Three-dimensional nucleation and growth of deformation twins in magnesium

Lee, Sangwon [Univ. of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000232611813); Pilipchuk, Michael [Univ. of Michigan, Ann Arbor, MI (United States)] (ORCID:0009000198883280); Yildirim, Can [European Synchrotron Radiation Facility (ESRF), Grenoble (France)] (ORCID:0000000249690685); Greeley, Duncan [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:000000018946313X); Shi, Qianying [Univ. of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000184169345); Berman, Tracy D. [Univ. of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000340275992); Creuziger, Adam [National Inst. of Standards and Technology (NIST), Gaithersburg, MD (United States)] (ORCID:0000000197722066); Rust, Evan [National Inst. of Standards and Technology (NIST), Gaithersburg, MD (United States)]; Detlefs, Carsten [European Synchrotron Radiation Facility (ESRF), Grenoble (France)] (ORCID:0000000325732286); Sundararaghavan, Veera [Univ. of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000212137958); Allison, John E. [Univ. of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000163196416); Bucsek, Ashley [Univ. of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000325607135)

doi:10.1126/science.adv3460

DOE OSTI · 2935370

Three-dimensional nucleation and growth of deformation twins in magnesium

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Abstract

At two-thirds the weight of aluminum, magnesium alloys have the potential to reduce the fuel consumption of transportation vehicles. These advancements depend on our ability to optimize the desirable versus undesirable effects of deformation twins, which are three-dimensional (3D) microstructural domains that form under mechanical stresses. Previously only characterized through surface or thin-film measurements, we here present 3D in situ characterization of deformation twinning inside an embedded grain over mesoscopic fields of view using dark-field x-ray microscopy supported by crystal plasticity finite element analysis. The results revealed the role of triple junctions on twin nucleation and the sequence and irregularity of twin growth and showed that twin-grain junctions, twin-twin junctions, and twin boundaries were the sites of localized dislocation accumulation.

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Lee, Sangwon [Univ. of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000232611813), Pilipchuk, Michael [Univ. of Michigan, Ann Arbor, MI (United States)] (ORCID:0009000198883280), Yildirim, Can [European Synchrotron Radiation Facility (ESRF), Grenoble (France)] (ORCID:0000000249690685), Greeley, Duncan [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:000000018946313X), Shi, Qianying [Univ. of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000184169345), Berman, Tracy D. [Univ. of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000340275992), Creuziger, Adam [National Inst. of Standards and Technology (NIST), Gaithersburg, MD (United States)] (ORCID:0000000197722066), Rust, Evan [National Inst. of Standards and Technology (NIST), Gaithersburg, MD (United States)], Detlefs, Carsten [European Synchrotron Radiation Facility (ESRF), Grenoble (France)] (ORCID:0000000325732286), Sundararaghavan, Veera [Univ. of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000212137958), Allison, John E. [Univ. of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000163196416), Bucsek, Ashley [Univ. of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000325607135). 2025-08-07. Three-dimensional nucleation and growth of deformation twins in magnesium. https://doi.org/10.1126/science.adv3460

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