| About this Abstract |
| Meeting |
2020 TMS Annual Meeting & Exhibition
|
| Symposium
|
Deformation and Transitions at Grain Boundaries VII
|
| Presentation Title |
Structure and Kinetics of Three-dimensional Defects on the {10-12} Twin Boundary in Magnesium: Atomistic and Phase-field Simulations |
| Author(s) |
Douglas E. Spearot, Vincent Taupin, Khanh Dang, Laurent Capolungo |
| On-Site Speaker (Planned) |
Douglas E. Spearot |
| Abstract Scope |
The objective of this work is to characterize the structure and kinetics of three-dimensional defects created via the interaction between a dislocation shear loop and the {10-12} twin boundary in Mg. Molecular statics calculations show that the three-dimensional defects are bounded by nonequilibrium facets along the prismatic/basal (PB) and twist pyramidal/pyramidal (PP1) interfaces. The kinetics of the twin domain facets at finite temperature are analyzed by both molecular dynamics and a new anisotropic phase-field model. The latter allows the deconvolution of the competing role of interface energy, mobility and internal stress state. Molecular dynamics simulations show that inclined facets control the annihilation process; this behavior is captured in the phase-field model using mobility for the CTB interfaces that is significantly lower than that of crater inclined facets. Further, MD simulation results are best matched via the introduction of facet orientation dependent excess energies. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |