About this Abstract |
Meeting |
2024 TMS Annual Meeting & Exhibition
|
Symposium
|
Defects and Interfaces: Modeling and Experiments
|
Presentation Title |
Migration Velocities of Intergranular He Gas Bubbles Under Thermal Gradients in Fe by Phase-field Modeling |
Author(s) |
Yixi Shen, Peng Wen, An Ta, Simon Phillpot, Douglas Spearot |
On-Site Speaker (Planned) |
Yixi Shen |
Abstract Scope |
We compute the migration velocity of intergranular He bubbles in Fe under thermal gradients using phase-field (PF) modeling. Grain boundaries (GBs) with energies in the range of 0.88-1.6 J/m^2 are considered. The influences of the PF parameterization strategy, thermal conductivity in grain boundaries, and GB diffusion coefficients on intergranular He bubble geometry are addressed. Under the application of a thermal gradient, we find that intergranular He bubbles migrate slower than He bubbles in an Fe matrix. We show that this is a result of the smaller temperature gradient at the bubble/GB junction when the bubble is at the GB, than when the bubble is in the matrix. We find the shape of the bubble influences intergranular bubble migration velocity. An analytical model for bubble migration velocity that considers the shape of an intergranular bubble is proposed and shown to capture the computed PF data for He bubbles. |
Proceedings Inclusion? |
Planned: |
Keywords |
Modeling and Simulation, |