About this Abstract |
Meeting |
2025 TMS Annual Meeting & Exhibition
|
Symposium
|
Computational Thermodynamics and Kinetics
|
Presentation Title |
Stress-driven void emission from edge dislocation jogs in FCC metals |
Author(s) |
Yifan Wang, Wu-Rong Jian, Wei Cai |
On-Site Speaker (Planned) |
Yifan Wang |
Abstract Scope |
Dislocation jogs are typically formed while cutting through forest dislocations or obstacles, which plays an important role in dislocation multiplication and thus strain hardening. In FCC metals and alloys, jogs on screw dislocations are structurally pinned and can only move by emitting vacancies. However, how edge dislocation jogs impose frictions remains unclear. In this work, we employ molecular dynamics simulations to explore the dragging effect of a unit jog pair on an edge dislocation in single-crystal nickel. We find that the dragging friction comes from the deformation of a constricted jog in the jog pair at low applied stresses. Notably, with high applied stress, vacancies start to emit from the extremely deformed constricted jog even at room temperature. Further analysis reveals that the void emission is a stress-driven thermally activated process, where the jogs climb along the dislocation line at a temperature way below the creep condition. |
Proceedings Inclusion? |
Planned: |
Keywords |
Modeling and Simulation, Mechanical Properties, Computational Materials Science & Engineering |