METHOD AND APPARATUS FOR BONDING DISSIMILAR MATERIALS MADE FROM METALS

• US 20080026247A1
• Filed: 07/23/2007
• Published: 01/31/2008
• Est. Priority Date: 07/25/2006
• Status: Active Grant

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan Motor Co., Ltd.
• Inventors: Fukushima, Akira, Sakurai, Hiroshi, Yamamoto, Chika, Miyamoto, Kenji, Miyamoto, Takashi, Kasukawa, Minoru, Nakagawa, Shigeyuki
• Granted Patent: US 8,476,549 B2
• Time in Patent Office: Days
• US Class Current: 428/649
• CPC Class Codes: B23K 11/115 by means of two electrodes placed opposite one another on both sides of the welded parts
• CPC Class Codes: B23K 11/20 of different metals
• CPC Class Codes: B23K 2103/20 Ferrous alloys and aluminium or alloys thereof
• CPC Class Codes: B23K 33/008 for automotive applications
• CPC Class Codes: Y10T 428/12493 Composite; i.e., plural, adjacent, spatially distinct metal components [e.g., layers, joint, etc.]
• CPC Class Codes: Y10T 428/12729 Group IIA metal-base component
• CPC Class Codes: Y10T 428/12736 Al-base component
• CPC Class Codes: Y10T 428/12778 Alternative base metals from diverse categories

Abstract

A method of bonding dissimilar metals, a bonding structure formed by such a method and a bonding apparatus for performing such a method. The resulting bond is capable of preventing corrosion (e.g., electric corrosion) resulting from contact of the dissimilar metals and obtains a dissimilar material joint exhibiting anti-corrosive property and bonding strength at low costs. The method includes overlapping two materials made from dissimilar metals having a seal material interposed therebetween and discharging the seal material from a bonding interface and bonding the two materials in direct contact with each other.

Claims

1. A method of bonding dissimilar metallic materials, comprising:

overlapping two materials, the two materials made from different metals with a seal material interposed therebetween;

discharging the interposed seal material disposed at least at a middle portion of a bonding region from a bonding interface; and

bonding the two materials by directly contacting the materials to each other.

2. The method according to claim 1, further comprising:

pressing the two overlapping materials, the pressing occurring when the seal material is discharged from the bonding interface, wherein the two materials are pressed by an indenter having a convex surface at a press bonding surface.

3. The method according to claim 1, further comprising:

pressing the two overlapping materials, the pressing occurring when the seal material is discharged from the bonding interface, wherein the two materials are pressed after a bending portion protruding from an opposite side has been formed on a bonding surface of at least one of the materials.

4. The method according to claim 1, further comprising:

reducing a deforming resistance of the seal material while the seal material is discharged from the bonding interface.

5. The method according to claim 4 wherein the deforming resistance of the seal material is reduced by heating the materials using an external heat source.

6. The method according to claim 1 wherein bonding the two materials includes a resistance welding process.

7. The method according to claim 6 wherein the resistance welding process utilizes at least one welding electrode and wherein at least one end of a welding electrode has a convex surface.

8. The method according to claim 7 wherein the two materials are bonded by a resistance spot welding process.

9. The method according to claim 7 wherein the two materials are bonded by a resistance seam welding process.

10. The method according to claim 6, further comprising:

reducing a deforming resistance of the interposed seal material when the seal material is discharged from the bonding interface, the deforming resistance reduction occurring by performing a preliminary electrical conduction using the welding electrode.

11. The method according to claim 1 wherein one of the two materials includes at least one of aluminum, aluminum alloys, magnesium, and magnesium alloys.

12. The method according to claim 11 wherein one of the two materials contains iron.

13. The method according to claim 1, further comprising:

interposing a material including a third metal differing from the two materials between at least one of the two materials and the seal material; and

discharging the seal material from the bonding interface while bonding the two overlapping materials by eutectic fusion occurring between at least one of the two materials and the third metallic material.

14. The method according to claim 12 wherein one of the two overlapping materials includes at least one of aluminum, aluminum alloys, magnesium, magnesium alloys, and wherein the other overlapping material includes iron.

15. The method according to claim 13 wherein the third metal is at least one of zinc, copper, tin, silver, and nickel.

16. The method according to claim 13 wherein the two materials are the zinc-plated steel sheet and the aluminum alloy plate, and wherein zinc plated to the zinc-plated steel sheet is used as the third metal.

17. The method according to claim 1 wherein the two materials comprises a first material and a second material having different ionization tendencies mutually.

18. A structure comprising:

at least two different metallic materials bonded to one another at a bond region, the bond region including a direct contact region between the two different metallic materials and an enclosure surrounding the bond region, the enclosure composed of at least one of a third metal different from the two metallic materials, an oxide film, and reaction products generated during the bond-forming process; and

a supplemental enclosure composed of a seal material.

19. The structure according to claim 18 wherein one of the metallic materials is aluminum, aluminum alloy, magnesium, or magnesium alloy.

20. The structure according to claim 18 wherein the third metal is one of zinc, copper, tin, silver, and nickel.

21. The structure according to claim 19 wherein the seal material is a thermoplastic material.

22. An apparatus for bonding materials made from dissimilar metals having a seal material disposed therebetween, the apparatus comprising:

means for discharging seal material from a bonding interface; and

means for directly bonding two materials upon discharge of the seal material.

23. The apparatus according to claim 22 wherein the seal material discharging means includes heating means for reducing a deforming resistance of the seal material and pressing means for pressing a portion heated by the heating means.

24. The apparatus according to claim 22 wherein the welding means includes a resistance welding means.