Tension-compression asymmetry of an AM magnesium alloy unveiled by in-situ synchrotron X-ray diffraction

作者：Hao Chen, Huicong Chen, Yuanding Huang, Weimin Gan, Emad Maawad, Weidong Xie, Guobing Wei, Yan Yang, Yu Zou · 发表于：Journal of Magnesium and Alloys · 年份：2025 · DOI：10.1016/j.jma.2025.10.008 · 被引用次数：2 · 研究领域：Magnesium Alloys: Properties and Applications、Aluminum Alloys Composites Properties、Advanced Welding Techniques Analysis

• This study systematically compares the deformation modes during both tension and compression in magnesium alloys using in situ synchrotron X-ray diffraction. • Extrusion texture governs slip and twinning activity, leading to pronounced tension-compression asymmetry. • In situ measurements reveal the evolution of dislocation density and twin volume fraction during deformation. • Both tension and compression activate dislocations, with slip dominating in tension and tensile twinning initiating deformation in compression before slip takes over at later stages. • Strain hardening during compression is mainly driven by twin boundary formation and dislocation multiplication, with twinning dominating at later stages. Magnesium (Mg) alloys typically exhibit anisotropic mechanical behaviors due to their hexagonal close-packed (hcp) crystal structures, often leading to tension-compression asymmetries. Understanding of the asymmetrical and related deformation mechanisms is crucial for their structural applications, particularly in the lightweight transportation industries. Nevertheless, the underlying deformation mechanisms (e.g., slip versus twinning) at each deformation stage during tension and compression have not been fully understood. In this study, we employed tensile and compressive tests on extruded Al and Mn containing Mg alloy, i.e., an AM alloy Mg-0.6Mn-0.5Al-0.5Zn-0.4Ca, during the synchrotron X-ray diffraction. Our results show that distinct deformation behaviors and mech...