12th International Conference on Magnesium Alloys and their Applications (Mg 2021): Deformation
Program Organizers: Alan Luo, Ohio State University; Mihriban Pekguleryuz, McGill University; Sean Agnew, University of Virginia; John Allison, University of Michigan; Karl Kainer; Eric Nyberg, Kaiser Aluminum Trentwood; Warren Poole, University of British Columbia; Kumar Sadayappan, CanmetMATERIALS; Bruce Williams, Canmetmaterials Natural Resources Canada; Stephen Yue, Mcgill University
Friday 9:50 AM
June 18, 2021
Room: Invited III
Location: Virtual
Session Chair: Maria Teresa Perez Prado, Imdea Materials Institute (G 84908953)
9:50 AM Invited
Effect of Phase Morphology on Microscopic Deformation Behavior of Mg-Li-Gd Dual-phase Alloys: Jing Li1; Li Jin1; Jie Dong1; Wenjiang Ding1; 1Shanghai Jiao Tong University
Three dual-phase Mg-6Li-2Gd, Mg-7Li-2Gd and Mg-8Li-2Gd (wt.%) alloys, with different morphology of β-Li and α-Mg phases, were fabricated by hot extrusion and then in-situ tension tested at room temperature (RT). Digital image correlation (DIC) technique and slip trace analysis were utilized to investigate the effect of phase morphology, including the size and configuration of β-Li and α-Mg phases, on the microscopic deformation behavior of Mg-Li-Gd dual-phase alloys. The small α-Mg phase enclosed in a three-dimensional continuously connected network of β-Li phase in Mg-8Li-2Gd (wt.%) alloys was observed to be distributed homogeneously by fine slip traces and triggered a large amount of deformation. The different microscopic deformation behaviors were thus discussed.
10:20 AM Invited
Quantification of Cyclic Twinning-detwinning Behavior During Low-cycle Fatigue of Unalloyed Mg and a Mg-Al Alloy Using High Energy X-ray Diffraction: Aeriel Murphy-Leonard1; Darren Pagan2; Armand Beaudoin3; Matthew Miller4; John Allison5; 1Ohio State University; 2Pennsylvania State University; 3University of Illinois-Urbana Champaign; 4Cornell University; 5University of Michigan
The cyclic twinning and detwinning behavior of unalloyed Mg and a Mg-Al alloy was investigated using in-situ high energy X-ray diffraction (HEXD) under displacement controlled, fully-reversed low cycle fatigue conditions. Measurements were conducted at three levels of applied strain. At strain amplitudes greater than 0.5%, tension-compression asymmetry was observed during cyclic loading and related to cyclic twinning and detwinning. The twinning and detwinning behavior were characterized by monitoring the evolution of X-ray diffraction peaks associated with the basal {0002} planes throughout selected cycle. At strains greater than 0.5%, in-situ HEXD results show that twinning occurs during the compression portion of the cycle and, at early stages of fatigue, most twins are detwinned under reversed loading during the tensile portion of the cycle. After a number of fatigue cycles, the detwinning process was observed to be incomplete and residual twins remained throughout an entire cycle.