OS0106 In-situ Neutron Diffraction Study on Tensile Deformation Behaviour of Mg-Zn-Y Alloy Containing of LPSO Phases

Abstract

Tensile deformation behavior of two phase Mg-Zn-Y alloy containing of alpha Mg matrix and 18R long period stacking ordered (LPSO) phase was investigated by in-situ neutron diffractmeter "TAKUMI". Lattice spacing was measured with increase of the applied stress. The internal stress was partitioned into the grain interface between alpha Mg matrix and LPSO phase, which was called as phase stresses. Beyond the onset of plastic flow, micro-yielding, almost no change of the phase strain in magnesium matrix was detected with increase of the applied stress. On the other hand, phase strain in LPSO phase was continuously increased. These results show good agreement with the predictions by a simple two-phase model: the strong LPSO phase yields higher stress than macro-yield stress, resulting in high strengthening of two phase Mg-Zn-Y alloy.