About this Abstract |
Meeting |
2024 TMS Annual Meeting & Exhibition
|
Symposium
|
Chemistry and Physics of Interfaces
|
Presentation Title |
Radiation Induced Steady State Grain Boundary Structures and Their Dynamics |
Author(s) |
Ian Chesser, Sarah Paguaga, Peter Derlet, Abigail Hunter, Blas Uberuaga, Saryu Fensin |
On-Site Speaker (Planned) |
Ian Chesser |
Abstract Scope |
The complex radiation-induced defect evolution of alloys near grain boundaries (GBs) is still poorly understood. We employ atomistic simulations to study the high radiation dose limit of grain boundary (GB) structures for many types of Ni GBs. We find that, upon continuously loading a GB with Frenkel pairs in the athermal limit, a steady state disordered GB structure is reached. Collective dynamics are commonly observed including string-like structural excitations and GB migration. Steady state GB structures can be described as a superposition of the pristine GB structure with absorbed interstitials, a non-equilibrium vacancy atmosphere and accumulated line defects such as disconnections and dislocations. Steady state GB structures vary with macroscopic GB crystallography, but are found to depend only weakly on initial metastable GB structure. The mechanical responses of pristine and irradiated GB structures are compared and the implications of different behavior are discussed. |
Proceedings Inclusion? |
Planned: |
Keywords |
Computational Materials Science & Engineering, Modeling and Simulation, Thin Films and Interfaces |