Effect of solid solution Zn atoms on corrosion behaviors of Mg-2Nd-2Zn alloys

The effects of heat treatments on the microstructures and corrosion behaviors of extruded Mg-2Nd-2Zn alloys in 3.5% NaCl electrolyte were investigated. It was found that the average corrosion rate of solid solution Mg-2Nd-2Zn alloy is 45.86 mm/y, which is much lower than that of the as-extruded and solution-aged Mg alloys. The nano-scale oxides were formed by the oxidation of solid solution atoms during the corrosion process and filled into the porous corrosion product film, which was conducive to reducing the corrosion rates of Mg alloys. Therefore, the solid solution treatment remarkably improved the corrosion rate of Mg alloys.