NSUF 19-1793: Elevated Temperature In-situ Scanning Electron Microscopy Microcantilever Testing of U3Si2
The PI has access to several different U3Si2 samples at the Fuels Research Laboratory at Los Alamos National Laboratory and the team knowledge and facilities to grow the grains large enough to fit several microcantilevers specimens in an individual grain. In addition, the PI also has access to U3Si2 single crystals for these experiments. The ability to fit multiple microcantilever specimens in a single grain or on a single crystal would allow the direct comparison of deformation behavior of the microcantilever tests at each temperature. In addition, having all of the measurements in a single grain or single crystal would remove the elastic anisotropy and reduce the porosity scatter and allow one to obtain the intrinsic property scatter which is an important input parameter for modeling efforts. In addition, while removing the effects of the anisotropy in the testing by having all of the microcantilevers in a particular orientation a single crystal could allow for systemically evaluating the anisotropy of U3Si2. The microcantilever geometry was chosen because it would provide valuable data like the elastic modulus and fracture stress that is need in modeling the pellet clad mechanical interaction. In addition the microcantilever testing will be used to produce stress-strain curves, measure the yield stress if ductile behavior is observed, and evaluate the deformation of U3Si2 in the temperature range from RT-700 ºC to elucidate the change in the properties over this temperature range.
The SEM/FIB at Los Alamos National Laboratory will be used to manufacture the microcantilever specimens. Pre-milling electron backscatter diffraction will be performed on the samples to locate individual grains large enough to manufacture multiple microcantilever specimens in. If a single crystal is used the electron backscatter diffraction will be used to identify the orientation the microcantilevers are milled in. The sample with the manufactured microcantilevers will then be shipped to UC Berkeley were the PI-88 will be used to perform the in-situ SEM room and elevated temperature microcantilever testing. The SEM/FIB will then be used post testing to evaluate the microstructure of the deformed regions of the U3Si2. This will allow the ability to evaluate the deformation mechanisms in the U3Si2.
This proposal seeks to measure the mechanical properties of U3Si2 in the temperature range (RT-700 ºC) using small scale mechanical testing (microcantilever) in order to increase the mechanical data available for modeling efforts. These results would add to the knowledge of the mechanical behavior of U3Si2 in a reactor core which would improve the predictive modeling in the MARMOT-BISON-MOOSE framework and increase the ability to evaluate this fuel as potential accident tolerant fuel for the nation’s current nuclear infrastructure. The work aims to measure the elastic modulus, fracture stress and evaluate the deformation of U3Si2 using microcantilever testing in the temperature range of RT-700 ºC.
Additional Info
| Field | Value |
|---|---|
| Abstract | The PI has access to several different U3Si2 samples at the Fuels Research Laboratory at Los Alamos National Laboratory and the team knowledge and facilities to grow the grains large enough to fit several microcantilevers specimens in an individual grain. In addition, the PI also has access to U3Si2 single crystals for these experiments. The ability to fit multiple microcantilever specimens in a single grain or on a single crystal would allow the direct comparison of deformation behavior of the microcantilever tests at each temperature. In addition, having all of the measurements in a single grain or single crystal would remove the elastic anisotropy and reduce the porosity scatter and allow one to obtain the intrinsic property scatter which is an important input parameter for modeling efforts. In addition, while removing the effects of the anisotropy in the testing by having all of the microcantilevers in a particular orientation a single crystal could allow for systemically evaluating the anisotropy of U3Si2. The microcantilever geometry was chosen because it would provide valuable data like the elastic modulus and fracture stress that is need in modeling the pellet clad mechanical interaction. In addition the microcantilever testing will be used to produce stress-strain curves, measure the yield stress if ductile behavior is observed, and evaluate the deformation of U3Si2 in the temperature range from RT-700 ºC to elucidate the change in the properties over this temperature range. The SEM/FIB at Los Alamos National Laboratory will be used to manufacture the microcantilever specimens. Pre-milling electron backscatter diffraction will be performed on the samples to locate individual grains large enough to manufacture multiple microcantilever specimens in. If a single crystal is used the electron backscatter diffraction will be used to identify the orientation the microcantilevers are milled in. The sample with the manufactured microcantilevers will then be shipped to UC Berkeley were the PI-88 will be used to perform the in-situ SEM room and elevated temperature microcantilever testing. The SEM/FIB will then be used post testing to evaluate the microstructure of the deformed regions of the U3Si2. This will allow the ability to evaluate the deformation mechanisms in the U3Si2. This proposal seeks to measure the mechanical properties of U3Si2 in the temperature range (RT-700 ºC) using small scale mechanical testing (microcantilever) in order to increase the mechanical data available for modeling efforts. These results would add to the knowledge of the mechanical behavior of U3Si2 in a reactor core which would improve the predictive modeling in the MARMOT-BISON-MOOSE framework and increase the ability to evaluate this fuel as potential accident tolerant fuel for the nation’s current nuclear infrastructure. The work aims to measure the elastic modulus, fracture stress and evaluate the deformation of U3Si2 using microcantilever testing in the temperature range of RT-700 ºC. |
| Award Announced Date | 2019-05-14T17:02:33.983 |
| Awarded Institution | Argonne National Laboratory |
| Facility | Intermediate Voltage Electron Microscopy (IVEM)-Tandem Facility |
| Facility Tech Lead | Peter Hosemann, Wei-Ying Chen |
| Irradiation Facility | None |
| PI | David Frazer |
| PI Email | [email protected] |
| Project Type | RTE |
| RTE Number | 1793 |