Symmetric or asymmetric glide resistance to twinning disconnection?

Authors

Mingyu Gong, Shanghai Jiao Tong University
Houyu Ma, Shanghai Jiao Tong University
Kunming Yang, Shanghai Jiao Tong University
Yue Liu, Shanghai Jiao Tong University
Jian-Feng Nie, Monash University
Jian Wang, University of Nebraska-LincolnFollow

Date of this Version

2022

Citation

npj Computational Materials (2022) 8:168 ; https://doi.org/10.1038/s41524-022-00855-y

Comments

Open access

Abstract

Successive gliding of twinning disconnections (TDs) creates three-dimensional twins in parent crystal and accommodates shear deformation. It is generally recognized that TD is subject to the same Peierls stress as it glides forward or backward because of its dislocation character and the twofold rotation symmetry of the twin plane. Based on atomistic simulations, we demonstrate that the glide of TDs may be subject to a symmetric or asymmetric resistance corresponding to step character, symmetric resistance for A/A type steps but asymmetric resistance for A/B type steps, where A and B represent crystallographic planes in twin and matrix. Furthermore, we experimentally demonstrate that the asymmetric resistance results in asymmetric propagation and growth of twins in Mg alloys.