세미나

Taekyung Lee(School of Mechanical Engineering, Pusan National University, Korea)

Multi-pass caliber-rolled Mg alloys possess a unique basal texture with split basal poles that are in contrast to alloys subjected to other plastic deformation processes. The intrinsic nature of texture development allows anisotropic material properties, which are elucidated in this study. Caliber-rolled Mg alloys were compressed along the rolling, transverse, and normal directions, to cause plastic anisotropy. These alloys presented distinct differences in compressive flow behaviors, deformation modes, and twinning characteristics (in terms of fraction, active variant, and propagation). The basal slip isotropically accommodated compressive deformation, whereas the {10–12} extension twinning and prismatic slip exhibited selective activation depending on the loading vector. Such disparities were interpreted in terms of the Schmid factor, in-grain misorientation axes analysis, and geometrical compatibility parameter. In addition, the yield asymmetry of caliber-rolled Mg alloy was investigated as well. Caliber rolling gave rise to nearly symmetric behavior in terms of yielding. These mechanical improvements were interpreted in light of its microstructural characteristics, such as ultrafine-grained structure, dynamic recrystallization, precipitation, basal texture with tilting of c-axes, and activation of mechanical twinning.