Aluminum alloy with additions of scandium, zirconium and erbium

Patent metadata

Field	Value
Publication number	US-9797030-B2
Application number	US-201615277052-A
Country	US
Kind code	B2
Filing date	Sep 27, 2016
Priority date	Feb 29, 2012
Publication date	Oct 24, 2017
Grant date	Oct 24, 2017

Abstract

An aluminum alloy including additions of scandium, zirconium, erbium and, optionally, silicon.

First claim

What is claimed is:

1. A method for forming an aluminum alloy comprising the steps of:
forming a molten mass of aluminum comprising additions of scandium, zirconium, erbium and, optionally, silicon;
cooling said molten mass to form a solid mass;
during a first heat treating step, maintaining said solid mass at a temperature ranging from about 275 to about 325° C. for a first predetermined amount of time; and
after said first heat treating step, maintaining said solid mass at a temperature ranging from about 375 to about 425° C. for a second predetermined amount of time.

2. The method of claim 1 wherein said first predetermined amount of time is about 2 to about 8 hours.

3. The method of claim 1 wherein said second predetermined amount of time is about 4 to about 12 hours.

4. The method of claim 1 wherein said first predetermined amount of time is about 2 to about 8 hours and said second predetermined amount of time is about 4 to about 12 hours.

5. The method of claim 1 wherein said molten mass consists essentially of said aluminum, said scandium, said zirconium, said erbium and, optionally, said silicon.

6. The method of claim 5 wherein iron is present in said molten mass as an impurity.

7. The method of claim 6 wherein said iron is present at a concentration of at most about 0.0025 at. %.

8. The method of claim 1 wherein:
said scandium comprises at most about 0.1 at. % of said molten mass;
said zirconium comprises at most about 0.1 at. % of said molten mass;
said erbium comprises at most about 0.05 at. % of said molten mass; and
said silicon comprises from 0 to about 0.1 at. % of said molten mass.

9. The method of claim 1 wherein:
said scandium comprises at most about 0.08 at. % of said molten mass;
said zirconium comprises at most about 0.08 at. % of said molten mass; and
said erbium comprises at most about 0.04 at. % of said molten mass.

10. The method of claim 9 wherein said molten mass is substantially free of said silicon.

11. The method of claim 1 wherein:
said scandium comprises at most about 0.06 at. % of said molten mass;
said zirconium comprises at most about 0.06 at. % of said molten mass; and
said erbium comprises at most about 0.02 at. % of said molten mass.

12. The method of claim 11 wherein said molten mass is substantially free of said silicon.

13. The method of claim 1 wherein:
said scandium comprises at most about 0.08 at. % of said molten mass;
said zirconium comprises at most about 0.08 at. % of said molten mass;
said erbium comprises at most about 0.04 at. % of said molten mass; and
said silicon comprises at most about 0.08 at. % of said molten mass.

14. The method of claim 1 wherein:
said scandium comprises at most about 0.06 at. % of said molten mass;
said zirconium comprises at most about 0.06 at. % of said molten mass;
said erbium comprises at most about 0.02 at. % of said molten mass; and
said silicon comprises at most about 0.04 at. % of said molten mass.

15. The method of claim 1 wherein said molten mass consists essentially of said aluminum, said scandium, said zirconium, said erbium, and said silicon.

16. The method of claim 1 further comprising the step of, prior to said first heat treating step, homogenizing said solid mass at a temperature of about 600 to about 660° C. for about 1 to about 20 hours.

17. A method for forming an aluminum alloy comprising the steps of:
forming a molten mass consisting of:
a non-zero quantity of scandium, present at a concentration of at most about 0.1 at. %;
a non-zero quantity of zirconium, present at a concentration of at most about 0.1 at. %;
a non-zero quantity of erbium, present at a concentration of at most about 0.05 at. %;
from 0 to about 0.1 at. % silicon; and
aluminum, forming substantially the balance of said molten mass;

cooling said molten mass to form a solid mass;
during a first heat treating step, maintaining said solid mass at a temperature ranging from about 275 to about 325° C. for about 2 to about 8 hours; and
after said first heat treating step, maintaining said solid mass at a temperature ranging from about 375 to about 425° C. for about 4 to about 12 hours.

18. The method of claim 17 wherein iron is present in said molten mass as an impurity.

19. The method of claim 17 wherein the content of silicon in said molten mass is at least about 0.02 at. %.

20. The method of claim 17 wherein:
the content of scandium in said molten mass is at most about 0.08 at. %;
the content of zirconium in said molten mass is at most about 0.08 at. %;
the content of erbium in said molten mass is at most about 0.04 at. %; and
the content of silicon in said molten mass is about 0 at. %.

Assignees

• Boeing Co
• Ford Global Tech Llc
• Univ Northwestern

Inventors

• Huskamp Christopher S
• Booth-Morrison Christopher
• Dunand David C
• Seidman David N
• Boileau James M
• Ghaffari Bita

Classifications

• C22F1/04

  of aluminium or alloys based thereon · CPC title

• B22D21/007

  with low melting point, e.g. Al 659 degrees C, Mg 650 degrees C · CPC title

• C22C21/02

  with silicon as the next major constituent · CPC title

• C22F1/043

  of alloys with silicon as the next major constituent · CPC title

• C22C21/00 Primary

  Alloys based on aluminium · CPC title