About this Abstract |
| Meeting |
Materials in Nuclear Energy Systems (MiNES) 2025
|
| Symposium
|
Materials in Nuclear Energy Systems (MiNES) 2025
|
| Presentation Title |
The Mechanisms Behind Irradiation-Induced Grain Subdivision |
| Author(s) |
Sadie A. Wicks, Brandon Bohanon, Michenna Allen, Benjamin Mejia Diaz, Zhihan Hu, Alec Pfundheller, Lin Shao, Michael Tonks, Simon Phillpot, Assel Aitkaliyeva |
| On-Site Speaker (Planned) |
Sadie A. Wicks |
| Abstract Scope |
Irradiation-induced grain subdivision (IIGS), commonly referred to as high burnup structure (HBS) in
nuclear fuels, is characterized by extensive changes in the material microstructure. The
fundamental mechanisms driving IIGS have not been confirmed but have been presumed to be
polygonization to form low-angle grain boundaries (LAGBs) and/or nucleation to form high-angle
grain boundaries (HAGBs).In this study, we investigate IIGS on the basis that it is similar to
continuous dynamic recrystallization (CDRX) since CDRX’s primary mechanisms consist of LAGBs
evolving into HAGBs as dislocations are absorbed.
We use high-purity aluminum for its high stacking fault energy and its proven ability to undergo IIGS
and CDRX. Al samples were irradiated ex-situ with He+ ions at 50 keV at fluences 1x1014 - 1x1017 cm
2to assess the change in LAGBs to HAGBs. TEM was used to determine how radiation damage
resulted in dislocation networks and how LAGBs evolved into HAGBs. In situ irradiations equipped
with TEM and precession electron diAraction (PED) were carried out at fluences where grain
subdivision began and where grain subdivision was the most prominent to observe the evolution of
grain subdivision and grain boundary evolution live. |
| Proceedings Inclusion? |
Undecided |