Multi-scale characterization of twinning and detwinning in AZ31 alloy

AZ31マグネシウム合金の変形双晶の形成と消滅のマルチスケール観察

Gong, W.   ; Zheng, R.*; Harjo, S.   ; 川崎 卓郎   ; 相澤 一也  ; 辻 伸泰*

Gong, W.; Zheng, R.*; Harjo, S.; Kawasaki, Takuro; Aizawa, Kazuya; Tsuji, Nobuhiro*

Extension twinning and detwinning play crucial roles in cyclic loading deformation of magnesium (Mg) and its alloys. The occurrences of twining and detwinning are accompanied by the motion of twin boundaries (TBs), and then the interaction between the TBs and lattice defects such as dislocations and various boundaries is the key factor for the mechanical properties. Because of the complex microstructures introduced by cyclic deformation, the work hardening mechanisms associated with twinning and detwinning in Mg alloys are still far from being understood. In the present study, twinning and detwinning behavior of a commercial AZ31 Mg alloy during cyclic compression-tension deformation was evaluated in multi-scale using in-situ neutron diffraction (ND), identical area electron backscatter diffraction (EBSD), and transmission electron microscopy techniques. The relationship between the mechanical responses in cyclic deformation and microstructures was investigated.