Claims
- 1. An aluminum alloy article made of an alloy composition comprising, in weight percent:
between about 0.05 and 0.5% silicon; an amount of iron between about 0.1% and up to 1.0%; an amount of manganese up to about 2.0%; between about 0.06 and 1.0% zinc; between about 0.03 and 0.35% titanium; with the balance aluminum and inevitable impurities; wherein the manganese to iron ratio is maintained between greater than about 0.5 and less than or equal to about 6.0, and the iron and manganese amounts total greater than about 0.30% such that the article contains intermetallic compounds dispersed throughout an aluminum matrix in a volume fraction of the article of at least 0.5%, and wherein a difference in electrolytic potential between an aluminum matrix of the article and the intermetallic compounds is less than about 0.2 volts, the intermetallic compounds having an aspect ratio of less than about 5.0.
- 2. The article of claim 1, wherein the ratio of manganese to iron is further limited to a lower limit of 0.75 and an upper limit of about 5.0, and the manganese and iron total amount is at least about 0.6%.
- 3. The article of claim 2, wherein the manganese to iron ratio is between about 1.0 and 4.0, and the total amount of manganese and iron is between about 0.70 and 1.2%.
- 4. The article of claim 1, wherein the intermetallic compounds are primarily at least one of iron-aluminum-manganese compounds or manganese-aluminum compounds.
- 5. The article of claim 1, wherein iron is between about 0.15 and 0.35% Fe, and manganese is between about 0.4 and 0.9% for the ratio and the total amounts of manganese and iron ranges between about 0.6 and 3.0%.
- 6. The article of claim 1, wherein the volume fraction is greater than about 2.0%.
- 7. The article of claim 1, further comprising up to about 0.7% copper, less than about 1.0% magnesium; less than about 0.01% nickel, and up to about 0.5% chromium.
- 8. The article of claim 1, wherein the intermetallic compounds have a size range of between about 0.5 and 5 microns.
- 9. In a method of making a heat exchanger including the step of diametrically expanding heat exchanger tubing, the improvement comprising making the tubing to be diametrically expanded from the alloy composition of claim 1.
- 10. The method of claim 9, wherein the tubing is an extruded tubing.
- 11. The method of claim 9, wherein ends of the tubing are inserted in an end sheet of the heat exchanger prior to the diametrical expansion, and a length for each tubing extends beyond the end sheet after the diametrical expansion step for attachment to a heat exchanger header, improved formability of the alloy composition enhancing consistent generation of a sufficient length for header attachment.
- 12. In a method of extruding tubing from an aluminum alloy starting material, the improvement comprising making the aluminum alloy starting material from the alloy composition of claim 1.
- 13. The method of claim 12, further comprising using the extruded tubing to make heat exchangers.
- 14. A heat exchanger having a component made from the alloy of claim 1.
- 15. The heat exchanger of claim 14, wherein the component is tubing or sheet product.
- 16. A method of improving the formability and corrosion resistance of an aluminum alloy article without a loss of hot workability, comprising:
providing an alloy composition comprising alloying amounts, in weight percent, of between about 0.05 and 0.5% silicon, an amount of manganese up to about 2.0%, an amount of iron between about 0.1% and up to about 1.0%, between about 0.03 and 0.35% titanium, and between about 0.06 and 1.0% zinc, with the balance aluminum and inevitable impurities, and forming the article from the alloy composition; wherein the ratio of manganese to iron in the alloy composition is controlled between about 0.5 and 6.0, and the total amount of iron and manganese in the composition is controlled to be greater than about 0.3% so as to form a finished microstructure in the article with greater than about 0.5 volume fraction of intermetallic compounds, the intermetallic compounds having an aspect ratio less than 5.0, and wherein an electrolytic potential difference between an aluminum matrix of the article and the intermetallic compounds is less than about 0.2 volts.
- 17. The method of claim 16, wherein the ratio of manganese to iron is further limited to a lower limit of 0.75 and an upper limit of about 5.0, and the manganese and iron total amount is at least about 0.6%.
- 18. The method of claim 16, wherein the intermetallic compounds are primarily at least one of iron-aluminum-manganese compounds or manganese-aluminum compounds.
- 19. The method of claim 16, wherein iron is between about 0.15 and 0.35% Fe, and manganese is between about 0.4 and 0.9% for the ratio and the total amounts of manganese and iron ranges between about 0.6 and 3.0%.
- 20. The method of claim 16, wherein the volume fraction is greater than about 2.0%.
Parent Case Info
[0001] This application claims priority under 35 U.S.C. §119(e) from provisional patent application serial No. 60/171,598, filed on Dec. 23, 1999.
Provisional Applications (1)
|
Number |
Date |
Country |
|
60171598 |
Dec 1999 |
US |
Divisions (1)
|
Number |
Date |
Country |
Parent |
09564053 |
May 2000 |
US |
Child |
10225378 |
Aug 2002 |
US |