al-si-mg-zn-cu alloy for aerospace and automotive castings

Abstract

The present invention provides an aluminum casting alloy with a composition including 4%-9% Si; 0.1%-0.7% Mg; less than or equal to 5% Zn; less than 0.15% Fe; less than 4% Cu; less than 0.3% Mn; less than 0.05% B; less than 0.15% Ti; and the remainder consisting essentially of aluminum. The inventive AlSiMg composition provides increased mechanical properties (Tensile Yield Strength and Ultimate Tensile Strength) in comparison to similiarly prepared E357 alloy at room temperature and high temperature. The present invention also includes a shaped casting formed from the inventive composition and a method of forming a shaped casting from the inventive composition.

1 - 21 . (canceled) 
   
   
       22 . An aluminum casting alloy consisting essentially of, in weight percent:
 about 9% Si;   about 1 wt. % Cu;   about 0.1% to about 0.7% Mg;   less than about 0.15% Fe;   less than about 0.3% Mn;   less than about 0.05% B; and   less than about 0.15% Ti, the balance being essentially aluminum, incidental elements and impurities.   
   
   
       23 . The aluminum casting alloy of  claim 22 , containing about 0.6 wt. % Mg. 
   
   
       24 . An aluminum casting alloy consisting essentially of, in weight percent:
 about 9% Si;   about 2 wt. % Cu;   about 0.1% to about 0.7% Mg;   less than about 0.15% Fe;   less than about 0.3% Mn;   less than about 0.05% B; and   less than about 0.15% Ti, the balance being essentially aluminum, incidental elements and impurities.   
   
   
       25 . The aluminum casting alloy of  claim 22 , containing about 0.6 wt. % Mg.