Corrosion resistance of ultrafine-grained Zn-1%Li-2%Mg and Zn-1.0%Mg-1.0%Fe alloys

Abstract

The paper studies the corrosion resistance of ultrafine-grained (UFG) Zn-1%Li-2%Mg and Zn-1%Mg-1%Fe alloys having unique mechanical properties due to severe plastic deformation. The X‑ray diffraction analysis and scanning electron microscopy are used to explore the alloy surface after the interaction with a corrosive environment. It is found that the corrosion rate of UFG Zn-1%Li-2%Mg and Zn-1%Mg-1%Fe alloys is 0.089 and 0.061 mm/year, respectively. For the Zn-1%Li-2%Mg alloy, this is explained by the higher content of a mixture of Zn and Mg₂Zn₁₁ phases and the defect structure of the Zn phase. The growth in the corrosion rate in Zn-1%Mg-1%Fe alloy, can be explained by the higher content of impurity atoms in the Zn phase, leading to a higher corrosion potential.