About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Steels in Extreme Conditions
|
| Presentation Title |
Microstructure of a Cu-Free High-Phosphorus High-Nickel RPV Steel Before and After Irradiation |
| Author(s) |
Anshul Kamboj, Mukesh Bachhav, Emmanuelle A. Marquis, Takuya Yamamoto, G. Robert Odette |
| On-Site Speaker (Planned) |
Anshul Kamboj |
| Abstract Scope |
The prolonged operation of light water reactors requires maintaining the structural integrity of their reactor pressure vessels (RPVs) during extended service periods. Neutron irradiation causes embrittlement in low alloy RPV steels, resulting in a shift in the brittle-to-ductile fracture transition temperature. Although extensive research has been conducted on embrittlement mechanisms, thorough examinations of both pre-irradiation and post-irradiation microstructures are still lacking. This study analyzes the microstructure of split-melt RPV steel before and after neutron irradiation. Before irradiation, Mo- and Fe-Mn-carbides, which influence fracture and strength, were found at both grain boundaries and in matrix. Additionally, a high density of dislocations decorated with small amounts of Mo, Mn, and C, and small segregation of Ni and Mn at the grain boundaries, were noted. Post-irradiation, Mn-Ni-Si-P precipitates were found in the matrix and at pre-existing dislocations, with increased solute segregation to grain boundaries and no changes to carbides. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Iron and Steel, Nuclear Materials, Characterization |