NSUF 19-1652: Local Deformation Mechanism of Neutron-Irradiated NF709 Austenitic Stainless Steel
This proposal is a follow-up to our previously awarded NSUF-RTE proposal 17-1014, which investigated the radiation-resulted microstructural evolution and hardening in four NF709 samples, showed the dose and temperature dependency of irradiation hardening in NF 709 alloys. The proposed study is to extend the understanding of deformation mechanisms in neutron irradiated austenitic alloys by conducting microstructure analysis of the indented samples. The objectives of this study are: (1) to compare the deformation microstructure of the irradiated samples at different grain orientations and deduce the governing microstructural deformation mechanisms according to the overall grain orientation distributions; (2) to elucidate the roles of radiation damage in deformation mechanisms by comparing with the result of previously-studied unirradiated control samples of NF709 and a model alloy; (3) to distinguish the roles of neutron irradiation on radiation hardening and nanoindentation creep properties following the strategy developed in the previous studies of the unirradiated controls. The scientific outcome includes mechanistic understanding of the roles of radiation damage in work hardening and dislocation propagations. The study will promote the fundamental understanding of dislocation-defect interactions, and provide guideline for the application of nanoindentation techniques to creep property studies for irradiated and unirradiated materials. The research will be conducted within six months after the proposal is awarded. The experiments will take up to three weeks and a high-quality journal paper is expected within three months after the experiments.
Additional Info
| Field | Value |
|---|---|
| Abstract | This proposal is a follow-up to our previously awarded NSUF-RTE proposal 17-1014, which investigated the radiation-resulted microstructural evolution and hardening in four NF709 samples, showed the dose and temperature dependency of irradiation hardening in NF 709 alloys. The proposed study is to extend the understanding of deformation mechanisms in neutron irradiated austenitic alloys by conducting microstructure analysis of the indented samples. The objectives of this study are: (1) to compare the deformation microstructure of the irradiated samples at different grain orientations and deduce the governing microstructural deformation mechanisms according to the overall grain orientation distributions; (2) to elucidate the roles of radiation damage in deformation mechanisms by comparing with the result of previously-studied unirradiated control samples of NF709 and a model alloy; (3) to distinguish the roles of neutron irradiation on radiation hardening and nanoindentation creep properties following the strategy developed in the previous studies of the unirradiated controls. The scientific outcome includes mechanistic understanding of the roles of radiation damage in work hardening and dislocation propagations. The study will promote the fundamental understanding of dislocation-defect interactions, and provide guideline for the application of nanoindentation techniques to creep property studies for irradiated and unirradiated materials. The research will be conducted within six months after the proposal is awarded. The experiments will take up to three weeks and a high-quality journal paper is expected within three months after the experiments. |
| Award Announced Date | 2019-02-08T00:00:00 |
| Awarded Institution | University of California-Berkeley |
| Facility | Nuclear Materials Laboratory |
| Facility Tech Lead | Peter Hosemann, Yaqiao Wu |
| Irradiation Facility | None |
| PI | Tianyi Chen |
| PI Email | [email protected] |
| Project Type | RTE |
| RTE Number | 1652 |