Visualization and validation of twin nucleation and early-stage growth in magnesium

Authors

• Lin Jiang, University of California-Irvine, Thermo Fisher Scientific
• Mingyu Gong, Shanghai Jiao Tong University
• Jian Wang, University of Nebraska-LincolnFollow
• Zhiliang Pan
• Xin Wang, University of California, Irvine
• Dalong Zhang, University of California, Irvine
• Y. Morris Wang, University of Nebraska-Lincoln
• Jim Ciston, Lawrence Berkeley National Laboratory
• Andrew M. Minor, Lawrence Berkeley National Laboratory, University of California-Berkeley
• Mingjie Xu, University of California, Irvine
• Xiaoqing Pan, University of California, Irvine
• Timothy J. Rupert, University of California, Irvine
• Subhash Mahajan, University of California, Davis
• Enrique J. Lavernia, National Academy of Engineering
• Irene J. Beyerlein, University of California, Santa Barbara
• Julie M. Schoenung, University of California, Irvine

Document Type

Article

Date of this Version

2022

Citation

NATURE COMMUNICATIONS | (2022) 13:20 | https://doi.org/10.1038/s41467-021-27591-z | www.nature.com/naturecommunications

Comments

Open access

Abstract

The abrupt occurrence of twinning when Mg is deformed leads to a highly anisotropic response, making it too unreliable for structural use and too unpredictable for observation. Here, we describe an in-situ transmission electron microscopy experiment on Mg crystals with strategically designed geometries for visualization of a long-proposed but unverified twinning mechanism. Combining with atomistic simulations and topological analysis, we conclude that twin nucleation occurs through a pure-shuffle mechanism that requires prismatic-basal transformations. Also, we verified a crystal geometry dependent twin growth mechanism, that is the early-stage growth associated with instability of plasticity flow, which can be dominated either by slower movement of prismatic-basal boundary steps, or by faster glide-shuffle along the twinning plane. The fundamental understanding of twinning provides a pathway to understand deformation from a scientific standpoint and the microstructure design principles to engineer metals with enhanced behavior from a technological standpoint.