5xxx aluminum alloys and methods of making the same

Patent metadata

Field	Value
Publication number	US-2025277295-A1
Application number	US-202519209906-A
Country	US
Kind code	A1
Filing date	May 16, 2025
Priority date	Dec 12, 2022
Publication date	Sep 4, 2025
Grant date	—

Abstract

New 5xxx aluminum alloy sheet products and methods for making the same are disclosed. The new 5xxx aluminum alloy sheet products may realize a low yield point elongation (YPE) thereby facilitating reduction or elimination of Type A Lüdering (stretcher-strain lines). The new 5xxx aluminum alloy sheet products may be hot rolled into an intermediate gauge product, then cold rolled to a final gauge product, wherein no intermediate annealing occurs prior to or during the cold rolling, and then post cold roll annealing at a temperature and for a time sufficient to first realize a recovered but unrecrystallized microstructure, and then converting of at least some of the recovered but unrecrystallized microstructure to a recrystallized microstructure via a second annealing operation of the post cold roll annealing step.

First claim

What is claimed is:

1 . A method comprising:
(a) hot rolling a 5xxx aluminum alloy to an intermediate gauge product; (b) after the hot rolling step, conducting a cold rolling operation to achieve a final gauge product, wherein the cold rolling operation includes at least one cold rolling step, and wherein no intermediate annealing occurs prior to or during the cold rolling operation; (c) after the cold rolling operation, post cold roll annealing the final gauge product, wherein the post cold roll annealing step (c) comprises:
(i) first annealing at a first temperature for a first duration, wherein, due to the first annealing step, the final gauge product contains a recovered but unrecrystallized microstructure; and
(ii) after the first annealing step, applying a second annealing step to the final gauge product, thereby converting at least some of the recovered but unrecrystallized microstructure to a recrystallized microstructure.

2 . The method of claim 1 , wherein the post cold roll annealing step comprises annealing the final gauge product at a temperature and for a time sufficient for the final gauge product to realize a YPE of not greater than 0.60%.

3 . The method of claim 2 , wherein the final gauge product realizes at least one of:
(A) an area weighted average grain size of not greater than 40 micrometers; (B) a Brass texture amount of not greater than 14%; and (C) an S texture amount of not greater than 19%.

4 . The method of claim 3 , wherein, due to the second annealing step, the final gauge product realizes at least two of (A), (B) and (C).

5 . The method of claim 1 , wherein the final gauge product realizes an area weighted average grain size of from 15 to 39 micrometers.

6 . The method of claim 5 , wherein the final gauge product realizes a Brass texture amount of from 1% to 13%.

7 . The method of claim 6 , wherein the final gauge product realizes an S texture amount of from 5% to 18%, or an S texture amount of not greater than 17%, or an S texture amount of not greater than 16%, or an S texture amount of not greater than 15%, or an S texture amount of not greater than 14%.

8 . The method of claim 1 , wherein the second temperature is at least 25° F. higher than the first temperature;
wherein the first duration is at least 30 minutes;
wherein the second duration is at least 1 second.

9 . The method of claim 8 , wherein the first temperature is below a recrystallization temperature of the final gauge product, and wherein the second temperature is above the recrystallization temperature of the final gauge product.

10 . The method of claim 9 , wherein the first temperature is from 350° F. to 500° F.

11 . The method of claim 10 , wherein the first duration is from at least 1 hour to not greater than 10 days.

12 . The method of claim 11 , wherein the second temperature is from greater than 500° F. to 900° F.

13 . The method of claim 12 , wherein the second duration is from 5 seconds to 48 hours.

14 . The method of claim 1 , wherein the cold rolling operation is accomplished with a single cold rolling pass.

15 . The method of claim 1 , wherein the cold rolling operation is accomplished with multiple cold rolling passes.

16 . The method of claim 1 , wherein the cold rolling operation comprises reducing a thickness of the intermediate gauge product by from 25% to 80%.

17 . The method of claim 1 , wherein the hot rolling comprises hot rolling an ingot or a continuously cast strip of the 5xxx aluminum alloy.

18 . A 5xxx aluminum alloy sheet product comprising from 4.0 to 6.0 wt. % Mg and having a thickness of from 0.5 to 5.0 mm, wherein the 5xxx aluminum alloy sheet product is at least 60% recrystallized and realizes an YPE of not greater than 0.60%; wherein the 5xxx aluminum alloy sheet product realizes at least one of:
(A) an area weighted average grain size of not greater than 40 micrometers; (B) a Brass texture amount of not greater than 14%; and (C) an S texture amount of not greater than 19%.

19 . The 5xxx aluminum alloy sheet product of claim 18 , comprising:
from 4.0 to 5.0 wt. % Mg up to 0.50 wt. % Mn; up to 0.75 wt. % Zn; up to 0.35 wt. % Fe; up to 0.20 wt. % Si; up to 0.15 wt. % Cu; up to 0.10 wt. % Cr; up to 0.10 wt. % Ti; the balance being aluminum, optional incidental elements and impurities.

20 . The 5xxx aluminum alloy sheet product of claim 19 , wherein the 5xxx aluminum alloy includes at least 0.25 wt. % Zn, or at least 0.30 wt. % Zn, or at least 0.35 wt. % Zn, or at least 0.40 wt. % Zn, or at least 0.45 wt. % Zn, or at least 0.50 wt. % Zn.

Assignees

• Arconic Tech Llc

Inventors

• Jiang Xu
• Karabin Lynette M
• Sauza Daniel J
• Hosch Timothy A
• Mooy Dirk C
• Butler Jr John F

Classifications

• C22C21/06 Primary

  with magnesium as the next major constituent · CPC title

• C22F1/047 Primary

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

• C22C21/08

  with silicon · CPC title