Deformation mechanisms of AZ31 magnesium alloy at 21K revealed by in-situ neutron diffraction

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

Mg and its alloys possess great potential for a wide range of applications, particularly in cryogenic applications. However, the deformation mechanisms of Mg alloys at cryogenic temperatures are not fully understood due to the absence of appropriate methods. In this study, we investigated the deformation behavior of a commercial AZ31 alloy at cryogenic temperatures using in-situ neutron diffraction. The yield stress of AZ31 alloy significantly increased with decreasing temperature in tensile deformation, but slightly increased in compressive deformation. Interestingly, both the fracture strain and stress at 20 K exhibited a substantial increase compared to 298 K in compressive deformation. In-situ neutron diffraction experiments were conducted using the engineering diffractometer TAKUMI at J-PARC to reveal the deformation mechanisms in the AZ31 alloy at cryogenic temperatures. The stress-strain response of the AZ31 alloy with temperature will be discussed in relation to the temperature-dependent activity of deformation mechanisms.