System and method for manufacturing magnesium body panels with improved corrosion resistance

• US 8,866,044 B2
• Filed: 05/04/2011
• Issued: 10/21/2014
• Est. Priority Date: 05/04/2011
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Sachdev, Anil K., Carter, Jon T.
• Primary Examiner(s): Evans, Geoffrey S
• Application Number:
  US13/100,497
• Publication Number:
  US 20120280535A1
• Time in Patent Office: 1,266 Days
• Field of Search: 148/525, 148/565, 148/666, 148/667, 219/121.72, 219/121.67, 219/121.65, 219/121.66, 219/121.8, 72/47
• US Class Current: 219/121.72
• CPC Class Codes: B23K 2101/006 Vehicles
• CPC Class Codes: B23K 2103/15 Magnesium or alloys thereof
• CPC Class Codes: B23K 26/38 by boring or cutting

Abstract

A magnesium alloy panel for a vehicle includes a first region and a second region extending from the first region to an edge. The first region has a first microstructure having a first corrosion resistance. The second region has a second microstructure different than the first microstructure and has a second corrosion resistance greater than the first corrosion resistance. A system for mass producing magnesium alloy panels includes a forming apparatus and a laser cutting apparatus. The forming apparatus forms a panel having a first microstructure having a first corrosion resistance. The laser cutting apparatus cuts the panel to form the edge using a laser, and forms the second microstructure while forming the edge. The second microstructure is different than the first microstructure and has a second corrosion resistance greater than the first corrosion resistance. A method for mass producing magnesium alloy panels is also provided.

Claims

1. A manufacturing system for mass producing magnesium alloy panels, comprising:

a forming apparatus configured to form a panel comprising magnesium having a three dimensional shape and a first corrosion resistance; and

a laser cutting apparatus comprising a laser and a feeding apparatus, wherein the laser is configured to cut the panel to form an edge comprising a molten material, and the feeding apparatus is configured to introduce an alloying element as a solid wire to the molten material adjacent to a region of the panel where the laser cuts so as to create an intermetallic phase in the region to provide a second corrosion resistance greater than the first corrosion resistance.

2. The manufacturing system of claim 1, wherein the panel comprising magnesium has N phases and the region of the panel having the second corrosion resistance has N+M phases, N and M being integers greater than zero.

3. The manufacturing system of claim 1, wherein the panel comprising magnesium further comprises aluminum, zinc, tin, manganese, or combinations thereof.

4. The manufacturing system of claim 1, wherein the alloying element is an alloying element present in the panel as received by the laser cutting apparatus.

5. The manufacturing system of claim 1, wherein the alloying element is not present in the panel as received by the laser cutting apparatus.

6. The manufacturing system of claim 1, wherein the forming apparatus forms the panel using one of a stamping process and a hot metal gas forming process.

7. The manufacturing system of claim 1, wherein the forming apparatus forms the panel by casting the panel.

8. The manufacturing system of claim 1, wherein the alloying element is selected from a group consisting of:

aluminum, zinc, tin, manganese, rare earth metals, magnesium, and combinations thereof.

9. The manufacturing system of claim 1, wherein the panel comprises an alloy of magnesium, aluminum, and zinc.

10. The manufacturing system of claim 9, wherein the intermetallic phase comprises Mg₁₇Al₁₂.

11. A method for mass producing magnesium alloy panels, comprising:

forming a panel comprising magnesium having a first corrosion resistance;

cutting the panel to form an edge comprising a molten material using a laser; and

introducing an alloying element as a solid wire to the molten material adjacent to a region of the panel where the laser cuts so as to create an intermetallic phase in the region to provide a second corrosion resistance greater than the first corrosion resistance.

12. The method of claim 11, further comprising forming the panel using one of a hot metal gas forming process, a stamping process, and a casting process.

13. The method of claim 11, wherein the panel comprising magnesium further comprises aluminum, zinc, tin, manganese, or combinations thereof.

14. The method of claim 11, wherein

the introducing of the alloying element is to the molten material in a cutting area generated while cutting the panel to form the edge using the laser.

15. The method of claim 14, wherein the alloying element is not present in the panel when forming the panel.

16. The method of claim 14, wherein the alloying element is an alloying element present in the panel when forming the panel.

17. A manufacturing system for mass producing magnesium alloy panels, comprising:

a forming apparatus configured to form a panel comprising magnesium having a three dimensional shape and a first corrosion resistance;

a laser cutting apparatus comprising a laser and a feeding apparatus, wherein the laser is configured to cut the panel to form an edge comprising a molten material, and the feeding apparatus is configured to introduce an alloying element as a solid wire to the molten material adjacent to a region of the panel where the laser cuts so as to create an intermetallic phase in the region to provide a second corrosion resistance greater than the first corrosion resistance; and

a finishing apparatus configured to apply a surface treatment to the panel, wherein the finishing apparatus is further configured to selectively omit applying the surface treatment to the edge.

18. The manufacturing system of claim 17, wherein the panel comprising magnesium has N phases and the region of the panel having the second corrosion resistance has N+M phases, N and M being integers greater than zero.

19. The manufacturing system of claim 17, wherein the panel comprises an alloy of magnesium, aluminum, and zinc.

20. The manufacturing system of claim 19, wherein the intermetallic phase comprises Mg₁₇Al₁₂.