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

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.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jan 10, 2022
Source ID
10.1038/s41467-021-27591-z

Entities

People

  • Andrew M. Minor
  • Dalong Zhang
  • Enrique J. Lavernia
  • Irene J Beyerlein
  • Jian Wang
  • Jim Ciston
  • Julie Schoenung
  • Lin Jiang
  • Mingjie Xu
  • Mingyu Gong
  • S. Mahajan
  • Timothy J. Rupert
  • Xiaoqing Pan
  • Xin Wang
  • Yinmin Morris Wang
  • Zhiliang Pan

Organizations

  • National Science Foundation

Tags

Readers

  • Materials Science and Engineering.
  • Systems Analysis and Design

Technology Areas

  • Microelectronics