Superplastic behavior of extruded Mg-9RY-4Zn alloy containing long period stacking ordered phase

Superplastic phenomenon is observed in a long period stacking ordered (LPSO) phase strengthened Mg-9RY-4Zn alloy. The maximum elongation of 720% is achieved. The predominant superplastic mechanism is lattice-diffusion-controlled grain boundary sliding (GBS). The alloy fails through cavity coalescence. The unique role of LPSO phase in superplastic deformation is discussed.