Revealing distinct corrosion mechanisms of soluble as-extruded Mg–Er–Ni alloy with LPSO and Mg2Ni phase in different orientations

The effects of Er and Ni content on the microstructure evolution, corrosion mechanism of Mg–Er–Ni alloys with different orientations were investigated. With the increase of Er and Ni content, the corrosion rate of extrusion direction (ED) increases, while transverse direction (TD) is reversed, which may be due to the distinct corrosion mechanism in different orientations, where ED and TD exhibit soluble and corrosion-resistant mechanism, respectively. Moreover, high content second phase alloy with a large deformation grain fraction and low levels second phase alloy with fully recrystallized grains have larger and smaller corrosion rate differences in ED and TD, respectively.