CORROSION RESISTANT ALUMINUM ALLOY SUBSTRATES AND METHODS OF PRODUCING THE SAME

• US 20090061218A1
• Filed: 08/22/2008
• Published: 03/05/2009
• Est. Priority Date: 08/28/2007
• Status: Active Grant

• Current Assignee: Arconic Inc. (Howmet Aerospace, Inc.)
• Original Assignee: Alcoa Incorporated (Howmet Aerospace, Inc.)
• Inventors: Lee, Wilson C., Sohi, Jaskirat, Askin, Albert L., Vega, Luis Fanor, Zediak, Clinton, Levendusky, Thomas L., Robare, Kevin M., Guthrie, Joseph D.
• Granted Patent: US 8,309,237 B2
• Time in Patent Office: Days
• US Class Current: 428/336
• CPC Class Codes: C23C 18/00 Chemical coating by decomposition of either liquid compounds or solutions of the coating forming compounds, without leaving reaction products of surface material in the coating; Contact plating
• CPC Class Codes: C23C 18/122 Inorganic polymers, e.g. silanes, polysilazanes, polysiloxanes
• CPC Class Codes: C23C 18/1254 Sol or sol-gel processing
• CPC Class Codes: C25D 11/08 containing inorganic acids
• CPC Class Codes: C25D 11/16 Pretreatment , e.g. desmutting
• CPC Class Codes: C25D 11/24 Chemical after-treatment
• CPC Class Codes: Y10T 428/249953 Composite having voids in a component [e.g., porous, cellular, etc.]
• CPC Class Codes: Y10T 428/264 Up to 3 mils
• CPC Class Codes: Y10T 428/265 1 mil or less

Abstract

Aluminum alloy products comprising an aluminum alloy base and a sulfate-phosphate oxide zone integral therewith are disclosed. Methods of making the same are also disclosed.

Claims

1. A wrought aluminum alloy product comprising:

an aluminum alloy base;

a sulfate-phosphate oxide zone integral with the base, wherein the sulfate-phosphate oxide zone has an average thickness of at least about 8 microns; and

a silicon-containing polymer zone at least partially overlapping the sulfate-phosphate oxide zone, wherein the silicon-containing polymer zone comprises a coating portion on a surface of the aluminum alloy base;

wherein the wrought aluminum alloy product has a fatigue life that is better than the fatigue life of a Type-II anodized aluminum alloy product of similar composition, shape, and temper and having a similar oxide thickness.

2. The product of claim 1, wherein the wrought aluminum alloy product is a forged aluminum alloy product.

3. The product of claim 2, wherein the forged aluminum alloy product is an aluminum alloy wheel product.

4. The product of claim 3, wherein the aluminum alloy wheel product comprises at least one of a 2XXX and 6XXX series aluminum alloy.

5. The product of claim 4, wherein the aluminum alloy wheel product has a cornering fatigue life that is better than the cornering fatigue life of a Type-II anodized aluminum alloy wheel product of similar composition, shape and temper and having a similar oxide thickness.

6. The product of claim 4, wherein the aluminum alloy wheel product has a radial fatigue life that is better than the radial fatigue life of a Type-II anodized aluminum alloy wheel product of similar composition, shape and temper and having a similar oxide thickness.

7. The product of claim 1, wherein the wrought aluminum alloy product is a sheet or plate product.

8. The product of claim 1, wherein the wrought aluminum alloy product is an extrusion product.

9. The product of claim 1, wherein the wrought aluminum alloy product is a casting product.

10. The product of claim 1, wherein the sulfate-phosphate oxide zone has an average thickness of at least about 12 microns.

11. The product of claim 1, wherein the silicon-containing polymer is polysilazane.

12. The product of claim 1, wherein the wrought aluminum alloy product has a fatigue life that is better than the fatigue life of a Type-II anodized and sodium dichromate sealed aluminum alloy product of similar composition, shape and temper and having a similar oxide thickness.