Microstructure, mechanical and corrosion properties of accumulative roll bonded Mg-2%Zn/anodized Al-7075 composite

Abstract

Multilayered composite of Mg-2%Zn/anodized Al-7075 was developed by accumulative roll bonding (ARB) of wrought Mg-2%Zn and anodized aluminium 7075 alloy. The Mg-2%Zn/anodized Al-7075 composite exhibited density of 2298 kg/m3 which is about 1.2 times lighter weight as compared to Al-7075 alloy. The electron backscatter diffraction (EBSD), transmission electron microscopy (TEM) showed an average grain size of 1 ?m and 0.73 ?m in Mg-2%Zn and anodized Al-7075 layers respectively, and with high angle grain boundaries (HAGBs). Mechanical properties were evaluated by microhardness and tensile tests and found significant improvement in strength and hardness values as compared with Mg-2%Zn alloy after four pass ARB process. The multilayered composite shows better corrosion resistance as compared to rolled Mg-2%Zn alloy evaluated using using potentiodynamic polarization test. � 2017 Elsevier Ltd.