| About this Abstract |
| Meeting |
2020 TMS Annual Meeting & Exhibition
|
| Symposium
|
2020 Technical Division Student Poster Contest
|
| Presentation Title |
SPG-71: Kinetic Evolution of Metastable Grain Boundaries under
Non-equilibrium Processing |
| Author(s) |
Zhitong Bai, Glenn Balbus, Daniel Gianola, Yue Fan |
| On-Site Speaker (Planned) |
Zhitong Bai |
| Abstract Scope |
The energetic evolution of a group of Cu <100> symmetric tilt grain boundaries (GBs) subjected to fast thermal cycling are investigated via atomistic modeling, wherein a universal hysteretic response is observed. Utilizing an efficient data-mining algorithm, the GBs’ energetic evolution rates are mapped out over the metastability-temperature space, wherein two distinct regimes—an ageing regime and a rejuvenating regime—are retrieved with high fidelity. We further demonstrate that the ageing/rejuvenating crossover can be attributed to the energy imbalance along with the sequential hopping in the system’s underlying potential energy landscape. Such a kinetic analysis enables a self-consistent equation describing the system’s energetic evolution, and thus the resultant mechanical behavior. The developed model reconciles experimental measurements of non-equilibrium grain boundaries in nanocrystalline metals without invoking free fitting parameters. Furthermore, these results provide a new perspective on kinetic pathways for achieving various interfacial states, and thereby facilitates previously inaccessible property regimes. |
| Proceedings Inclusion? |
Undecided |