Aluminum alloy with improved strength and ductility

Abstract

The present disclosure concerns an aluminum alloy with improved strength and ductility. The aluminum alloy composition achieves a superior strength/ductility combination compared to existing Al—Mg—Si alloys. The aluminum alloy may be particularly suitable for applications requiring a yield strength of more than 240 MPa. The aluminum alloy comprises, in weight percent: 0.41-0.59 Si; ≤0.3 Fe; 0.08 to 0.30 Cu; 0.45 to 0.55 Mg; 0.08 to 0.20 Mn; and the balance being aluminum and inevitable impurities. The Mn can be replaced in the aluminum alloy by Cr to an equivalence of Mn and Cr at a ratio Mn=1.6Cr, wherein Mn+1.6Cr+Cu≥0.25.

1 . An aluminum alloy comprising, in weight percent: 
       
         
           
             
               
                 0.41 
                 - 
                 
                   0.59 
                       
                   Si 
                 
               
               ; 
             
           
         
         
           
             
               
                 ≤0.3 
                     
                 Fe 
               
               ; 
             
           
         
         
           
             
               
                 0.08 
                 - 
                 
                   0.3 
                       
                   Cu 
                 
               
               ; 
             
           
         
         
           
             
               
                 0.45 
                 - 
                 
                   0.55 
                       
                   Mg 
                 
               
               ; 
             
           
         
         
           
             
               
                 0.08 
                     
                 to 
                     
                 0.2 
                     
                 Mn 
               
               ; 
             
           
         
       
       or Mn being replaced by Cr to an equivalence of Mn and Cr at a ratio Mn=1.6Cr, wherein Mn+1.6Cr+Cu≥0.25; and
 the balance being aluminum and inevitable impurities. 
 
     
     
         2 . The aluminum alloy of  claim 1 , wherein the alloy comprises 0.08 to 0.20 Mn. 
     
     
         3 . The aluminum alloy of  claim 1 , wherein Mn being replaced by Cr to an equivalence of Mn and Cr at a ratio Mn=1.6Cr in the alloy. 
     
     
         4 . The aluminum alloy of  claim 1 , wherein the inevitable impurities comprise less than 0.1 wt. % of the aluminum alloy and each inevitable impurity is present at a maximum of 0.05 wt. %. 
     
     
         5 . The aluminum alloy of  claim 1 , wherein the inevitable impurities comprise ≤0.05 wt. % Ni. 
     
     
         6 . The aluminum alloy of  claim 1 , wherein the inevitable impurities comprise ≤0.05 wt. % Zn. 
     
     
         7 . The aluminum alloy of  claim 1 , wherein the inevitable impurities comprise ≤0.05 wt. % Ti. 
     
     
         8 . The aluminum alloy of  claim 1 , wherein the inevitable impurities comprise ≤0.05 wt. % B. 
     
     
         9 . The aluminum alloy of  claim 1 , wherein the inevitable impurities comprise ≤0.05 wt. % V. 
     
     
         10 . The aluminum alloy of  claim 1 , comprising 0.43-0.55 wt. % Si. 
     
     
         11 . The aluminum alloy of  claim 1 , comprising ≤0.25 wt. % Fe. 
     
     
         12 . The aluminum alloy of  claim 1 , comprising 0.10-0.30 wt. % Cu. 
     
     
         13 . The aluminum alloy of  claim 1 , comprising 0.47-0.53 wt. % Mg. 
     
     
         14 . The aluminum alloy of  claim 1 , comprising 0.10-0.20 wt. % Mn. 
     
     
         15 . The aluminum alloy of  claim 1 , comprising at least 0.10 wt. % Fe. 
     
     
         16 . The aluminum alloy of  claim 1 , comprising up to 0.10 wt. % Cr. 
     
     
         17 . The aluminum alloy of  claim 1 , further comprising a grain refiner. 
     
     
         18 . An aluminum product comprising the aluminum alloy of  claim 1 . 
     
     
         19 - 20 . (canceled) 
     
     
         21 . The aluminum product of  claim 18  being an automotive part. 
     
     
         22 . A process for making an aluminum product comprising the steps of:
 a. casting the aluminum alloy of  claim 1  to produce a cast aluminum product;   b. extruding the cast aluminum product producing an extruded aluminum product; and   c. cooling the extruded aluminum product.   
     
     
         23 - 27 . (canceled)