NSUF 15-559: Investigating alpha prime precipitation in a neutron irradiated NFA (Nanostructured Ferritic Alloy)
The objectives of this project are: 1) Examine microstructural changes in the neutron irradiated 14CrYWT (sample YC-11 14CrYWT-UCSB C 1150C) at an atomic scale using atom probe tomography. 2) Determine the size, number density, and composition of alpha prime precipitates within the neutron irradiated 14CrYWT. 3) Ascertain whether the presence of ultrafine dispersoids in NFAs (Nanostructured Ferritic Alloys) act as preferential nucleation sites for alpha prime precipitates. 4) Identify the kinetics of precipitation formation by comparing the alpha prime precipitate population in the neutron irradiated alloy with isothermally aged 14CrYWT at 475°C for a duration of 10 months (this duration matches the duration of the neutron irradiation experiment); and a 14CrYWT ion irradiated to the same dose and at the same temperature as the neutron irradiated alloy (it should be noted that the analysis of the isothermally aged and ion irradiated samples are not part of this proposal) To fulfil these objectives access to the Local Electrode Atom Probe (LEAP) at CAES is requested to analyse the evolved microstructure within the neutron irradiated 14CrYWT sample. This equipment is capable of providing the required compositional and morphological data on the precipitates. The data accrued will also be used to determine the precipitation kinetics and the role of alloying species and impurities. The experiments described in this proposal and the parallel modelling efforts have not been conducted previously and will contribute to the understanding of the behaviour of Fe-14Cr based alloys in tokamak-like conditions.
Additional Info
| Field | Value |
|---|---|
| Abstract | The objectives of this project are: 1) Examine microstructural changes in the neutron irradiated 14CrYWT (sample YC-11 14CrYWT-UCSB C 1150C) at an atomic scale using atom probe tomography. 2) Determine the size, number density, and composition of alpha prime precipitates within the neutron irradiated 14CrYWT. 3) Ascertain whether the presence of ultrafine dispersoids in NFAs (Nanostructured Ferritic Alloys) act as preferential nucleation sites for alpha prime precipitates. 4) Identify the kinetics of precipitation formation by comparing the alpha prime precipitate population in the neutron irradiated alloy with isothermally aged 14CrYWT at 475°C for a duration of 10 months (this duration matches the duration of the neutron irradiation experiment); and a 14CrYWT ion irradiated to the same dose and at the same temperature as the neutron irradiated alloy (it should be noted that the analysis of the isothermally aged and ion irradiated samples are not part of this proposal) To fulfil these objectives access to the Local Electrode Atom Probe (LEAP) at CAES is requested to analyse the evolved microstructure within the neutron irradiated 14CrYWT sample. This equipment is capable of providing the required compositional and morphological data on the precipitates. The data accrued will also be used to determine the precipitation kinetics and the role of alloying species and impurities. The experiments described in this proposal and the parallel modelling efforts have not been conducted previously and will contribute to the understanding of the behaviour of Fe-14Cr based alloys in tokamak-like conditions. |
| Award Announced Date | 2015-04-22T00:00:00 |
| Awarded Institution | None |
| Facility | None |
| Facility Tech Lead | Yaqiao Wu |
| Irradiation Facility | None |
| PI | Kris Bhojwani |
| PI Email | [email protected] |
| Project Type | RTE |
| RTE Number | 559 |