Investigation on Texture Evolution and Recrystallization Aspects of Novel Mg–Zn–Gd–Y–Nd Alloys

Magnesium exhibits substantial property enhancement for a vast range of applications via alloying by rare earth elements (REs). The effect of different amounts of alloying elements (Zn and REs such as Gd, Y and Nd) on the microstructure, texture and mechanical properties of Mg has been investigated here by means of optical microscopy, electron backscattered diffraction, shear punch test and hardness test. Results indicate that the recrystallization process along the grain boundaries consists of dynamic, metadynamic and static recrystallization, while dynamic recrystallization as the dominant mechanism gives rise to bimodal microstructures in as-extruded samples with superior properties. The recrystallized area is narrow at low amounts of alloying elements, whereas addition of higher amounts of alloying elements promotes recrystallization, expands recrystallized areas and weakens texture intensity. Moreover, it is observed that there are some optimal REs ratios promoting a partially recrystallized grain structure which in turn provides higher shear strength, hardness values, and more enhanced ductility as well as a weaker texture.

Texture intensity decreases by the increase in the amount of alloying elements