Abstract
Silicon carbide (SiC) fiber–reinforced SiC matrix (SiC/SiC) composites are being actively investigated for use in accident-tolerant core structures of light water reactors (LWRs). Owing to the limited number of irradiation studies previously conducted at LWR-coolant temperature, this study examined SiC/SiC composites following neutron irradiation at 230–340 °C to 2.0 and 11.8 dpa in the High Flux Isotope Reactor. The investigated materials were chemical vapor infiltrated (CVI) SiC/SiC composites with three different reinforcement fibers. The fiber materials were monolayer pyrolytic carbon (PyC) -coated Hi-Nicalon™ Type-S (HNS), Tyranno™ SA3 (SA3), and SCS-Ultra™ (SCS) SiC fibers. The irradiation resistance of these composites was investigated based on flexural behavior, dynamic Young's modulus, swelling, and microstructures. There was no notable mechanical properties degradation of the irradiated HNS and SA3 SiC/SiC composites except for reduction of the Young's moduli by up to 18%. The microstructural stability of these composites supported the absence of degradation. In addition, no progressive swelling from 2.0 to 11.8 dpa was confirmed for these composites. On the other hand, the SCS composite showed significant mechanical degradation associated with cracking within the fiber. This study determined that SiC/SiC composites with HNS or SA3 SiC/SiC fibers, a PyC interphase, and a CVI SiC matrix retain their properties beyond the lifetime dose for LWR fuel cladding at the relevant temperature.
| Original language | English |
|---|---|
| Pages (from-to) | 46-54 |
| Number of pages | 9 |
| Journal | Journal of Nuclear Materials |
| Volume | 494 |
| DOIs | |
| State | Published - Oct 2017 |
Funding
This research was supported by the United States Department of Energy (DOE) Office of Nuclear Energy for the Advanced Fuels Campaign of the Nuclear Technology R&D program under contact DE-AC05-00OR22725 with Oak Ridge National Laboratory (ORNL) managed by UT Battelle, LLC. A portion of this research used resources at the High Flux Isotope Reactor, a DOE Office of Science User Facility operated by ORNL. This work also used resources at the High Temperature Materials Laboratory at ORNL. The authors would like to thank Nesrin Cetiner at ORNL for design of the irradiation capsules and simulation of the irradiation temperature. The authors wish to thank Anne Campbell and Caen Ang at ORNL for valuable comments of this manuscript.
| Funders | Funder number |
|---|---|
| DOE Office of Science | |
| United States Department of Energy | |
| U.S. Department of Energy | DE-AC05-00OR22725 |
| Battelle | |
| Oak Ridge National Laboratory |