| About this Abstract |
| Meeting |
2023 TMS Annual Meeting & Exhibition
|
| Symposium
|
Advances in Multi-Principal Element Alloys II
|
| Presentation Title |
J-107: Thermal Super-jogs Control High-temperature Strength in Nb-Mo-Ta-W Alloys |
| Author(s) |
Sicong He, Xinran Zhou, Jaime Marian |
| On-Site Speaker (Planned) |
Sicong He |
| Abstract Scope |
Refractory multi-element alloys (RMEA) with bcc structure have been extensively studied over the last decade due to their potential for high-temperature applications. In this work, we propose a new strengthening mechanism based on thermal super-jogs in edge dislocation. The basis for the formation of super-jogs is in the vacancy formation energy distributions of RMEA. Vacancies at edge dislocation cores relax into super-jogs, hardening the alloy due to jog-pinning. At the same time, these super-jogs can displace diffusively along the glide direction, relieving some of the extra stress. We implement these mechanisms into a specially-designed hybrid kinetic Monte Carlo/Discrete Dislocation Dynamics approach (kMC/DD). The kMC module sets the timescale dictated by thermally-activated events, while the DD module relaxes the dislocation line configuration in between events. We find that the balance between super-jog pinning and super-jog diffusion confers an extra strength to edge dislocations that is in remarkable agreement with experimental measurements. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
High-Entropy Alloys, Modeling and Simulation, Mechanical Properties |