| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Microstructural, Mechanical, and Chemical Behavior of Solid Nuclear Fuel and Fuel-Cladding Interface II
|
| Presentation Title |
Investigating the Effect of Grain Growth Additive Incorporation on the Microstructure and Radiation Stability of UO2 Fuels |
| Author(s) |
Ritesh Mohun, Sarah Vallely, John Thomas Prabhakar , Simon Middleburgh |
| On-Site Speaker (Planned) |
Ritesh Mohun |
| Abstract Scope |
This work explores the effect of CrUO4 doping on the microstructure of UO2 as an innovative fuel design, as well as its radiation stability. Advanced TEM, Raman and XRD characterisations revealed that the precursor dissolves in the host lattice, leading to larger UO2 grains and denser microstructure. A CrUO4 pinning effect at grain boundaries was also observed which, at higher concentrations, changes the UO2 sintering mechanism.
Heavy-ion irradiation of both undoped and doped UO2 revealed that the dopant modifies the radiation defect kinetics in UO2 by enabling recombination pathways. The cation Frenkel pair formation enthalpy was calculated using DFT+U, revealing that uranium interstitials formed as part of displacement cascades in doped samples have a significant thermodynamic drive to displace any Cr substitutional defects. These modifications alter the defect mechanisms, enabling recombination pathways and allow for rapid recovery of the lattice. This mechanism is, however, not seen in undoped UO2. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Nuclear Materials, Characterization, Modeling and Simulation |