Effect of Mg Content on the Microstructure and Corrosion Properties of Al-Cu-Mn Alloy

Abstract

In this paper, the effect of Mg content on the microstructure and properties of Al-Cu-Mn alloy was investigated. The microstructures and the mechanical properties of the alloys were studied by scanning electron microscopy and transmission electron microscopy, and Vickers hardness measurement, respectively. Furthermore, the effect of Mg content on the corrosion resistance of the alloys was explored by exfoliation corrosion test, intergranular corrosion test, and electrochemical techniques. The results show that the overall properties of Al-Cu-Mn alloy with 0.1 wt.% Mg are superior to other alloys. Specifically, the Vickers hardness of this alloy reaches 111.45 HV. The grating of exfoliation corrosion is EA, and the intergranular corrosion depth is 30.2 μm. It is believed that the improved mechanical properties and corrosion resistance of the Al-Cu-Mn alloy with 0.1 wt.% Mg result from the S phase formed in the alloy and the highly dispersive distribution of the θ phase.