NSUF 20-4110: Determination of the evolution of residual stress in nuclear graphite with irradiation
The objective of this RTE is to determine irradiation-induced changes in residual stress in complex machined nuclear graphite parts. Residual stress in nuclear graphite is a result of the graphitization process and the machining. The stress both builds and relaxes due to irradiation. There is a need for accurate predictions of the strength of graphite components, its evolution with irradiation, and as such for validation of core structural codes. Currently, there are several distinctly different stress analysis codes for graphite components. No consensus, unified stress analysis code for graphite components has been verified and validated, in part because of difficulties in direct high-resolution measurements of the residual stress of complex structural components. The significance of this proposal is in capability demonstration for such measurements. We will measure the residual stress in machined graphite parts before and after irradiation by neutron diffraction, a golden standard and the most direct way of residual strain measurements. Such capability, if successfully demonstrated, will be later used to validate the codes and establish benchmarking procedures. The project will take about nine months, including preparing and shipping the samples to SMARTS neutron diffractometer at Los Alamos Neutron Science Center, measurements at SMARTS, and data analysis and interpretation. The outcome will be the residual strain maps of machined graphite, and their evolution with irradiation.
Additional Info
| Field | Value |
|---|---|
| Abstract | The objective of this RTE is to determine irradiation-induced changes in residual stress in complex machined nuclear graphite parts. Residual stress in nuclear graphite is a result of the graphitization process and the machining. The stress both builds and relaxes due to irradiation. There is a need for accurate predictions of the strength of graphite components, its evolution with irradiation, and as such for validation of core structural codes. Currently, there are several distinctly different stress analysis codes for graphite components. No consensus, unified stress analysis code for graphite components has been verified and validated, in part because of difficulties in direct high-resolution measurements of the residual stress of complex structural components. The significance of this proposal is in capability demonstration for such measurements. We will measure the residual stress in machined graphite parts before and after irradiation by neutron diffraction, a golden standard and the most direct way of residual strain measurements. Such capability, if successfully demonstrated, will be later used to validate the codes and establish benchmarking procedures. The project will take about nine months, including preparing and shipping the samples to SMARTS neutron diffractometer at Los Alamos Neutron Science Center, measurements at SMARTS, and data analysis and interpretation. The outcome will be the residual strain maps of machined graphite, and their evolution with irradiation. |
| Award Announced Date | 2020-07-14T14:06:12.503 |
| Awarded Institution | Idaho National Laboratory |
| Facility | Advanced Test Reactor |
| Facility Tech Lead | Alina Zackrone, Gordon Kohse, Tarik Saleh |
| Irradiation Facility | None |
| PI | Boris Khaykovich |
| PI Email | [email protected] |
| Project Type | RTE |
| RTE Number | 4110 |