Radiation assisted friction welding

• US 20040050906A1
• Filed: 09/17/2002
• Published: 03/18/2004
• Est. Priority Date: 09/17/2002
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Vetrovec, Jan, Rice, Robert R.
• Granted Patent: US 6,776,328 B2
• Time in Patent Office: Days
• US Class Current: 228/112.1
• CPC Class Codes: B23K 20/1235 with temperature control during joining
• CPC Class Codes: B23K 20/1245 characterised by the apparatus

Abstract

There are provided an apparatus and method for friction welding structural members. The apparatus includes a connected shank and probe. The probe defines an absorption surface and a cavity extending thereto. The absorption surface is configured to receive electromagnetic radiation from an electromagnetic radiation source such as a light source or RF generator. The radiation heats the probe, supplementing the heat generated by friction between the probe and the structural members, and thereby increasing the speed at which the probe can be used to frictionally weld the structural materials.

Claims

1. An apparatus for friction welding at least one structural member, comprising:

a shank; and

a probe connected to said shank and configured to be actuated by said shank for friction welding the at least one structural member,

wherein at least one of said shank and said probe defines an absorption surface and a cavity extending to said absorption surface, wherein said absorption surface is configured to receive electromagnetic radiation and thereby heat said probe.

2. An apparatus for friction welding at least one structural member according to claim 1, further comprising a rotatable actuator in rotational communication with said shank such that said rotatable actuator can rotate said shank about a longitudinal axis of said probe and wherein said probe comprises a friction stir welding pin.

3. An apparatus for friction welding at least one structural member according to claim 1, further comprising a reciprocatable actuator in reciprocatable communication with said shank and wherein said probe comprises a friction stir welding blade.

4. An apparatus for friction welding at least one structural member according to claim 1, further comprising an electromagnetic radiation source configured to irradiate said absorption surface and thereby heat said probe.

5. An apparatus for friction welding at least one structural member according to claim 4, wherein said electromagnetic radiation source is a light source configured to direct light toward said absorption surface.

6. An apparatus for friction welding at least one structural member according to claim 5, further comprising a fiber optic cable configured to direct light emitted by said light source toward said absorption surface.

7. An apparatus for friction welding at least one structural member according to claim 4, wherein said electromagnetic radiation source is a radio frequency generator configured to direct radio frequency radiation toward said absorption surface.

8. An apparatus for friction welding at least one structural member according to claim 7, further comprising a waveguide configured to direct the electromagnetic radiation emitted by said radio frequency generator toward said absorption surface.

9. An apparatus for friction welding at least one structural member according to claim 4, wherein said cavity extends in a longitudinal direction through at least a portion of said probe and said electromagnetic radiation source is configured to emit electromagnetic radiation in the longitudinal direction of said probe.

10. An apparatus for friction welding at least one structural member according to claim 9, wherein said cavity extends through said shank.

11. An apparatus for friction welding at least one structural member according to claim 10, wherein said cavity defines a larger cross-sectional size in said shank than in said probe.

12. An apparatus for friction welding at least one structural member according to claim 1, wherein said absorption surface is oblique to a propagation direction of the electromagnetic radiation received from the electromagnetic radiation source.

13. An apparatus for friction welding at least one structural member according to claim 1, wherein said absorption surface is curved.

14. An apparatus for friction welding at least one structural member according to claim 1, wherein said absorption surface is conical.

15. A friction welding tool for friction welding at least one structural member, the friction welding tool comprising:

a shank;

a probe connected to said shank, wherein said probe defines an internal absorption surface, and said probe and said shank cooperate to define a cavity extending to said absorption surface;

an actuator configured to actuate said shank and said probe and thereby weld the at least one structural member; and

an electromagnetic radiation source configured to irradiate said absorption surface and thereby heat said probe, wherein said cavity extends in a longitudinal direction through a portion of said probe and said electromagnetic radiation source is configured to emit electromagnetic radiation in the longitudinal direction of said probe.

16. A friction welding tool for friction welding at least one structural member according to claim 15, wherein said probe comprises a friction stir welding pin and wherein said actuator is a rotatable actuator in rotational communication with said shank such that said rotatable actuator can rotate said pin about a longitudinal axis of said pin.

17. A friction welding tool for friction welding at least one structural member according to claim 15 wherein said probe comprises a friction stir welding blade and wherein said actuator is a reciprocatable actuator in reciprocatable communication with said shank such that said actuator can reciprocate said blade in a direction parallel to the blade.

18. A friction welding tool for friction welding at least one structural member according to claim 15, wherein said electromagnetic radiation source is a light source configured to direct light toward said absorption surface.

19. A friction welding tool for friction welding at least one structural member according to claim 15, further comprising a fiber optic cable configured to direct light emitted by said light source toward said absorption surface.

20. A friction welding tool for friction welding at least one structural member according to claim 15, wherein said electromagnetic radiation source is a radio frequency generator configured to direct radio frequency radiation toward said absorption surface.

21. A friction welding tool for friction welding at least one structural member according to claim 20, further comprising a waveguide configured to direct the electromagnetic radiation emitted by said radio frequency generator toward said absorption surface.

22. A friction welding tool for friction welding at least one structural member according to claim 15, wherein said absorption surface is oblique to a propagation direction of electromagnetic radiation emitted from said electromagnetic radiation source.

23. A friction welding tool for friction welding at least one structural member according to claim 15, wherein said absorption surface is curved.

24. A friction welding tool for friction welding at least one structural member according to claim 15, wherein said absorption surface is conical.

25. A method of friction welding at least one structural member, the method comprising:

urging a friction welding probe into the at least one structural member;

actuating the friction welding probe to frictionally weld the at least one structural member; and

irradiating an absorption surface of the probe with electromagnetic radiation, thereby heating the probe.

26. A method of friction welding at least one structural member according to claim 25, further comprising providing at least one structural member formed of a material that plasticizes at a temperature of at least 800°

C., and wherein said irradiating step comprises heating at least part of the at least one structural member to a temperature of at least 800°

C.

27. A method of friction welding at least one structural member according to claim 25, wherein the probe is a friction stir welding pin and wherein said actuating step comprises rotating the pin about a longitudinal axis and wherein said irradiating step comprises directing electromagnetic radiation in the longitudinal direction of the pin and toward the pin.

28. A method of friction welding at least one structural member according to claim 25, wherein the probe is a friction welding blade and said actuating step comprises reciprocating the blade in an interface defined by the at least one structural member.

29. A method of friction welding at least one structural member according to claim 25, wherein said irradiating step comprises irradiating the probe through a cavity defined by the probe and wherein the absorption surface is an internal surface that at least partially defines the cavity.

30. A method of friction welding at least one structural member according to claim 25, wherein said irradiating step comprises directing the electromagnetic radiation in a direction oblique relative to the absorption surface.

31. A method of friction welding at least one structural member according to claim 25, wherein said irradiating step comprises irradiating said absorption surface with light.

32. A method of friction welding at least one structural member according to claim 25, wherein said irradiating step comprises irradiating said absorption surface with radio frequency radiation.