Assessment of irradiation embrittlement effect on fatigue life of a pressurized-water reactor pressure vessel using the fracture toughness master curve approach
Journal Article
·
· Nuclear Engineering and Design
- Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, NSW (Australia); Univ. of New South Wales, Kensington, NSW (Australia)
- Idaho National Laboratory (INL), Idaho Falls, ID (United States)
The reactor pressure vessel (RPV) is a critical structural component in pressurized-water reactors, and it is designed to withstand extreme conditions, such as high pressures, elevated temperatures, and prolonged radiation exposure. Ensuring RPV integrity is essential for the safe and reliable long-term operation of nuclear power plants, especially as aging mechanisms such as fatigue and irradiation embrittlement pose increased risks. Fatigue, caused by cyclic thermal and mechanical loading, can lead to crack initiation in localized high-stress regions. Simultaneously, neutron irradiation, particularly in the beltline region, progressively reduces fracture toughness, increasing susceptibility to brittle fracture. These combined effects of fatigue and irradiation embrittlement potentially impact the RPV structural integrity, necessitating fitness-for-service assessments. This study applies the fracture toughness master curve approach to evaluate the impact of irradiation embrittlement on RPV fatigue life. A coupled thermo-mechanical stress analysis identifies critical stress locations under normal service transients, pinpointing regions most vulnerable to fatigue crack initiation and growth. Stress intensity factors for postulated flaws at these locations are calculated, enabling an assessment of fatigue life under irradiated and unirradiated conditions. The results indicate that neutron irradiation embrittlement accelerates the conditions in which a critical crack can form and lead to failure, particularly at lower temperatures. The failure occurs where reduced fracture toughness limits the material’s resistance to crack growth. Axial cracks at nozzle corners are the most life limiting without irradiation, while circumferential cracks demonstrate longer fatigue lives. The findings highlight the importance of incorporating irradiation effects into fatigue life predictions to ensure the long-term structural integrity of RPVs.
- Research Organization:
- Idaho National Laboratory (INL), Idaho Falls, ID (United States)
- Sponsoring Organization:
- USDOE Office of Nuclear Energy (NE); USDOE Office of Science (SC)
- Grant/Contract Number:
- AC07-05ID14517
- OSTI ID:
- 3013749
- Report Number(s):
- INL/JOU--25-83090
- Journal Information:
- Nuclear Engineering and Design, Journal Name: Nuclear Engineering and Design Vol. 443; ISSN 0029-5493
- Publisher:
- ElsevierCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
Resolution of the reactor vessel materials toughness safety issue; Task Action Plan A-11; Appendices C-K
Resolution of the reactor vessel materials toughness safety issue; Task Action Plan A-11; main report and Appendixes A and B
Resolution of the Task A-11 reactor-vessel materials-toughness safety issue. Appendices C-K. [PWR; BWR]
Technical Report
·
Tue Sep 01 00:00:00 EDT 1981
·
OSTI ID:5477204
Resolution of the reactor vessel materials toughness safety issue; Task Action Plan A-11; main report and Appendixes A and B
Technical Report
·
Tue Sep 01 00:00:00 EDT 1981
·
OSTI ID:5486076
Resolution of the Task A-11 reactor-vessel materials-toughness safety issue. Appendices C-K. [PWR; BWR]
Technical Report
·
Fri Oct 01 00:00:00 EDT 1982
·
OSTI ID:6675549