| About this Abstract |
| Meeting |
Materials in Nuclear Energy Systems (MiNES) 2021
|
| Symposium
|
Materials in Nuclear Energy Systems (MiNES) 2021
|
| Presentation Title |
Microstructural Analysis of Oxidized Tristructural Isotropic Particles (TRISO) in Mixed Gas Atmospheres |
| Author(s) |
Katherine Montoya, Brian A. Brigham, Tyler Gerczak, Elizabeth S Sooby |
| On-Site Speaker (Planned) |
Katherine Montoya |
| Abstract Scope |
Certain, proposed off-normal scenarios lead to the exposure of HTGR fuel elements to steam. Subsequently, graphite matrix degradation and OPyC evolution will produce volatile gaseous oxidation products and potentially expose the TRISO particle’s SiC layer to a mixed gas atmosphere. The SiC layer acts as the structural component and primary fission product barrier; oxidation induced damage to the SiC can lead to particle failure. This study investigates the impact of steam ingress to the SiC layer by characterizing microstructure evolution of the oxidized surface. Surrogate, SiC exposed, TRISO particle oxidation testing atmospheres in the thermogravimetric analyzer included low partial pressures of steam (<0.2 atm H2O) and carbon monoxide (<1000 ppm) at high temperatures (1300ºC < T <1600 ºC). Microstructural analysis of the oxidized SiO2-SiC interface was performed utilizing focused ion beam milling, scanning electron microscopy and limited transmission electron microscopy in addition to surface chemistry analysis via x-ray photoelectron spectroscopy. |
| Proceedings Inclusion? |
Undecided |