Optimising the mechanical properties and corrosion resistance of biodegradable Mg-2Zn-0.5Nd alloy by solution treatment

Mechanical properties and corrosion resistance are important performance parameters for the application of biodegradable magnesium alloy. In this study, Mg-2Zn-0.5Nd alloy with different microstructures was achieved by solid solution treatment to study the effect of grain size and the second phase on its corrosion resistance and tensile properties. The results indicated that the corrosion resistance and elongation were significantly increased when the alloy was solution treated from 425 ℃ to 450 ℃, the lowest corrosion current density of 1.31 μA·cm-2 was obtained when solution treated at 425 ℃. The optimal elongation was achieved at the solution treated temperature of 450 ℃, which was principally due to the influence of second phases dissolution. Moreover, it was also observed that the grain refinement appreciably improved ultimate tensile strength and corrosion resistance of the alloy, while the reduction of the second phase improved the elongation of the alloy.