NSUF 11-327: Study of the Microstructure of Irradiated CeO2 by Advanced Microscopy Techniques

The rapid turnaround experiment is to clarify the microstructure of irradiated polycrystalline CeO2, a surrogate material for UO2. To simulate fission fragments damage, 150 keV Kr at Argonne National Laboratory and 150 keV Xe at Los Alamos National Laboratory were used to irradiate polycrystalline CeO2 bulk and film samples with various grain sizes. The TEM samples of CeO2 before and after irradiation tests were prepared by ion-milling and focused ion beams at University of Wisconsin. The 300 kV Tecnai TF30-FEG TEM at Idaho National Laboratory (INL) will be used to reveal the microstructure of polycrystalline CeO2 before and after Kr and Xe irradiation. Black dot defects at size of about 1 nm will be examined using weak beam dark field imaging. Dislocation loops and dislocation segments or dislocation networks will be examined and the Burgers vector will be analysed. Cavities or bubbles in the grain and at grain boudanry (GB) will also be investigated. In addition, GB type (twin, low angle, high angle) and GB chemistry will be revealed by high-resolution TEM and STEM/EDS. The comparison between the microstructure features of CeO2 with various grain size and GB type will shed light on the GB effect on defect evolution and bubble formation under irradiation. Characterization of GB chemistry will provide essential information for understanding the thermal transport propeties in CeO2. The experimental microstucture characterization is to provide a fundamental foundation for the atomic-level modelings, which are conducted at INL, Florida State University and University of Florida. This rapid turnaround project includes TEM sample preparation, TEM/HRTEM/STEM characterization, experimental data analysis and final report, which will take about 5 months in total. The microstructure characterization by Tecnai TF30-FEG TEM at INL will take about 1-2 weeks in September and November.

Additional Info

Field	Value
Abstract	The rapid turnaround experiment is to clarify the microstructure of irradiated polycrystalline CeO2, a surrogate material for UO2. To simulate fission fragments damage, 150 keV Kr at Argonne National Laboratory and 150 keV Xe at Los Alamos National Laboratory were used to irradiate polycrystalline CeO2 bulk and film samples with various grain sizes. The TEM samples of CeO2 before and after irradiation tests were prepared by ion-milling and focused ion beams at University of Wisconsin. The 300 kV Tecnai TF30-FEG TEM at Idaho National Laboratory (INL) will be used to reveal the microstructure of polycrystalline CeO2 before and after Kr and Xe irradiation. Black dot defects at size of about 1 nm will be examined using weak beam dark field imaging. Dislocation loops and dislocation segments or dislocation networks will be examined and the Burgers vector will be analysed. Cavities or bubbles in the grain and at grain boudanry (GB) will also be investigated. In addition, GB type (twin, low angle, high angle) and GB chemistry will be revealed by high-resolution TEM and STEM/EDS. The comparison between the microstructure features of CeO2 with various grain size and GB type will shed light on the GB effect on defect evolution and bubble formation under irradiation. Characterization of GB chemistry will provide essential information for understanding the thermal transport propeties in CeO2. The experimental microstucture characterization is to provide a fundamental foundation for the atomic-level modelings, which are conducted at INL, Florida State University and University of Florida. This rapid turnaround project includes TEM sample preparation, TEM/HRTEM/STEM characterization, experimental data analysis and final report, which will take about 5 months in total. The microstructure characterization by Tecnai TF30-FEG TEM at INL will take about 1-2 weeks in September and November.
Award Announced Date	2011-09-26T00:00:00
Awarded Institution	None
Facility	None
Facility Tech Lead	Alina Zackrone, Yaqiao Wu
Irradiation Facility	None
PI	Lingfeng He
PI Email	[email protected]
Project Type	RTE
RTE Number	327