Effect of Cu content on the microstructure and properties of Al-Mg-Si alloys

Abstract The effects of Cu content on Al-Mg-Si alloys were investigated using OM, SEM, EDS, tensile tests. The increase in copper content will lead to an increase in the content of the second phase in the as cast alloy. When Cu is 0.4 wt%, most of the phases consist of the Mg2Si phase, a few Cu containing phases, and AlFeMnSi. As the Cu content increases to 0.8 wt%, a good many Cu containing phases precipitated. The alloy precipitated of fine AlMnSi, AlMnSiCr, and AlMnSiCu reinforced phases after solution and aging. When Cu is 0.8 wt%, the most strengthening phases and the best comprehensive properties. The yield strength is 270.4 Mpa, tensile strength is 352.4 MPa.