About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Ceramics and Ceramic-Based Composites for Nuclear Applications III
|
| Presentation Title |
Neutron Irradiation Effects on Thermal Conductivity and Dimensional Stability of TiC, TiB₂, and ZrB₂ Ultra-High-Temperature Ceramics |
| Author(s) |
Yan-Ru Lin, Takaaki Koyanagi, David Sprouster, Yutai Katoh |
| On-Site Speaker (Planned) |
Yan-Ru Lin |
| Abstract Scope |
Ultra-high-temperature ceramics (UHTCs), including TiC, TiB₂, and ZrB₂, show great potential for plasma-facing components due to their excellent high-temperature properties prior to irradiation; however, data on their neutron irradiation response remain limited and are essential for evaluating their viability. This study examines their thermal conductivity and dimensional stability following neutron irradiation at HFIR, ORNL, at temperatures of 200–1000°C and doses of 4–12 dpa. Thermal conductivity, measured at the irradiation temperature, improved with increasing temperature and ranged from 28–45 W/m·K, with a 32–40% reduction under the most extreme conditions. Significant bulk swelling was observed in the irradiated diborides but not in TiC, likely due to anisotropic cavity formation in the HCP structure. Lattice swelling peaked at 200°C and diminished at higher temperatures. At 600°C, both thermal conductivity degradation and lattice swelling saturated beyond 4 dpa. Transmission and scanning electron microscopy revealed the microstructural evolution responsible for these property changes. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Nuclear Materials, High-Temperature Materials, Characterization |