Aluminum alloy for die casting and method of manufacturing cast aluminum alloy using the same

Abstract

Disclosed are an aluminum alloy for die casting that has excellent thermal conductivity and corrosion resistance, which can be used for parts requiring heat dissipation and high corrosion resistance, and a method of producing a cast aluminum alloy using the same. Provided is an aluminum alloy for die casting that may include an amount of about 8.5 to 10.5 wt % of silicon (Si); an amount of about 3.6 to 5.5 wt % of magnesium (Mg); an amount of about 0.3 to 1.0 wt % of iron (Fe); an amount of about 0.1 to 1.0 wt % of manganese (Mn); and the balance of aluminum (Al) and inevitable impurities, all the wt % are based on the total weight of the aluminum alloy.

What is claimed is: 
     
         1 . An aluminum alloy for die casting comprising:
 an amount of about 7.8 to 10.5 wt % of silicon (Si);   an amount of about 3.6 to 5.5 wt % of magnesium (Mg);   an amount of about 0.3 to 1.0 wt % of iron (Fe);   an amount of about 0.1 to 1.0 wt % of manganese (Mn); and   a balance of aluminum (Al) and other inevitable impurities,   all wt % are based on the total weight of the aluminum alloy.   
     
     
         2 . The aluminum alloy according to  claim 1 , further comprising an amount of about 0.002 to 0.02 wt % of beryllium (Be). 
     
     
         3 . The aluminum alloy according to  claim 1 , wherein the aluminum alloy comprises an amount of about 8.0 to 10.5 wt % of the silicon (Si). 
     
     
         4 . The aluminum alloy according to  claim 1 , wherein a ratio of Si/Mg is not less than about 1.5 and less than 3.0. 
     
     
         5 . The aluminum alloy according to  claim 1 , wherein a total content of copper (Cu), zinc (Zn) and nickel (Ni) contained as impurities in the aluminum alloy is about 0.2 wt % or less. 
     
     
         6 . The aluminum alloy according to  claim 1 , wherein the aluminum alloy has a yield strength of about 260 MPa or greater. 
     
     
         7 . The aluminum alloy according to  claim 1 , wherein the aluminum alloy has a tensile strength of about 320 MPa or greater. 
     
     
         8 . The aluminum alloy according to  claim 1 , wherein the aluminum alloy has an elongation of about 2.0 to 3.0%. 
     
     
         9 . The aluminum alloy according to  claim 1 , wherein the aluminum alloy has a thermal conductivity of about 135 w/m·K or greater. 
     
     
         10 . The aluminum alloy according to  claim 1 , wherein the aluminum alloy has an electrical conductivity of about 30% IACS or greater. 
     
     
         11 . A method of producing a cast aluminum alloy comprising:
 preparing a molten aluminum (Al) batch by melting aluminum (Al) or an Al scrap to prepare molten Al;   primary heating the prepared molten Al batch;   preparing a primary molten alloy by adjusting a content of Si in the heated molten Al batch to about 7.8 to 10.5 wt % thereby conducting a primary alloying;   secondary heating the primary molten alloy;   preparing a secondary molten alloy by adjusting a content of iron (Fe) in the heated primary molten alloy to about 0.3 to 1.0 wt % and adjusting a content of manganese (Mn) therein to about 0.1 to 1.0 wt % thereby conducting a secondary alloying;   cooling the secondary molten alloy; and   preparing a tertiary molten alloy by adjusting a content of magnesium (Mg) in the cooled secondary molten alloy to about 3.6 to 5.5 wt % thereby conducting a tertiary alloying,   all the wt % based on the total weight of the case aluminum alloy.   
     
     
         12 . The method according to  claim 11 , wherein the primary alloying comprises adjusting the content of Si to about 8.0 to 10.5 wt % to prepare the primary molten alloy. 
     
     
         13 . The method according to  claim 11 , wherein the secondary alloying comprises further adding a content of about 0.002 to 0.02 wt % of beryllium (Be) to the heated primary molten alloy. 
     
     
         14 . The method according to  claim 11 , wherein the primary heating comprises heating the molten Al batch to a first heating temperature of about 800 to 850° C.,
 the secondary heating comprises heating the primary molten alloy to a second temperature of about 900 to 950° C., and 
 the cooling comprises cooling the secondary molten alloy to a third temperature of about 700 to 750° C. 
 
     
     
         15 . The method according to  claim 11 , further comprising casting of injecting the tertiary molten alloy into a mold to produce a cast aluminum alloy. 
     
     
         16 . The method according to  claim 15 , wherein the casting comprises injecting the tertiary molten alloy at a casting temperature of about 680 to 750° C. into a mold for die casting. 
     
     
         17 . A vehicle part comprising an aluminum alloy of  claim 1 .