In-situ neutron diffraction study of deformation behavior of AZ31 alloy at 21K

Gong, W.   ; Harjo, S.   ; 眞山 剛*; 川崎 卓郎   ; 相澤 一也  ; Sun, B.*; 辻 伸泰*

Gong, W.; Harjo, S.; Mayama, Tsuyoshi*; Kawasaki, Takuro; Aizawa, Kazuya; Sun, B.*; Tsuji, Nobuhiro*

We conducted in-situ neutron diffraction experiments to investigate the temperature dependence of deformation mechanisms at 21 K in an AZ31 Mg alloy. The neutron diffraction results demonstrate that the extension twinning was enhanced at cryogenic temperature, which can provide additional capacity for strain accommodation and work hardening. Moreover, the contraction double twinning, as known to be the crack initiation source in Mg alloys, was suppressed at 21 K. The different sensitivity to temperature of various deformation modes is considered to be the reason for the simultaneous increase in strength and ductility of the commercial AZ31 alloy at 21K.