METHOD AND APPARATUS FOR RESIN TRANSFER MOLDING COMPOSITE PARTS

• US 20090074905A1
• Filed: 09/21/2007
• Published: 03/19/2009
• Est. Priority Date: 09/13/2007
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Matsen, Marc R., Peterson, Kim E.
• Granted Patent: US 8,372,327 B2
• Time in Patent Office: Days
• US Class Current: 425/547
• CPC Class Codes: B29C 2035/0811 using induction
• CPC Class Codes: B29C 2035/1616 using liquids
• CPC Class Codes: B29C 2035/1658 using gas
• CPC Class Codes: B29C 2035/1691 using gas-liquid mixtures
• CPC Class Codes: B29C 33/06 using radiation , e.g. electro-magnetic waves, induction heating
• CPC Class Codes: B29C 33/302 Assembling a large number of mould elements to constitute one cavity
• CPC Class Codes: B29C 35/0805 using electromagnetic radiation
• CPC Class Codes: B29C 35/16 Cooling cooling extruded material B29C48/911; cooling preforms for blow moulding B29C49/6427; cooling blown articles B29C49/66; cooling tyres during post cure inflation B29D30/0643
• CPC Class Codes: B29C 45/78 of temperature
• 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 70/54 Component parts, details or accessories; Auxiliary operations , e.g. feeding or storage of prepregs or SMC after impregnation or during ageing
• CPC Class Codes: D06N 3/00 Artificial leather, oilcloth or other material obtained by covering fibrous webs with macromolecular material, e.g. resins, rubber or derivatives thereof
• CPC Class Codes: Y10T 442/20 Coated or impregnated woven, knit, or nonwoven fabric which is not [a] associated with another preformed layer or fiber layer or, [b] with respect to woven and knit, characterized, respectively, by a particular or differential weave or knit, wherein the coating or impregnation is neither a foamed material nor a free metal or alloy layer

Abstract

A composite fabrication apparatus which may include a first tooling die and a second tooling die movable with respect to each other; a temperature control system having induction coils disposed in thermal contact with the first tooling die and the second tooling die; a first die susceptor provided on the first tooling die and a second die susceptor provided on the second tooling die and connected to the induction coils; and a cooling system disposed in thermal contact with the first tooling die and the second tooling die. A resin transfer system delivers resin from a resin source to the tooling dies to allow resin transfer molding. A composite fabrication method is also disclosed.

Claims

1. Resin transfer molding apparatus, comprising:

a pair of tooling dies each including a plurality of stacked metal sheets;

first and second susceptors respectively mounted on the first and second dies, the first and second susceptors including facing contoured surfaces defining a mold cavity for molding a part;

a temperature control system including induction coils inductively coupled with the first and second susceptors; and

,

a resin transfer system for delivering resin from a resin source to the mold cavity.

2. The apparatus of claim 1, wherein the temperature control system includes means for cooling the tooling dies.

3. The apparatus of claim 2, wherein the cooling means includes:

cooling passageways between the stacked metal plates, and

means for introducing a cooling medium into the passageways.

4. The apparatus of claim 3, wherein the means for introducing the cooling medium includes nozzles in the passageways for directing the cooling medium toward the susceptors.

5. The apparatus of claim 1, wherein the tooling dies include contoured faces respectively generally matching the contoured surfaces of the first and second susceptors.

6. The apparatus of claim 1, further comprising a dielectric shell disposed between each of the first and second susceptors and the corresponding tooling die.

7. The apparatus of claim 1 further wherein the metal sheets are spaced apart to define air gaps therebetween.

8. The apparatus of claim 7, wherein the temperature control system further includes means for introducing a cooling medium into the air gaps.

9. The apparatus of claim 1 wherein each of the stacked metal sheets includes an electrically insulating coating.

10. The apparatus of claim 1 wherein each of the first and said second susceptors comprises at least one material selected from the group consisting of a ferromagnetic material, cobalt, iron and nickel.

11. The apparatus of claim 1 wherein at least one of the susceptors includes a vent therein to allow excess resin to escape from the mold cavity.

12. The apparatus of claim 1 wherein at least one of the susceptors includes an opening coupled with the resin transfer system for allowing resin to enter the mold cavity.

13. The apparatus of claim 1, further comprising an evacuation system for evacuating the mold cavity before resin is transfer by the resin transfer system to the mold cavity.

14. The apparatus of claim 13, wherein at least one of the susceptors include a vent therein coupled with the evacuation system.

15. Resin transfer molding apparatus, comprising:

a pair of tooling dies respectively including matching contoured faces and a plurality of passageways extending generally transverse to the contoured faces;

first and second susceptors respectively mounted on the contoured faces of the tooling dies and including contoured surfaces defining a mold cavity for molding a part;

a temperature control system including—

a) induction coils inductively coupled with the first and second susceptors for heating the first and second susceptors, and

b) means for delivering coolant though the passageways to cool the first and second susceptors; and

,

a resin transfer system coupled with the tooling dies for delivering resin from a resin source to the mold cavity.

16. The apparatus of claim 15, further comprising a dielectric shell disposed between each of the first and second susceptors and a corresponding tooling die.

17. The apparatus of claim 15, wherein each of the tooling dies includes a plurality of stacked metal sheets, and the passageways are defined between the metal sheets.

18. The apparatus of claim 17, wherein each of the stacked metal sheets includes an electrically insulating coating.

19. The apparatus of claim 15, wherein each of the first and said second susceptors comprises at least one material selected from the group consisting of a ferromagnetic material, cobalt, iron and nickel.

20. The apparatus of claim 15, wherein at least one of the first and second susceptors includes a vent therein to allow excess resin to escape from the mold cavity.

21. The apparatus of claim 15, wherein at least one of the first and second susceptors includes an opening coupled with the resin transfer system for allowing resin to enter the mold cavity.

22. The apparatus of claim 15, wherein the coolant delivery means includes coolant conduits passing through the tooling dies.

23. The apparatus of claim 22, wherein the coolant delivery means includes nozzles coupled with the coolant conduits for directing the coolant through the passageways toward the susceptors.

24. The apparatus of claim 15 wherein at least one of the susceptors includes a vent therein to allow excess resin to escape from the mold cavity.

25. The apparatus of claim 15 wherein at least one of the susceptors includes an opening therein coupled with the resin transfer system for allowing resin to enter the mold cavity.

26. A method of molding a composite part, comprising the steps of:

(A) placing susceptors in a mold cavity;

(B) introducing a fiber preform into the mold cavity between the susceptors;

(C) heating the mold cavity by inductively heating the susceptors;

(D) infusing the preform with resin to form a part by transferring resin from a resin source into the mold cavity;

(E) cooling the part by cooling the susceptors; and

,

(F) removing the part after the part has been cooled.

27. The method of claim 26, further comprising the step of:

(G) evacuating the mold cavity before step (D) is completed.

28. The method of claim 26, wherein step (E) includes flowing a cooling medium over the susceptors.

29. The method of claim 28, wherein step (E) includes delivering the cooling medium to the susceptors through passageways in a die.

30. The method of claim 26, wherein step (D) includes transferring the resin from the resin source through an opening in one of the susceptors.

31. The method of claim 26, wherein step (D) includes flowing excess resin in the mold cavity through an outlet vent in one of the susceptors.

32. The method of claim 26, further comprising the step of:

(G) quickly exchanging the susceptors for different susceptors after step (F) has been completed, and

then, repeating steps (A) through (F).

33. A composite part for vehicles molded by the method of claim 26.

34. An aircraft subassembly molded by the method of claim 26.