| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Chemistry and Physics of Interfaces
|
| Presentation Title |
An Atomistic Study of Twin Boundary Structure and Migration in Tetragonal Beta-Sn |
| Author(s) |
Ian Chesser, Khanh Dang, Mashroor Nitol , Esther Hessong, Himanshu Joshi, Nikhil Admal, Abigail Hunter, Saryu Fensin, Daniel Blaschke |
| On-Site Speaker (Planned) |
Ian Chesser |
| Abstract Scope |
We conduct the first atomistic study of twin boundary migration in a tetragonal material, beta-Sn. We analyze the structure, energy and shear coupled migration of the two most commonly observed twin boundaries in beta-Sn, the (301) and (-101) twins, via a combination of ab-initio calculations and molecular dynamics simulations employing classical and machine-learning based potentials. The (301) coherent twin is found to migrate with a small twinning shear, consistent with theoretical predictions. A two layer disconnection mechanism is observed consistent with the topological model. Athermal flow stress behavior is attributed to easy disconnection nucleation and migration. In analogy to Prismatic-Basal (PB) interfaces in HCP metals, we discover a low energy asymmetric Prismatic-A-plane (PA) interface important to twin growth in beta-Sn. Conjugate twin facets and PA facets have additional disclination character which impacts boundary structure and dynamics compared to fully coherent boundaries. We connect our findings to existing experimental literature. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Thin Films and Interfaces, Mechanical Properties, Modeling and Simulation |