Heat treatable aluminum alloys having magnesium and zinc and methods for producing the same

Patent metadata

Field	Value
Publication number	US-9850556-B2
Application number	US-201715424652-A
Country	US
Kind code	B2
Filing date	Feb 3, 2017
Priority date	Mar 9, 2013
Publication date	Dec 26, 2017
Grant date	Dec 26, 2017

Abstract

New heat treatable aluminum alloys having magnesium and zinc are disclosed. The new aluminum alloys generally contain 3.0-6.0 wt. % Mg, 2.5-5.0 wt. % Zn, where (wt. % Mg)/(wt. % Zn) is from 0.60 to 2.40.

First claim

What is claimed is:

1. An aluminum alloy sheet product consisting of:
3.75-6.0 wt. % Mg;
2.5-5.0 wt. % Zn;
wherein (wt. % Mg)/(wt. % Zn) is from 0.75 to 2.40

up to 1.0 wt. % Cu;
up to 0.5 wt. % Si;
optionally at least one secondary element selected from the group consisting of Zr, Sc, Cr, Mn, Hf, V, Ti, and rare earth elements, and in the following amounts:
up to 0.20 wt. % Zr;
up to 0.30 wt. % Sc;
up to 0.50 wt. % Cr;
up to 1.0 wt. % Mn;
up to 0.25 wt. % each of any of Hf, V, and rare earth elements;
up to 0.15 wt. % Ti;

up to 0.35 wt. Fe; and
the balance being aluminum and other elements, wherein the aluminum alloy sheet product includes not greater than 0.15 wt. % each of these other elements, and wherein the total of these other elements does not exceed 0.35 wt. %;
wherein the aluminum alloy sheet product is in the form of an automotive product or an aerospace product.

2. The aluminum alloy sheet product of claim 1 , wherein the aluminum alloy sheet product includes at least 3.75 wt. % Mg.

3. The aluminum alloy sheet product of claim 1 , wherein the aluminum alloy sheet product includes not greater than 5.5 wt. % Mg.

4. The aluminum alloy sheet product of claim 1 , wherein the aluminum alloy sheet product includes not greater than 5.0 wt. % Mg.

5. The aluminum alloy sheet product of claim 1 , wherein the aluminum alloy sheet product includes not greater than 4.5 wt. % Mg.

6. The aluminum alloy sheet product of claim 1 , wherein the aluminum alloy sheet product includes at least 2.75 wt. % Zn.

7. The aluminum alloy sheet product of claim 1 , wherein the aluminum alloy sheet product includes at least 3.0 wt. % Zn.

8. The aluminum alloy sheet product of claim 1 , wherein the aluminum alloy sheet product includes at least 3.25 wt. % Zn.

9. The aluminum alloy sheet product of claim 1 , wherein the aluminum alloy sheet product includes not greater than 4.5 wt. % Zn.

10. The aluminum alloy sheet product of claim 1 , wherein the aluminum alloy sheet product includes not greater than 4.0 wt. % Zn.

11. The aluminum alloy sheet product of claim 1 , wherein (wt. % Mg)/(wt. % Zn) is at least 0.75.

12. The aluminum alloy sheet product of claim 1 , wherein (wt. % Mg)/(wt. % Zn) is at least 0.90.

13. The aluminum alloy sheet product of claim 1 , wherein (wt. % Mg)/(wt. % Zn) is at least 1.00.

14. The aluminum alloy sheet product of claim 1 , wherein (wt. % Mg)/(wt. % Zn) is at least 1.02.

15. The aluminum alloy sheet product of claim 1 , wherein (wt. % Mg)/(wt. % Zn) is not greater than 2.00.

16. The aluminum alloy sheet product of claim 1 , wherein (wt. % Mg)/(wt. % Zn) is not greater than 1.75.

17. The aluminum alloy sheet product of claim 1 , wherein (wt. % Mg)/(wt. % Zn) is not greater than 1.50.

18. The aluminum alloy sheet product of claim 1 , wherein the aluminum alloy sheet product is one of a hood, a fender, a door, a roof, a trunk lid, or a body-in-white product of an automobile.

19. A method comprising:
(a) casting an aluminum alloy into an aluminum alloy body, wherein the aluminum alloy body consists of:
3.75-6.0 wt. % Mg;
2.5-5.0 wt. % Zn;
wherein (wt. % Mg)/(wt. % Zn) is from 0.75 to 2.40

up to 1.0 wt. % Cu;
up to 0.5 wt. % Si;
optionally at least one secondary element selected from the group consisting of Zr, Sc, Cr, Mn, Hf, V, Ti, and rare earth elements, and in the following amounts:
up to 0.20 wt. % Zr;
up to 0.30 wt. % Sc;
up to 0.50 wt. % Cr;
up to 1.0 wt. % Mn;
up to 0.25 wt. % each of any of Hf, V, and rare earth elements;
up to 0.15 wt. % Ti;

up to 0.35 wt. Fe; and
the balance being aluminum and other elements, wherein the aluminum alloy sheet product includes not greater than 0.15 wt. % each of these other elements, and wherein the total of these other elements does not exceed 0.35 wt. %;

(b) processing the aluminum alloy body into one of a W temper and a T temper, wherein the processing step (b) comprises solution heat treating and then quenching the aluminum alloy body.

20. The method of claim 19 , wherein the processing step (b) comprises artificial aging the aluminum alloy body to one of a T6, T7 or a T8 temper, wherein the aluminum alloy body in the T6 or T7 temper realizes a higher strength than the aluminum alloy body in a T4 temper, or wherein the aluminum alloy body in the T8 temper realizes a higher strength than the aluminum alloy body in a T3 temper.

Assignees

• Arconic Inc

Inventors

• Lin Jen

Classifications

• B22D21/007

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

• C22C21/06 Primary

  with magnesium as the next major constituent · CPC title

• C22C21/08

  with silicon · CPC title

• C22F1/047 Primary

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