New 6xxx aluminum alloys

Patent metadata

Field	Value
Publication number	US-2023374632-A1
Application number	US-202318224945-A
Country	US
Kind code	A1
Filing date	Jul 21, 2023
Priority date	Jan 29, 2021
Publication date	Nov 23, 2023
Grant date	—

Abstract

New 6xxx aluminum alloys are disclosed. In one embodiment, a new 6xxx aluminum alloy sheet product includes from 0.75 to 1.05 wt. % Si, from 0.65 to 0.95 wt. % Mg, wherein (wt. % Mg)/(wt. % Si) is not greater than 0.99:1, from 0.50 to 0.75 wt. % Cu, from 0.02 to 0.40 wt. % Mn, from 0.06 to 0.26 wt. % Cr, wherein (wt. % Mn)+(wt. % Cr) is at least 0.22 wt. %, from 0.01 to 0.30 wt. % Fe, up to 0.25 wt. % Zn, up to 0.20 wt. % Zr, up to 0.20 wt. % V, and up to 0.15 wt. % Ti, the balance being aluminum, optional incidental elements and impurities.

First claim

What is claimed is:

1 . A aluminum alloy sheet product comprising:
from 0.75 to 1.05 wt. % Si; from 0.65 to 0.95 wt. % Mg;
wherein (wt. % Mg)/(wt. % Si) is not greater than 0.99:1;
from 0.50 to 0.75 wt. % Cu; from 0.02 to 0.40 wt. % Mn; from 0.06 to 0.26 wt. % Cr;
wherein (wt. % Mn)+(wt. % Cr) is at least 0.22 wt. %;
from 0.01 to 0.30 wt. % Fe; up to 0.25 wt. % Zn; up to 0.20 wt. % Zr; up to 0.20 wt. % V; up to 0.15 wt. % Ti; the balance being aluminum, optional incidental elements and impurities;
wherein the aluminum alloy sheet product has a thickness of from 1.0 to 4.0 mm;
wherein the aluminum sheet product realizes a tensile yield strength (LT) of at least 315 MPa in a T6 temper, wherein the artificial aging of the T6 temper is 30 minutes at 225° C. (437° F.).

2 . The aluminum alloy sheet product of claim 1 , wherein the aluminum alloy includes at least 0.80 wt. % Si.

3 . The aluminum alloy sheet product of claim 2 , wherein the aluminum alloy includes not greater than 1.0 wt. % Si.

4 . The aluminum alloy sheet product of claim 1 , wherein the aluminum alloy includes at least 0.70 wt. % Mg.

5 . The aluminum alloy sheet product of claim 4 , wherein the aluminum alloy includes not greater than 0.90 wt. % Mg.

6 . The aluminum alloy sheet product of claim 1 , wherein (wt. % Mg)/(wt. % Si) is not greater than 0.95:1.

7 . The aluminum alloy sheet product of claim 6 , wherein (wt. % Mg)/(wt. % Si) is at least 0.7:1.

8 . The aluminum alloy sheet product of claim 1 , wherein the aluminum alloy includes at least 0.55 wt. % Cu.

9 . The aluminum alloy sheet product of claim 8 , wherein the aluminum alloy includes not greater than 0.73 wt. % Cu.

10 . The aluminum alloy sheet product of claim 1 , wherein the aluminum alloy includes at least 0.04 wt. % Mn.

11 . The aluminum alloy sheet product of claim 10 , wherein the aluminum alloy includes not greater than 0.35 wt. % Mn.

12 . The aluminum alloy sheet product of claim 1 , wherein the aluminum alloy includes at least 0.08 wt. % Cr.

13 . The aluminum alloy sheet product of claim 12 , wherein the aluminum alloy includes not greater than 0.24 wt. % Cr.

14 . The aluminum alloy sheet product of claim 1 , wherein (wt. % Mn)+(wt. % Cr) is at least 0.24 wt. %.

15 . The aluminum alloy sheet product of claim 1 , wherein the aluminum alloy sheet product realizes at least one of:
a three-point bend extension of at least 10.0 mm in the T6 temper; a three-point bend extension of at least 16.0 mm in the T4 temper; a maximum depth of attack of not greater than 200 micrometers when tested in accordance with ASTM G110-92(2015) for 6 hours; and an f/r of at least 0.05.

16 . The aluminum alloy sheet product of claim 1 , wherein the aluminum alloy sheet product is fully recrystallized.

17 . The aluminum alloy sheet product of claim 1 , wherein the aluminum alloy sheet product realizes at least one of:
an area weighted average grain size of not greater than 50 micrometers; at least 10 vol. % cube texture; and a dispersoid area fraction of at least 0.5%.

18 . The aluminum alloy sheet product of claim 1 , wherein, in the T4 or T43 temper, the aluminum alloy sheet product realizes an increase of not greater than 15 MPa in tensile yield strength (LT) over the period of 2 weeks of natural aging to 6 months of natural aging.

19 . The aluminum alloy sheet product of claim 1 , wherein the aluminum alloy sheet product realizes not greater than 21 MPa strength loss in tensile yield strength (LT) over the period of 2 weeks of natural aging to 6 months of natural aging relative to the T6 temper.

20 . An automotive sheet product made from the aluminum alloy sheet product of claim 1 .

Assignees

• Arconic Tech Llc

Inventors

• Karabin Lynette M
• Hosch Timothy A
• Mooy Dirk C
• Long Russell S

Classifications

• C22C21/02 Primary

  with silicon as the next major constituent · CPC title

• C22F1/002

  by rapid cooling or quenching; cooling agents used therefor · CPC title

• C22F1/05

  of alloys of the Al-Si-Mg type, i.e. containing silicon and magnesium in approximately equal proportions · CPC title