US Patent 7435305 Cast aluminum alloy compressor wheel for a turbocharger

A compressor wheel made of a cast aluminum alloy, wherein the cast aluminum alloy contains Cu 1.4 to 3.2 mass %, Mg 1.0 to 2.0 mass %, Ni 0.5 to 2.0 mass %, Fe 0.5 to 2.0 mass %, and at least one selected from the group consisting of Ti 0.01 to 0.35 mass %, Zr 0.01 to 0.30 mass %, Sc 0.01 to 0.8 mass %, and V 0.01 to 0.5 mass %, with the balance being aluminum and inevitable impurities, with the [(Cu content)+0.5×(Mg content)] being 3.8 mass % or less, and with a secondary dendrite arm spacing being 50 μm or less, wherein the cast aluminum alloy is being reinforced by a solution treatment and an aging treatment, and wherein the compressor wheel shows good heat resistant strength, and is for use in a turbocharger.