NSUF 25-5516: Comprehensive examination of the microstructure and physical properties of gamma-irradiated elastomers for advanced reactor seismic isolation devices
Several advanced reactor designs are considering seismic isolation and damping devices to both protect nuclear safety-critical assets from extreme earthquakes and to enable standardization. These devices are expected to be installed near the reactor vessel without shielding and therefore will be exposed to gamma radiation which may affect their mechanical behavior and seismic isolation performance. While changes in the global mechanical properties of the seismic protection devices are being investigated under an on-going project funded by the Nuclear Science User Facilities (NSUF), a fundamental understanding of radiation-induced degradation mechanisms at the material level as a function of absorbed gamma dose is lacking and is critical for a mechanistically-informed design approach of seismic isolation devices for advanced reactors. This NSUF Super Rapid Turnaround Experiment (RTE) aims to address this knowledge gap by performing a suite of multimodal post irradiation examination (PIE) characterization to ascertain the effects of gamma irradiation on the mechanical behavior and stability of elastomers/ rubbers used in seismic isolation devices. Laminated rubber sheets play a crucial role in seismic isolation devices that utilize elastomeric bearings. They provide horizontal flexibility and vertical rigidity, allowing the device to dissipate seismic energy without significant vertical deformation. Gamma irradiation can have induce various changers in the polymer properties of the rubber, including crosslinking, chain scission, and surface modification, that can have a detrimental effect on the performance of these elastomers in seismic isolation devices. To understand these degradation mechanisms, electron microscopy, X-ray diffraction, optical spectroscopy, differential scanning calorimetry, and mechanical testing will be used to assess the effects of irradiation on the microstructure, surface morphology, thermal stability, and mechanical properties of the elastomers. These experiments will provide new insight into radiation-induced degradation mechanisms in rubbers and help inform design limits and material selection for next-generation seismic isolation devices.
Additional Info
| Field | Value |
|---|---|
| Awarded Institution | Idaho National Laboratory |
| DOI | 10.46936/NSUF/60015716 |
| Embargo End Date | 2028-01-22 |
| Facility Tech Lead | Noé Morales |
| NSUF Call | FY 2025 Super RTE Call |
| PI | Amey Khanolkar |
| PIE Facilities | INL Research Center |
| Project Member | Dr. Amey Khanolkar, Applied Physicist - Idaho National Laboratory (https://orcid.org/0000-0003-0816-5507) |
| Project Member | Dr. Chandrakanth Bolisetti, Research Scientist - Idaho National Laboratory (https://orcid.org/0000-0001-8934-4835) |
| Project Member | Dr. Dean Peterman, Distinguished Staff Scientist - Idaho National Laboratory (https://orcid.org/0000-0003-4374-6948) |
| Project Type | RTE |