Abstract
Post-irradiation evaluation was performed on a 316 stainless steel baffle former bolt harvested after 40 years of service in a pressurized water reactor. Microstructure analysis revealed the presence of defect-free dislocation channels and strain-induced twins, indicative of loading at a stress level close to yield stress at least once while in service. Primary radiation-induced Ni/Si precipitates were likely destroyed during channel and twin formation, and secondary, significantly coarser Ni/Si precipitates formed inside the newly formed dislocation channels and along ∑3 boundaries during the continued irradiation. Complex chemistry inside the strain-induced features may overlap with dislocation pileups and impact localized corrosion and material long-term performance.
Original language | English |
---|---|
Article number | 116371 |
Journal | Scripta Materialia |
Volume | 255 |
DOIs | |
State | Published - Jan 15 2025 |
Funding
The research was supported by the US Department of Energy, Office of Nuclear Energy, Light Water Reactor Sustainability Program Materials Research Pathway. This manuscript has been authored by UT-Battelle, LLC, under contract DE-AC05\u201300OR22725 with the US Department of Energy (DOE). The US government retains and the publisher, by accepting the article for publication, acknowledges that the US government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for US government purposes. DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan). The authors would like to thank Patricia Tedder and Travis Dixon at the Low Activation Materials Development and Analysis (LAMDA) Laboratory at ORNL, where SEM and TEM/STEM evaluation was conducted. Microscopy in LAMDA is a cost recovery center available for users through the US-DOE Nuclear Science User Facilities. The Thermo Fisher Talos 200X STEM in LAMDA was purchased and funded through the US-DOE Office of Nuclear Energy Advanced Fuel Campaign and Nuclear Science User Facilities. The authors would like to thank the late Mike Burke who was involved in the bolt harvesting and characterization planning and led the sample preparation, machining, and shipping when he was working at Westinghouse Electric Company. The research was supported by the US Department of Energy, Office of Nuclear Energy, Light Water Reactor Sustainability Program Materials Research Pathway . This manuscript has been authored by UT-Battelle, LLC, under contract DE-AC05-00OR22725 with the US Department of Energy (DOE) . The US government retains and the publisher, by accepting the article for publication, acknowledges that the US government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for US government purposes. DOE will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan ( http://energy.gov/downloads/doe-public-access-plan ). The authors would like to thank Patricia Tedder and Travis Dixon at the Low Activation Materials Development and Analysis (LAMDA) Laboratory at ORNL , where SEM and TEM/STEM evaluation was conducted. Microscopy in LAMDA is a cost recovery center available for users through the US-DOE Nuclear Science User Facilities. The Thermo Fisher Talos 200X STEM in LAMDA was purchased and funded through the US-DOE Office of Nuclear Energy Advanced Fuel Campaign and Nuclear Science User Facilities. The authors would like to thank the late Mike Burke who was involved in the bolt harvesting and characterization planning and led the sample preparation, machining, and shipping when he was working at Westinghouse Electric Company.
Keywords
- Baffle former bolts
- In-service radiation
- Radiation-induced segregation (RIS)
- Stainless steel
- Strain localization