Investigating effect of dose rate on microstructure evolution in 800H alloy at high doses

Principal Investigator

Name:: Xingyu Liu
Email:: [email protected]
Phone:: (208) 526-6918

Awarded on Monday, September 23, 2024

Project Code:: 24-5164
Call:: FY 2024 RTE 3rd Call

Team Members:

Name:	Institution:	Expertise:	Status:
Xing Wang	Pennsylvania State University	APT, Radiation Damage, Rate Theory, TEM	Faculty
Arthur Motta	Pennsylvania State University	Amorphization, Cladding, Corrosion, Hydrides, Intermetallic, Material Characterization, Material Degradation, Radiation Damage, Synchrotron, Zirconium, Zirconium Alloys	Faculty

Project Summary

The proposed Rapid Turnaround Experiment (RTE) aims at elucidating the effect of dose rate on precipitate dissolution and the effect of local chemistry on the cavity formation at high doses. The microstructure evolution observed during in-situ dual ion irradiation will bridge the knowledge gap between neutron irradiation damage and dual ion irradiation damage at high doses. By leveraging the newly established in-situ dual ion irradiation capability in Intermediate Voltage Electron Microscope (IVEM) facility at Argonne National Laboratory, we aim to unravel the interactions between radiation-induced precipitates and cavities and establish fundamental understandings of dose-rate effects on defect evolution in 800H alloys, thus enabling more accurate emulation of neutron damage using accelerated ion irradiation.

Relevance

A significant obstacle to accelerating the deployment of advanced nuclear reactors and extending the operation of existing ones is the lack of sufficient data on the performance of core structural materials at high doses. To expedite the qualification process for promising structural materials, faster irradiation methods, such as heavy ion irradiation, are essential. However, accurately emulating neutron damage with ion irradiation presents challenges due to gaps in understanding the mechanisms of microstructure evolution at various doses and high dose rates.

To address this knowledge gap, we will utilize in-situ dual-ion irradiation to characterize defect evolution in 800H alloy at different dose rates and high doses. 800H is a promising austenitic steel for both light water reactors and advanced reactors, and it serves as a benchmark material for understanding fundamental mechanisms. Our focus will be on cavities and precipitates, two key defect structures that significantly impact material performance. The in-situ irradiation will allow us to correlate the kinetics of these defects both spatially and temporally, providing insights into the coupled effects of dose rates on defect evolution.

Our research will directly support two of the DOE-NE goals:

Enable the continued operation of existing U.S. nuclear reactors.

Enable the deployment of advanced nuclear reactors.

The findings from this study will also support an ongoing NEUP IRP project that aims to emulate neutron damage using dual-ion irradiation.