Alloy for die-cast vehicle parts and method for manufacturing the same

Abstract

An alloy for die-cast vehicle parts and a method for manufacturing the alloy are provided. The alloy includes aluminum as a main component; magnesium in an amount of about 8.0 to 10.5 wt % based on the total weight of the alloy composition; silicon in an amount of about 1.9 to 3.4 wt % based on the total weight of the alloy composition; copper in an amount of about 0.4 to 2.0 wt % based on the total weight of the alloy composition; manganese in an amount of about 0.3 to 1.0 wt % based on the total weight of the alloy composition; beryllium (Be) at a maximum of about 50 ppm, and other essential impurities. Further, during the manufacturing process, a molten metal is heated to a temperature of about 670 to 730° C. and is injected into a die at a speed of about 3.0 m/s or greater.

What is claimed is: 
     
         1 . An alloy for die-cast vehicle parts, comprising:
 aluminum (Al) as a main component;   magnesium (Mg) in an amount of about 8.0 to 10.5 wt % based on the total weight of the alloy composition;   silicon (Si) in an amount of about 1.9 to 3.4 wt % based on the total weight of the alloy composition;   copper (Cu) in an amount of about 0.4 to 2.0 wt % based on the total weight of the alloy composition;   manganese (Mn) in an amount of about 0.3 to 1.0 wt % based on the total weight of the alloy composition;   a maximum of about 50 ppm of beryllium (Be); and   other essential impurities,   wherein a weight ratio of Mg to Si (Mg/Si) ranges from about 3.1 to about 4.3.   
     
     
         2 . The alloy of  claim 1 , wherein a generation amount of Al—Mg—Cu-based intermetallic compound is equal to or greater than about 7.0%. 
     
     
         3 . The alloy of  claim 1 , wherein a tensile strength is equal to or greater than about 300 MPa and a yield strength is equal to or greater than about 170 MPa. 
     
     
         4 . The alloy of  claim 1 , wherein an Al—Mg—Cu-based intermetallic compound which is a main strengthening phase is dispersedly distributed in an aluminum matrix, along with Mg 2 Si particles. 
     
     
         5 . The alloy of  claim 4 , wherein a size of the Mg 2 Si particle is from about 10 to about 30 μm. 
     
     
         6 . The alloy of  claim 1 , consisting essentially of:
 aluminum (Al) as a main component;   magnesium (Mg) in an amount of about 8.0 to 10.5 wt % based on the total weight of the alloy composition;   silicon (Si) in an amount of about 1.9 to 3.4 wt % based on the total weight of the alloy composition;   copper (Cu) in an amount of about 0.4 to 2.0 wt % based on the total weight of the alloy composition;   manganese (Mn) in an amount of about 0.3 to 1.0 wt % based on the total weight of the alloy composition; and   a maximum of about 50 ppm of beryllium (Be).   
     
     
         7 . A method for manufacturing an alloy for die-cast vehicle parts, wherein the alloy comprises: aluminum (Al) as a main component; magnesium (Mg) in an amount of about 8.0 to 10.5 wt % based on the total weight of the alloy composition; silicon (Si) in an amount of about 1.9 to 3.4 wt % based on the total weight of the alloy composition; copper (Cu) in an amount of about 0.4 to 2.0 wt % based on the total weight of the alloy composition; manganese (Mn) in an amount of about 0.3 to 1.0 wt % based on the total weight of the alloy composition; beryllium (Be) at a maximum of about 50 ppm, and other essential impurities, and a molten metal in which Mg/Si ranges from about 3.1 to about 4.3 is heated to a temperature of about 670 to 730° C. and is injected into a die at a speed of about 3.0 m/s or greater. 
     
     
         8 . A die-cast vehicle part that comprises an alloy of  claim 1 .