Thermoplastic composite parts having integrated metal fittings and method of making the same

• US 20070175573A1
• Filed: 01/29/2007
• Published: 08/02/2007
• Est. Priority Date: 02/02/2006
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Wilkerson, Randall D., Rubin, Alexander M., Fox, James R.
• Granted Patent: US 9,102,103 B2
• Time in Patent Office: Days
• US Class Current: 156/196
• CPC Class Codes: B29C 70/34 and shaping or impregnating by compression , i.e. combined with compressing after the lay-up operation
• CPC Class Codes: B29C 70/50 for producing articles of indefinite length, e.g. prepregs, sheet moulding compounds [SMC] or cross moulding compounds [XMC]
• CPC Class Codes: B29C 70/525 Component parts, details or accessories; Auxiliary operations
• CPC Class Codes: B29C 70/545 Perforating, cutting or machining during or after moulding
• CPC Class Codes: B29C 70/86 Incorporated in coherent impregnated reinforcing layers, e.g. by winding
• CPC Class Codes: B29C 70/885 with incorporated metallic wires, nets, films or plates as lost heating elements B29C35/0272, B29C61/0625
• CPC Class Codes: B29D 99/0007 having a variable cross-section
• CPC Class Codes: B29K 2101/12 Thermoplastic materials
• CPC Class Codes: B32B 15/08 of synthetic resin
• CPC Class Codes: B32B 2262/101 Glass fibres
• CPC Class Codes: B32B 2262/106 Carbon fibres, e.g. graphite fibres
• CPC Class Codes: B32B 2605/003 Interior finishings
• CPC Class Codes: B32B 2605/18 Aircraft
• CPC Class Codes: B32B 27/08 of synthetic resin
• CPC Class Codes: B32B 27/285 comprising polyethers
• CPC Class Codes: B32B 27/286 comprising polysulphones; polysulfides
• CPC Class Codes: B32B 27/288 comprising polyketones
• CPC Class Codes: B32B 3/085 spaced apart pieces on the surface of a layer
• CPC Class Codes: Y10T 156/1002 with permanent bending or reshaping or surface deformation of self sustaining lamina

Abstract

Thermoplastic composite parts having integrated metal fittings are manufactured using a continuous compression molding process. Automated equipment or hand lay-up are used to collate composite material plies and metal fittings into a multi-layer stack. Each stack contains all plies, including ply build-up areas, tacked in the proper location to maintain orientation and location. Multiple lay-ups may be cut from each stack. The lay-ups are placed in tooling containing part features and are continuously fed through a performing station where the lay-ups are preformed into the approximate shape of the finished part. Following pre-forming, the tooling is moved incrementally through a consolidation station where a compression press presses successive sections of the tooling to form a single integrated thermoplastic composite laminate part having integrated metal fittings, which may include areas of differing thickness.

Claims

1. A method of manufacturing a thermoplastic composite laminate having at least one integrated metal fitting, comprising the steps of:

(A) forming a lay-up including a multiple ply stack of thermoplastic composite material and at least one metal fitting;

(B) feeding the lay-up through a press; and

(C) consolidating the plies and the metal fitting using the press.

2. The method of claim 1, wherein step (A) includes introducing a thermoplastic film between the metal fitting and one of the plies.

3. The method of claim 1, wherein step (A) includes forming a joint between the metal fitting and plies in the stack.

4. The method of claim 1, wherein step (A) includes tacking the plies together.

5. The method of claim 1, further comprising the step of:

(D) preforming the lay-up into the approximate shape of the laminate.

6. The method of claim 1, further comprising the step of:

(D) placing the lay-up between at least two tools, and

wherein step (B) is performed by feeding the tools and the lay-up into the press.

7. The method of claim 1, wherein the thermoplastic composite material includes a matrix resin component having a free flowing temperature, and the method further comprises the steps of:

(D) preforming the lay-up into the approximate shape of the laminate; and

(E) heating the preformed lay-up to at least the free flowing temperature of the matrix resin component of the thermoplastic composite material before step (C) is performed.

8. The method of claim 1, wherein the method further comprises the step of:

(D) preforming the lay-up into the approximate shape of the laminate, and

wherein step (C) includes pressing a tool against the preformed lay-up to impart features of the tool on the preformed lay-up.

9. The method of claim 1, wherein step (B) is performed by incrementally moving the lay-up through the press.

10. The method of claim 1, wherein:

step (B) includes preforming the lay-up into the approximate shape of the laminate, and moving the preformed lay-up through the press in incremental steps, and

step (C) includes applying pressure to the preformed lay-up each time the lay-up is incrementally moved.

11. A thermoplastic composite laminate structure manufactured by the method of claim 1.

12. A method of manufacturing composite laminates having metal fittings in a continuous process, comprising the steps of:

(A) collating multiple plies of a thermoplastic composite material;

(B) providing metal fittings for the laminates;

(C) forming a plurality of lay-ups, each including the collated plies and at least one of the metal fittings;

(D) preforming each of the lay-ups formed in step (C) into the approximate shape of the laminate; and

(E) consolidating the plies and the metal fitting in the lay-ups by incrementally moving the lay-ups through a continuous compression molding press.

13. The method of claim 12, wherein step (A) includes introducing a film of thermoplastic film between each of the metal fittings and the plies.

14. The method of claim 12, wherein the method further comprises:

(F) includes tacking the plies together to form a plurality of tacked stacks, wherein the plies and the metal fittings in each stack are held in fixed relationship to each other.

15. The method of claim 12, wherein step (C) includes forming a joint between the metal fitting and the plies in each of the stacks.

16. The method of claim 12, further comprising the step of:

(E) placing each of the lay-ups between at least two tools.

17. The method of claim 12, wherein the thermoplastic composite material includes a matrix resin component having a free flowing temperature, and the method further comprises the step of:

(E) heating each of the preformed lay-ups to at least the free flowing temperature of the matrix resin component of the thermoplastic composite material before step (E) is performed.

18. The method of claim 12, wherein step (E) includes pressing a tool against each of the preformed lay-ups to impart features of the tool on the preformed lay-up.

19. The method of claim 12, wherein steps (C) through (E) are performed continuously.

20. The method of claim 12, further comprising the steps of:

(F) cleaning the surface of the metal fittings; and

,

(G) applying a bonding primer to the cleaned surfaces of the fittings.

21. The method of claim 20, further comprising the step of:

(G) applying a resin film to the primed surfaces of the fittings.

22. A thermoplastic laminate part having at least one integrated metal fitting, produced by a method comprising the steps of:

(A) forming a plurality of lay-ups, each of the lay-ups including a tacked stack of multiple plies of thermoplastic material and at least one metal fitting;

(B) placing a set of tooling over each of the lay-ups;

(C) continuously moving the lay-ups through a preforming station;

(D) preforming each of the lay-ups at the preforming station into the approximate shape of the part;

(E) continuously moving the tooling with the preformed lay-ups through a press; and

,

(F) consolidating the plies in the lay-ups and the fittings by compressing successive sections of the tooling as the tooling moves through the press.

23. The method of claim 22, wherein step (A) includes tacking the plies together so that the plies are held in fixed relationship to each other and to the metal fitting.

24. The method of claim 22, wherein step (B) includes feeding the tooling along with the lay-ups into the performing station.

25. The method of claim 22, further comprising the step of:

(G) heating the lay-up to the free-flowing temperature of a matrix resin component of the plies before step (F) is completed.

26. The method of claim 22, wherein step (E) includes moving the tooling with the preformed lay-ups through the press in incremental steps.