Evaluation of specific plastic deformation behavior for LPSO-type magnesium alloy by in-situ neutron diffraction

Morooka, Satoshi  ; Gong, W.; Harjo, S.   ; Aizawa, Kazuya  

Recently, magnesium alloys containing a Mg-Zn-Y long-period stacking ordered (LPSO) phase structure have been reported to exhibit excellent mechanical properties, including high strength and reasonable ductility. It is very important to determine the differences in plastic deformation behaviors, mechanical properties by existing of LPSO phase structure and their origin of deformation mechanism induced by the crystal structures. In this study, the reversible cyclic hardening behavior of LPSO-type magnesium alloys is investigated using TOF neutron diffraction during dynamic tension-compression cyclic loading conditions at constant 0.5 % strain amplitude. The peak stresses in both tension and compression were observed to increase gradually up to the 200th cycle. At the 200th tension-compression cycle, tension and compression peak stresses are approximately +97.4 and -176.7 MPa, respectively. The peak stress for the compression was observed to be larger than that for the tension, suggesting that kinking accompanying with hardening was occurred by compression deformation. The evidence of reversible deformation behavior was obtained from the change in individual () integrated intensity during real-time tension-compression cyclic testing.