Aluminum alloy products having selectively recrystallized microstructure and methods of making

Abstract

The present disclosure generally provides aluminum alloy products having selectively recrystallized microstructure at one or more surfaces of the product. The disclosure also provides articles of manufacture made from such products, and methods of making such products, such as through casting and rolling. The disclosure also provides various end uses of such products, such as in automotive, transportation, electronics, and industrial applications.

What is claimed is: 
     
         1 . A method of making an aluminum alloy article, the method comprising:
 casting an aluminum alloy to form an aluminum alloy cast product;   homogenizing the aluminum alloy cast product to form a homogenized aluminum alloy cast product;   subjecting the homogenized aluminum alloy cast product to a first rolling process to form a first rolled aluminum alloy product having a first thickness, wherein the first rolling process comprises one or more hot rolling passes followed by one or more cold rolling passes;   annealing the first rolled aluminum alloy product at a temperature of not more than 50° C. above a minimum recrystallization temperature of the aluminum alloy to form a first annealed aluminum alloy product; and   subjecting the first annealed aluminum alloy product to a second rolling process to form a second rolled aluminum alloy product having a second thickness.   
     
     
         2 . The method of  claim 1 , wherein the aluminum alloy is a 5xxx series aluminum alloy, a 6xxx series aluminum alloy, or a 7xxx series aluminum alloy. 
     
     
         3 . The method of  claim 1 , wherein the first thickness is no more than 10 mm. 
     
     
         4 . The method of  claim 1 , wherein the annealing is carried out at the temperature above the minimum recrystallization temperature for no more than 3.0 hours. 
     
     
         5 . The method of  claim 1 , wherein the annealing is carried out at a first temperature above the minimum recrystallization temperature for a first period of time and at a second temperature above the minimum recrystallization temperature for a second period of time, wherein the first temperature above the minimum recrystallization temperature is greater than the second temperature above the minimum recrystallization temperature. 
     
     
         6 . The method of  claim 1 , wherein the second thickness is no more than 4.0 mm. 
     
     
         7 . The method of  claim 1 , wherein the second rolled aluminum alloy product comprises:
 a first surface portion, wherein the first surface portion comprises a first rolled surface, and wherein the first surface portion has a first recrystallization quotient;   a second surface portion opposing the first surface portion, wherein the second surface portion comprises a second rolled surface, and wherein the second surface portion has a second recrystallization quotient; and   an intermediate portion positioned between the first surface portion and the second surface portion, wherein the intermediate portion has a third recrystallization quotient, and wherein the third recrystallization quotient is less than at least one of the first recrystallization quotient or the second recrystallization quotient.   
     
     
         8 . The method of  claim 7 , wherein the first recrystallization quotient is between 0.50 and 1.0, wherein the second recrystallization quotient is between 0.50 and 1.0, or wherein the third recrystallization quotient is between 0.01 and 0.65. 
     
     
         9 . The method of  claim 7 , wherein the first surface portion extends from a first surface of the first surface portion to a first depth less than 40% of a thickness of the second rolled aluminum alloy product, and wherein the second surface portion extends from a second surface of the second surface portion to a second depth less than 40% of the thickness of the second rolled aluminum alloy product. 
     
     
         10 . An aluminum alloy article comprising an aluminum alloy material, the aluminum alloy material comprising:
 a first surface portion, wherein the first surface portion comprises a first rolled surface, and wherein the first surface portion has a first recrystallization quotient;   a second surface portion opposing the first surface portion, wherein the second surface portion comprises a second rolled surface, and wherein the second surface portion has a second recrystallization quotient; and   an intermediate portion positioned between the first surface portion and the second surface portion, wherein the intermediate portion has a third recrystallization quotient, and wherein the third recrystallization quotient is less than at least one of the first recrystallization quotient or the second recrystallization quotient.   
     
     
         11 . The aluminum alloy article of  claim 10 , wherein the aluminum alloy material is a 5xxx series aluminum alloy, a 6xxx series aluminum alloy, or a 7xxx series aluminum alloy. 
     
     
         12 . The aluminum alloy article of  claim 10 , wherein one or both of the first rolled surface or the second rolled surface is formed by a process that comprises cold rolling. 
     
     
         13 . The aluminum alloy article of  claim 10 , wherein the first surface portion extends from a surface of the first surface portion to first a depth of no more than 40.0% of a thickness of the aluminum alloy article. 
     
     
         14 . The aluminum alloy article of  claim 13 , wherein the second surface portion extends from a surface of the second surface portion to a second depth of no more than 40.0% of the thickness of the aluminum alloy article. 
     
     
         15 . The aluminum alloy article of  claim 10 , wherein the intermediate portion extends from a first depth of the first surface portion to a second depth of the second surface portion. 
     
     
         16 . The aluminum alloy article of  claim 10 , wherein the first surface portion has a first recrystallization quotient, wherein the second surface portion has a second recrystallization quotient, wherein the intermediate portion has a third recrystallization quotient, and wherein the third recrystallization quotient is less than at least one of the first recrystallization quotient or the second recrystallization quotient, wherein a recrystallization quotient corresponds to a percentage or fractional amount, volume, or mass of a portion of the aluminum alloy material that is recrystallized as compared to a total amount, volume, or mass of the portion of the aluminum alloy material. 
     
     
         17 . The aluminum alloy article of  claim 16 , wherein the first recrystallization quotient is at least 0.50, wherein the second recrystallization quotient is at least 0.50, or wherein the third recrystallization quotient is no more than 0.65. 
     
     
         18 . The aluminum alloy article of  claim 10 , having a β angle of between 100° and 138° for bendability testing according to Specification VDA 238-100. 
     
     
         19 . The aluminum alloy article of  claim 10 , having an exfoliation corrosion rating of EA for exfoliation corrosion testing according to ASTM Test No. G34-01. 
     
     
         20 . The aluminum alloy article of  claim 10 , wherein the first surface portion extends from a first surface of the first surface portion to a first depth less than 40% of a thickness of the aluminum alloy article, and wherein the second surface portion extends from a second surface of the second surface portion to a second depth less than 40% of the thickness of the aluminum alloy article.