High-strength aluminum alloy for die casting having excellent corrosion resistance and thermal conductivity, method for producing the same, and method for producing aluminum alloy casting using the same

Abstract

A high-strength aluminum alloy for die casting having excellent corrosion resistance and thermal conductivity includes, based on the total weight of the alloy, 5 to 7 wt % of silicon (Si), 0.1 to 1.0 wt % of iron (Fe), 0.1 to 3.0 wt % of magnesium (Mg), 0.1 to 1.0 wt % of nickel (Ni), 0.15 to 0.45 wt % of titanium (Ti), 1.0 to 3.0 wt % of tin (Sn), and the remainder aluminum (Al).

We claim: 
     
         1 . high-strength aluminum alloy for die casting having excellent corrosion resistance and thermal conductivity, which. comprises, based on the total weight of the alloy, 5 to 7 wt % of silicon (Si), 0.1 to 1.0 wt % of iron (Fe), 0.1 to 3.0 wt % of magnesium (Mg), 0.1 to 1 wt % of nickel (Ni), 0.15 to 0.45 wt % of titanium (Ti), 1.0 to 3.0 wt % of tin (Sn), and the remainder aluminum (Al), 
     
     
         2 . The high-strength aluminum alloy of  claim 1 , which has a tensile strength of 300 to 320 MPa and a thermal conductivity of 140 to 160 w/m·K. 
     
     
         3 . A method for producing a high-strength aluminum alloy for die casting having excellent corrosion resistance and thermal conductivity, the method comprising:
 a first step of preparing materials comprising, based on the total weight of the materials, 5 to 7 wt % of silicon (Si), 0.1 to 1.0 wt % of iron (Fe), 1.0 to 3.0 wt % of magnesium (Mg), 0.1 to 1.0 wt % of nickel (Ni), 0.15 to 0.45 wt % of titanium (Ti), 1.0 to 3.0 wt % of tin (S), and the remainder aluminum (Al);   a second step of melting the prepared aluminum (Al) by heating to temperature of 700 to 750° C., followed by heating to a temperature of 800 to 250° C.;   a third step of adding the silicon (Si) to a melt resulting from the second step, followed by heating to a temperature of 900 to 1000° C.;   a fourth step of adding the iron (Fe), nickel (Ni) and titanium (Ti) to a mixture resulting from the third step, and then heating the mixture for 4 to 5 hours;   a fifth step of reducing the temperature of the mixture of the fourth step to a temperature of 700 to 750° C., and then adding the magnesium (Mg) and tin (Sn) to the mixture, followed by melting; and   a sixth step of removing impurities from the mixture of the fifth step, and then tapping the mixture as an ingot, thereby producing the alloy.   
     
     
         4 . The method of  claim 3 , wherein the second to sixth steps further comprise analyzing and correcting components of the mixture. 
     
     
         5 . The method of  claim 3 , wherein the sixth step comprises floating the impurities by bubbling an argon or nitrogen gas injected through a bottom of the mixture, and removing the impurities floated on a surface of the mixture. 
     
     
         6 . The method of  claim 3 , wherein the sixth step further comprises filtering the impurities in a tapping outlet and a tapping channel during tapping of the mixture. 
     
     
         7 . A method for producing a high-strength aluminum alloy casting having excellent corrosion resistance and thermal conductivity by die, casting, the method comprising the steps of:
 preparing an alloy comprising, based on the total weight of the alloy, 5 to 7 wt % of silicon (Si), 0.1 to 1.0 wt % of iron (Fe), 0.1 to 3.0 wt % of magnesium (Mg), 0.1 to 1.0 wt % of nickel (Ni), 0.15 to 0.45 wt % of titanium (Ti), 1.0 to 3.0 wt % of tin (Sn), and the remainder aluminum (Al); and   melting the alloy, and pouring the melted alloy into a die casting mold, thereby producing the casting.   
     
     
         8 . The method of claim wherein the produced casting is an electronic device part or an automotive part. 
     
     
         9 . The method of  claim 8 , wherein the casting has a thickness (T) of 0.38 mm or less.