| About this Abstract |
| Meeting |
2021 TMS Annual Meeting & Exhibition
|
| Symposium
|
Composite Materials for Nuclear Applications
|
| Presentation Title |
Fabrication, Characterisation and Oxidation Resistance of an Innovative Composite Fuel: UN Microspheres Embedded in UO2 Matrix |
| Author(s) |
Diogo Ribeiro Costa, Marcus Hedberg, Simon Middleburgh, Janne Wallenius, Pär Olsson, Denise Adorno Lopes |
| On-Site Speaker (Planned) |
Diogo Ribeiro Costa |
| Abstract Scope |
UN-UO2 composite fuels are being considered as an accident tolerant fuel option for LWR. Mixtures of UN microspheres (10-50wt%) and UO2.13 powder were sintered by spark plasma sintering and characterised by XRD, DSC, and SEM-EDS/WDS/EBSD. The UN and UO2 interaction is driven by O diffusion into the UN phase and N diffusion in the opposite direction, forming a long-range solid solution (UO2-xNx) in the UO2 matrix. On cooling, the N solubility in UO2-xNx decreases and causes N redistribution and precipitation as α-U2N3 phase along and inside the UO2 grains. Additionally, TG/DSC investigations in air (30-700°C) show that the UO2 increases the oxidation onset temperature (OOT) from 260(3)°C (pure UN pellet) to 320(4)°C (10wt% UN-UO2 composite fuel). Composites with 30wt% and 50wt% UN present similar OOT (~285°C), which is similar to pure UO2 pellet (~300°C). Furthermore, the weight variations and the maximum reaction temperatures are reported and discussed. |
| Proceedings Inclusion? |
Planned: |