Aluminum die casting alloy

Abstract

The thermal conductivity of the alloy of the invention can achieve 146 W/m·K, an increase of 45% compared with that of common aluminum die casting alloy-ADC12. The casting defects like shrinkage cavity, micro-porosity and amount of dross also become much less than those of pure aluminum. Further, the fluidity and mold erosion resistance of this alloy is also better than that of pure aluminum and almost equivalent to that of ADC12. When the aluminum die casting alloy of the invention is applied to a heat sink, the thermal resistance is even lower than that of ADC12 and 1070 pure aluminum.

What is claimed is:  
     
         1 . An aluminum die casting alloy comprising 80-90 wt % of aluminum, 9.1-12 wt % of silicon, 4.3-8 wt % of copper, less than 0.3 wt % of magnesium, 0.5-1.2 wt % of iron, less than 1.0 wt % of zinc, and less than 0.9 wt % of manganese.  
     
     
         2 . The aluminum die casting alloy as claimed in    claim 1    further comprising less than 0.1 wt % of nickel, less than 0.1 wt % of chromium, less than 0.1 wt % of lead, less than 0.1 wt % of tin, less than 0.1 wt % of titanium, and less than 0.1 wt % of strontium.  
     
     
         3 . The aluminum die casting alloy useful for a heat sink comprising 80-90 wt % of aluminum, 9.1-12 wt % of silicon, 4.3-8 wt % of copper, less than 0.3 wt % of magnesium, 0.5-1.2 wt % of iron, less than 1.0 wt % of zinc, and less than 0.9 wt % of manganese.  
     
     
         4 . The aluminum die casting alloy useful for a heat sink as claimed in    claim 3    further comprising less than 0.1 wt % of nickel, less than 0.1 wt % of chromium, less than 0.1 wt % of lead, less than 0.1 wt % of tin, less than 0.1 wt % of titanium, and less than 0.1 wt % of strontium.  
     
     
         5 . The aluminum die casting alloy useful for a heat sink as claimed in    claim 3   , wherein said heat sink is applied to CPUs, DRAMs, BGAs, or chipsets.