Revealing the weak work-hardening behavior in aged Mg-RE alloys: A synchrotron radiation diffraction study

Magnesium (Mg) alloys with rare-earth (RE) elements have received increasing attention as the lightest structural materials. However, they often present a weak work-hardening behavior after aging treatment, with the reason behind remaining unclear. In this work, in situ tensile tests combined with synchrotron radiation diffraction technique were utilized to investigate the evolution of basal and non-basal dislocations in two aged Mg alloys with different volume fractions of beta 1 precipitates. The results of standard Williamson-Hall (W-H) analysis indicated that more basal dislocations were activated at higher stress. This work emphasized that the underwhelming work-hardening was correlated to the synergy of high-density basal dislocations and relatively low-density non-basal dislocations during deformation. (c) 2023 Elsevier B.V. All rights reserved.