Dislocation Behavior and Grain Boundary Segregation of Mg–Zn Alloys

Mg–Zn solid solutions have been reported to show 14–21% tensile elongation after rolling and annealing, but their textures exhibit strong basal texture similar to pure Mg. This phenomenon contrasts with the case in Mg–Y solid solutions showing good RT ductility and weakened basal textures. To reveal the mechanism of the good ductility and strong basal texture of Mg–Zn solid solutions at RT, we investigated the effect of Zn on Mg alloys using atomistic simulations. The simulations show that Zn can activate <c + a> slip by reducing critical resolved shear stress anisotropy among slip systems, thereby improving ductility. It is also found that grain boundary segregation tendency of Zn is low. The grain boundary segregation is known to affect twinning and recrystallization which can modify the texture evolution process. From the low grain boundary segregation of Zn, Mg–Zn alloys are expected to yield a texture similar to that of pure Mg.