NSUF 16-790: Microstructural evolution of dual-phase cast stainless steels under irradiation
The embrittlement of cast austenitic stainless steels and stainless steel welds is a critical issue for aging nuclear power plants. Irradiation-induced defect and precipitate microstructures are responsible for the deteriorated mechanical performance after long-term service exposure to reactor environments. Previous studies have showed that irradiation dose rates and pre-existing precipitates induced by thermal aging can affect the microstructural evolution. The proposed study is to investigate the effects of dose rate and pre-existing neutron-irradiated microstructure on the phase stability and defect evolution of duplex microstructures under irradiation. The material to be investigated is a CF-8 alloy with approximately 20% ferrite. The focus of the study is the kinetics of defect evolution with and without the pre-neutron-irradiated microstructure, and the evolution of G-phase precipitation and spinodal decomposition of delta ferrite. The results will be used along with mechanical tests to improve our understanding on the embrittlement mechanism of CASS and SS welds under service conditions.
Additional Info
| Field | Value |
|---|---|
| Abstract | The embrittlement of cast austenitic stainless steels and stainless steel welds is a critical issue for aging nuclear power plants. Irradiation-induced defect and precipitate microstructures are responsible for the deteriorated mechanical performance after long-term service exposure to reactor environments. Previous studies have showed that irradiation dose rates and pre-existing precipitates induced by thermal aging can affect the microstructural evolution. The proposed study is to investigate the effects of dose rate and pre-existing neutron-irradiated microstructure on the phase stability and defect evolution of duplex microstructures under irradiation. The material to be investigated is a CF-8 alloy with approximately 20% ferrite. The focus of the study is the kinetics of defect evolution with and without the pre-neutron-irradiated microstructure, and the evolution of G-phase precipitation and spinodal decomposition of delta ferrite. The results will be used along with mechanical tests to improve our understanding on the embrittlement mechanism of CASS and SS welds under service conditions. |
| Award Announced Date | 2016-12-16T07:45:28.487 |
| Awarded Institution | Center for Advanced Energy Studies |
| Facility | Microscopy and Characterization Suite |
| Facility Tech Lead | Alina Zackrone, Wei-Ying Chen, Yaqiao Wu |
| Irradiation Facility | None |
| PI | Yiren Chen |
| PI Email | [email protected] |
| Project Type | RTE |
| RTE Number | 790 |