| About this Abstract |
| Meeting |
2022 TMS Annual Meeting & Exhibition
|
| Symposium
|
Grain Boundaries and Interfaces: Metastability, Disorder, and Non-Equilibrium Behavior
|
| Presentation Title |
Nudged Elastic Band-based Modeling of Stress-dependent Twin Boundary Migration in Magnesium |
| Author(s) |
Kehang Yu, Xin Wang, Subhash Mahajan, Timothy Rupert, Irene Beyerlein, Penghui Cao, Julie Schoenung, Enrique Lavernia |
| On-Site Speaker (Planned) |
Kehang Yu |
| Abstract Scope |
Twin thickening occurs by the migration of the twin boundary upon deformation and serves as a mechanism for accommodating plastic strain. Twin boundary migration is strongly affected by the local stress state, which is hard to determine experimentally. We investigate {10-12} coherent twin boundary (CTB) migration in magnesium under various stress fields using the nudged elastic band method to calculate its minimum energy path. Our results reveal an appreciable influence of a non-glide stress on CTB migration in addition to that of the resolved shear stress. Specifically, a compressive normal stress makes it significantly easier for CTB migration to occur, even under subcritical shear stresses. We formulate a model to describe the evolution of the energy barrier as a function of stress. We also find that the configuration of twinning disconnections depends on the applied stress field and exhibits a compression-tension asymmetry. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Computational Materials Science & Engineering, Magnesium, |