Abstract

Deformation twins are three-dimensional domains, traditionally viewed as ellipsoids because of their two-dimensional lenticular sections. In this work, we performed statistical analysis of twin shapes viewing along three orthogonal directions: the ‘dark side’ (DS) view along the twin shear direction (η1), the twinning plane normal (TPN) view (k1) and the ‘bright side’ (BS) view along the direction λ(=k1 × η1). Our electron back-scatter diffraction results show that twins in the DS and BS views normally exhibit a lenticular shape, whereas they show an irregular shape in the TPN view. Moreover, the findings in the TPN view revealed that twins grow faster along λ the lateral direction than along η1 the forward propagation direction at the initial stages of twin growth. These twin sections are irregular, indicating that growth is locally controlled and the overall shape is not perfectly ellipsoidal. We explain these findings using atomistic models, and ascribe them to differences in the mobility of the edge and screw components of the twinning dislocations.

Details

Title
Three-dimensional character of the deformation twin in magnesium
Author
Liu, Y 1   VIAFID ORCID Logo  ; Tang, P Z 2 ; Gong, M Y 3 ; McCabe, R J 4 ; Wang, J 5 ; Tomé, C N 4 

1  State Key Lab of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai, China; Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM, USA 
2  State Key Lab of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai, China 
3  Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM, USA; Department of Mechanical & Materials Engineering, University of Nebraska-Lincoln, Lincoln, NE, USA 
4  Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, NM, USA 
5  Department of Mechanical & Materials Engineering, University of Nebraska-Lincoln, Lincoln, NE, USA 
Pages
1-7
Publication year
2019
Publication date
Jul 2019
Publisher
Nature Publishing Group
e-ISSN
20411723
Source type
Scholarly Journal
Language of publication
English
DOI
https://doi.org/10.1038/s41467-019-10573-7
ProQuest document ID
2264158149
Copyright
© 2019. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.