NSUF 18-1561: Grain Size Effects on He and Xe behavior in UO2 and ThO2

It has been reported that radiation tolerance of materials increases as the grain size approaches the nanoscale, suggesting that grain boundaries act as defect sinks and hence favor defect annihilation. However, there is a lack of data concerning the performances of UO2 and this work aims to fill that gap, in particular for what concerns low grain sizes. An innovative aspect is indeed the concept of submitting to the same radiation conditions, which were reported in previous similar experiments, a series of samples which only differ for the grain size, removing any other possible reason for the enhanced radiation tolerance. Revealing grain size effects on radiation tolerance and rare gases Xe and He- retention in UO2 and ThO2 will be the main purpose of this study. The comparison between the microstructure features of UO2 and ThO2 under various doses and temperatures will shed light on both the dose and temperature effects on dislocation, bubble formation and evolution. This rapid turnaround project includes in situ TEM observation using IVEM-Tandem facility at ANL, experimental data analysis and final report, which will take about 9 months in total. The proposed research will be performed in about 2 weeks at ANL.

Additional Info

Field	Value
Abstract	It has been reported that radiation tolerance of materials increases as the grain size approaches the nanoscale, suggesting that grain boundaries act as defect sinks and hence favor defect annihilation. However, there is a lack of data concerning the performances of UO2 and this work aims to fill that gap, in particular for what concerns low grain sizes. An innovative aspect is indeed the concept of submitting to the same radiation conditions, which were reported in previous similar experiments, a series of samples which only differ for the grain size, removing any other possible reason for the enhanced radiation tolerance. Revealing grain size effects on radiation tolerance and rare gases Xe and He- retention in UO2 and ThO2 will be the main purpose of this study. The comparison between the microstructure features of UO2 and ThO2 under various doses and temperatures will shed light on both the dose and temperature effects on dislocation, bubble formation and evolution. This rapid turnaround project includes in situ TEM observation using IVEM-Tandem facility at ANL, experimental data analysis and final report, which will take about 9 months in total. The proposed research will be performed in about 2 weeks at ANL.
Award Announced Date	2018-09-17T12:05:14.52
Awarded Institution	None
Facility	None
Facility Tech Lead	Wei-Ying Chen
Irradiation Facility	None
PI	Thierry Wiss
PI Email	[email protected]
Project Type	RTE
RTE Number	1561