| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 296035 | Nuclear Engineering and Design | 2015 | 8 Pages |
•Fabricated UO2–diamond composite fuel pellets using spark plasma sintering (SPS).•Increased thermal conductivity by up to 41.6% compared to standard pure UO2 fuel.•Investigated the effect of diamond particle size on properties of composites.
In an effort to increase the thermal conductivity of UO2 fuel pellets, high density UO2–5 vol% diamond composite pellets were fabricated using the spark plasma sintering (SPS) technique. Diamond particles with nano-size (0.25 μm) and several micro-sizes (3 μm, 12 μm and 25 μm) were mixed with UO2 powder and sintered using SPS at 1300–1600 °C with a hold time of 5 min. The resultant density, chemical reaction, microstructure, thermal conductivity and Young's modulus of the sintered pellets were investigated. The pellets with 3 μm diamond particles had a uniform distribution of particles as well as better thermal and mechanical properties compared to others. An increase in thermal conductivity of up to 41.6%, 38.3% and 34.2% at 100 °C, 500 °C and 900 °C, respectively, was measured in the UO2–diamond composite pellets compared to the pure UO2 fuel pellets.
