Thermoplastic sandwich structures

Patent metadata

Field	Value
Publication number	US-9358703-B2
Application number	US-201313937269-A
Country	US
Kind code	B2
Filing date	Jul 9, 2013
Priority date	Jul 9, 2013
Publication date	Jun 7, 2016
Grant date	Jun 7, 2016

Abstract

An apparatus and method are presented. An apparatus comprises a composite structure, a plurality of cavities extending into the composite structure, and a plurality of mandrels located within the plurality of cavities. The composite structure comprises a thermoplastic material that is consolidated. The plurality of mandrels comprises a first material that is configured to generate heat in response to a magnetic field.

First claim

What is claimed is:

1. An apparatus comprising:
a composite structure comprising:
a first layer of thermoplastic material;
a second layer of thermoplastic material; and
a core layer of thermoplastic material located between the first and second layer and comprising a plurality of cavities extending into the composite structure;

a metallic bladder located within the composite structure and configured to be pressurized to impart a compressive force on the composite structure; and
a plurality of mandrels located within the plurality of cavities, wherein the plurality of mandrels comprises a first material that is soluble and a second material that is configured to generate heat in response to a magnetic field.

2. The apparatus of claim 1 , wherein the composite structure is a sandwich structure and the plurality of mandrels are internal to the sandwich structure.

3. The apparatus of claim 2 , further comprising:
a tool, the tool comprising:
a plurality of dies creating a die cavity;
a number of die liners within the die cavity; and
a plurality of induction coils, sections of the plurality of induction coils embedded in the plurality of dies.

4. The apparatus of claim 1 , wherein the plurality of mandrels are within the thermoplastic core layer.

5. The apparatus of claim 4 , wherein the second material comprises a plurality of metallic tubes.

6. The apparatus of claim 1 , wherein the plurality of cavities extending into the composite structure are in communication with a plurality of openings in a surface of the composite structure.

7. The apparatus of claim 1 , wherein the second material comprises:
a plurality of tubes within the first material.

8. The apparatus of claim 1 , wherein the first and second thermoplastic layer are consolidated against the thermoplastic core layer.

9. An apparatus comprising:
a composite structure comprising a thermoplastic material that is consolidated, the thermoplastic material comprising:
a thermoplastic core layer comprising a plurality of cavities extending into the composite structure;
a first thermoplastic layer on a first side of the thermoplastic core layer, the first side of the thermoplastic core layer comprising an exterior surface of the thermoplastic core layer;
a second thermoplastic layer on a second side of the thermoplastic core layer, the second side of the thermoplastic core layer comprising an interior surface of the thermoplastic core layer;
a metallic bladder located within the composite structure, wherein the metallic bladder is configured to be pressurized to impart a compressive force on the composite structure;
a plurality of mandrels located within the plurality of cavities, wherein the plurality of mandrels comprises a first material that is soluble and a second material that is configured to generate heat in response to a magnetic field, the second material formed into a plurality of metallic tubes within the first material; and
a tool, the tool comprising:
a plurality of dies creating a die cavity;
a number of die liners within the die cavity; and
a plurality of induction coils, sections of the plurality of induction coils embedded in the plurality of dies.

10. An apparatus comprising:
a composite structure comprising:
a first layer of thermoplastic material;
a second layer of thermoplastic material; and
a core layer of thermoplastic material located between the first and second layer and comprising a plurality of cavities extending into the composite structure;

a metallic bladder located within the composite structure and configured to be pressurized to impart a compressive force on the composite structure;
a plurality of mandrels located within the plurality of cavities, wherein the plurality of mandrels comprises a first material that is soluble and a second material that is configured to generate heat in response to a magnetic field; and
a tool, the tool comprising:
a plurality of dies creating a die cavity;
a number of die liners within the die cavity; and
a plurality of induction coils, sections of the plurality of induction coils embedded in the plurality of dies.

11. A method of forming a consolidated structure comprising:
laying down a thermoplastic material to form a preform structure having a first layer of thermoplastic material, a second layer of thermoplastic material, and a core layer of thermoplastic material located between the first and second layer and comprising a plurality of cavities extending into the preform structure;
positioning a plurality of mandrels within the plurality of cavities, wherein the plurality of mandrels comprises a first material that is soluble and a second material that is configured to generate heat in response to a magnetic field;
positioning a metallic bladder within the preform structure, wherein the metallic bladder is configured to be pressurized to impart a compressive force on the preform structure; and
positioning the preform structure within a tool, the tool having a number of die liners configured to generate heat in response to a magnetic field.

12. The method of claim 11 , wherein laying down the thermoplastic material to form the preform structure having the plurality of cavities extending into the preform structure comprises:
laying down a braided thermoplastic material over the plurality of mandrels to form a plurality of core parts.

13. The method of claim 12 further comprising:
consolidating the preform structure to form the consolidated structure, consolidating comprising applying a magnetic field to the number of die liners to heat the preform structure to a consolidation temperature and wherein laying down the thermoplastic material to form the preform structure having the plurality of cavities further comprises laying down a braided thermoplastic material onto the metallic bladder to form the first layer of thermoplastic material, and placing the plurality of core parts over the first layer of thermoplastic material, and wherein consolidating the preform structure to form the consolidated structure further comprises pressurizing the metallic bladder such that the metallic bladder expands and imparts a compressive force, pressing the preform structure against the number of die liners.

14. The method of claim 13 , wherein laying down the thermoplastic material to form the preform structure having the plurality of cavities further comprises laying down a braided thermoplastic material over the plurality of core parts.

15. The method of claim 12 further comprising:
consolidating the preform structure to form the consolidated structure, consolidating comprising applying a magnetic field to the number of die liners to heat the preform structure to a consolidation temperature and wherein consolidating the preform structure to form the consolidated structure further comprises applying the magnetic field to the plurality of mandrels, wherein the second material is Invar.

16. The method of claim 11 further comprising:
dissolving a material from within the consolidated structure.

17. The method of claim 11 , wherein the number of die liners comprises a number of smart susceptors.

18. The method of claim 11 further comprising:
consolidating the structure to form the consolidated structure, consolidating comprising applying a magnetic field to the number of die liners to heat the structure to a consolidation temperature.

19. A method of forming a consolidated structure comprising:
laying down a braided thermoplastic material onto a metallic bladder to form a

Assignees

• Boeing Co

Inventors

• Matsen Marc Rollo
• Marcoe Jeffery Lee
• Bartel Aaron William
• Moser John B
• Lyons Brett I

Classifications

• B29D24/004

  the structure having vertical or oblique ribs · CPC title

• B29C70/446

  Moulding structures having an axis of symmetry or at least one channel, e.g. tubular structures, frames · CPC title

• B29D99/0014

  provided with ridges or ribs, e.g. joined ribs · CPC title

• B29L2031/3085

  Wings · CPC title

• B29C2035/0811

  using induction · CPC title