first discontinuous filaments comprises at least one of polyolefin, polyurethane, and thermoplastic.

10. The fiber layer of claim 1 wherein said stiff material of said second discontinuous filaments comprises at least one of carbon, glass, metal, and ceramic.

11. The fiber layer of claim 1 wherein:
said functional material of said third discontinuous filaments comprises at least one of carbon, polyether ether ketone, polyimide, nylon, and polyurethane; and
said at least one functional characteristic comprises toughness.

12. The fiber layer of claim 1 wherein:
said functional material of said third discontinuous filaments comprises at least one of polyimide, polybenzoxazole, polybenzimidazole, polybenzthiazole, polybenzoxazine, ceramic, and glass; and
said functional characteristic comprises flame resistance.

13. The fiber layer of claim 1 wherein:
said functional material of said third discontinuous filaments comprises at least one of carbon and metal; and
said functional characteristic comprises electrical conductivity.

14. The fiber layer of claim 1 wherein said filament network comprises a thickness of between 0.1 microns and 50 microns.

15. The fiber layer of claim 1 wherein:
said functional material of said third discontinuous filaments comprise a first type and a second type, different than said first type;
said first type comprises a first material composition imparting a first functional characteristic to said fiber layer; and
said second type comprises a second material composition, different than said first material composition, imparting a second functional characteristic, different than said first functional characteristic, to said fiber layer.

16. The fiber layer of claim 15 wherein said functional material of said third discontinuous filaments further comprise a third type, different than said first type and said second type, and wherein said third type comprises a third material composition, different than said first material composition and said second material composition, imparting a third functional characteristic, different than said first functional characteristic and said second functional characteristic, to said fiber layer.

17. The fiber layer of claim 1 further comprising:
a plurality of layers of said filament network; and
a plurality of layers of said reinforcement material,
wherein said plurality of layers of said filament network and said plurality of layers of said reinforcement material are arranged in an alternating stacked configuration such that each one of said plurality of layers of said filament network forms an interlayer between adjacent ones of said plurality of layers of said reinforcement material.

18. The fiber layer of claim 17 wherein each one of said plurality of layers of said filament network comprises a thickness of between 0.1 microns and 50 microns.

19. The fiber layer of claim 7 further comprising a resin infused through said interlayer, comprising said filament network, and said pair of layers of said reinforcement material.

20. A reinforcement layup comprising:
a plurality of said fiber layers of claim 1 arranged in a stacked configuration; and
at least one interlayer disposed between adjacent fiber layers.

Assignees

• Boeing Co

Inventors

• Meure Sam
• Howe Christopher A
• Wilenski Mark S

Classifications

• B32B2605/18

  Aircraft · CPC title

• B29C70/08 Primary

  comprising combinations of different forms of fibrous reinforcements incorporated in matrix material, forming one or more layers, and with or without non-reinforced layers · CPC title

• B32B2260/046

  Synthetic resin · CPC title

• B29C70/12

  using fibres of short length, e.g. in the form of a mat {(non-woven fabrics per se D04H1/00)} · CPC title

• D04H13/00

  Other non-woven fabrics · CPC title