New 6xxx aluminum alloys

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.

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 .