ADVANCED CAST ALUMINUM ALLOYS FOR AUTOMOTIVE ENGINE APPLICATION WITH SUPERIOR HIGH-TEMPERATURE PROPERTIES

摘要

A high fatigue strength aluminum alloy comprises in weight percent copper 3.0 - 3.5%, iron 0 - 1.3%, magnesium 0.24 - 0.35%, manganese 0 - 0.8%, silicon 6.5 - 12.0%, strontium 0 - 0.025%, titanium 0.05 - 0.2%, vanadium 0.20 - 0.35%, zinc 0 - 3.0%, zirconium 0.2 - 0.4%, a maximum of 0.5% other elements and balance aluminum plus impurities. The alloy defines a microstructure having an aluminum matrix with the Zr and the V in solid solution after solidification. The matrix has solid solution Zr of at least 0.16% after heat treatment and solid solution V of at least 0.20% after heat treatment, and both Cu and Mg are dissolved into the aluminum matrix during the heat treatment and subsequently precipitated during the heat treatment. A process for heat treating an AI-Si-Cu-Mg-Fe-Zn-Mn-Sr-TMs alloy comprises heat treating the alloy to produce a microstructure having a matrix with Zr and V in solid solution after solidification.