High-strength 5xxx aluminum alloy variants and methods for preparing the same

Abstract

Described herein are novel 5xxx series aluminum alloys which exhibit high strength and formability. The aluminum alloys described herein have higher amounts of Mg content than traditional 5xxx series aluminum alloys and exhibit high strength and formability. The aluminum alloys described herein are produced according to a method including continuous casting.

1 . An aluminum alloy comprising 0-0.30 wt. % Si, 0.01-0.40 wt. % Fe, 0-1.0 wt. % Cu, 0.01-0.50 wt. % Mn, 5.0-6.0 wt. % Mg, 0-0.20 wt. % Cr, 0-0.30 wt. % Zn, 0-0.25 wt. % Ti, up to 0.15 wt. % of impurities, and Al. 
     
     
         2 . The aluminum alloy of  claim 1 , wherein the aluminum alloy comprises 0.01-0.20 wt. % Si, 0.01-0.30 wt. % Fe, 0.01-0.90 wt. % Cu, 0.01-0.40 wt. % Mn, 5.1-6.0 wt. % Mg, 0-0.10 wt. % Cr, 0-0.20 wt. % Zn, 0-0.10 wt. % Ti, up to 0.15 wt. % of impurities, and Al. 
     
     
         3 . The aluminum alloy of  claim 1 , wherein the aluminum alloy comprises 0.01-0.15 wt. % Si, 0.01-0.20 wt. % Fe, 0.05-0.80 wt. % Cu, 0.05-0.30 wt. % Mn, 5.2-6.0 wt. % Mg, 0-0.05 wt. % Cr, 0-0.10 wt. % Zn, 0-0.05 wt. % Ti, up to 0.15 wt. % of impurities, and Al. 
     
     
         4 . The aluminum alloy of  claim 1 , wherein the aluminum alloy comprises 0.01-0.06 wt. % Si, 0.02-0.15 wt. % Fe, 0.20-0.80 wt. % Cu, 0.05-0.20 wt. % Mn, 5.3-6.0 wt. % Mg, 0.001-0.02 wt. % Cr, 0-0.05 wt. % Zn, 0-0.03 wt. % Ti, up to 0.15 wt. % of impurities, and Al. 
     
     
         5 . The aluminum alloy of  claim 1 , wherein the aluminum alloy comprises 0.01-0.05 wt. % Si, 0.05-0.11 wt. % Fe, 0.30-0.80 wt. % Cu, 0.05-0.10 wt. % Mn, 5.5-5.9 wt. % Mg, 0.001-0.02 wt. % Cr, 0-0.01 wt. % Zn, 0.001-0.03 wt. % Ti, up to 0.15 wt. % of impurities, and Al. 
     
     
         6 . The aluminum alloy of  claim 1 , wherein the aluminum alloy comprises at least one of: Mg in an amount from 5.5 wt. % to 6.0 wt. %; and Cu in an amount from 0.30 wt. % to 1.0 wt. %. 
     
     
         7 . The aluminum alloy of  claim 1 , wherein a particle size of Fe-containing constituents is less than 5 microns. 
     
     
         8 . The aluminum alloy of  claim 1 , wherein a number density of Mg 2 Si particles in the aluminum alloy microstructure is at least 500/mm 2 . 
     
     
         9 . The aluminum alloy of  claim 1 , wherein the aluminum alloy has a yield strength of at least 130 MPa. 
     
     
         10 . The aluminum alloy of  claim 1 , wherein the aluminum alloy has an ultimate tensile strength of at least 300 MPa. 
     
     
         11 . The aluminum alloy of  claim 1 , wherein the aluminum alloy has a total elongation of at least 5%. 
     
     
         12 . An aluminum alloy product comprising the aluminum alloy of  claim 1 . 
     
     
         13 . The aluminum alloy product of  claim 12 , wherein the aluminum alloy product is produced by continuous casting, flash homogenization, hot rolling, and cold rolling. 
     
     
         14 . A method of producing an aluminum alloy product, comprising:
 continuously casting an aluminum alloy to form a cast product, wherein the aluminum alloy comprises 0-0.30 wt. % Si, 0.01-0.40 wt. % Fe, 0-1.0 wt. % Cu, 0.01-0.50 wt. % Mn, 5.0-6.0 wt. % Mg, 0-0.20 wt. % Cr, 0-0.30 wt. % Zn, 0-0.25 wt. % Ti, up to 0.15 wt. % of impurities, and Al;   optionally flash homogenizing the cast product;   hot rolling the cast product to produce a hot rolled product;   coiling the hot rolled product;   cold rolling the hot rolled product to produce a cold rolled product; and   annealing the cold rolled product.   
     
     
         15 . The method of  claim 14 , wherein the aluminum alloy comprises at least one of: Mg in an amount from 5.5 wt. % to 6.0 wt. %; and Cu in an amount from 0.30 wt. % to 1.0 wt. %. 
     
     
         16 . The method of  claim 14 , wherein continuously casting comprises a solidification rate of at least 1° C./s to produce the cast product. 
     
     
         17 . The method of  claim 14 , wherein annealing comprises batch annealing or continuous annealing. 
     
     
         18 . The method of  claim 14 , wherein flash homogenizing comprises heating the cast product from 400° C. to 600° C. for less than 10 minutes. 
     
     
         19 . The method of  claim 14 , further comprising paint baking the cold rolled product after annealing to produce an aluminum alloy product. 
     
     
         20 . The method of  claim 19 , wherein the yield strength of the aluminum alloy product increases by 5 MPa or greater after paint baking.