Meso-scale Magnetic Signatures for Nuclear Reactor Steel Irradiation Embrittlement Monitoring
EMSL Project ID
49202
Abstract
This project is funded by the Office of Nuclear Energy under the Enabling Technologies program. Verifying the structural integrity of passive components in light-water and advanced reactors will be necessary to ensure safe, long-term operations of the existing U.S. nuclear fleet. This objective can be achieved through nondestructive condition monitoring techniques, which can be integrated with plant operations to quantify the ‘state of health’ of structural materials in real-time. While nondestructive methods for monitoring many classes of degradation (such as fatigue or stress corrosion cracking) are relatively advanced, this is not the case for degradation because of irradiation. The development of NDE technologies for these types of degradation will require advanced materials characterization techniques and tools that enable comprehensive understanding of nuclear reactor material microstructural and behavioral changes under extreme operating environments. Irradiation-induced degradation of reactor steels causes changes in their micro-magnetic properties. One example is the irradiation-induced formation of Cr precipitates that have been observed in Fe-Cr-Ni steels. These precipitates cause changes in bulk magnetic NDE signatures (e.g., major and minor hysteresis loops). We hypothesize that these property changes can be measured using micro-magnetic methods included magnetic force microscopy (MFM). A major part of this project therefore involves using MFM imaging and other techniques to support computational models. This will provide a greater understanding of the correlations between magnetic properties and radiation-induced damage in structural reactor metals. A new or improved understanding of phase transformation and structural evolution at interfaces under ion irradiation will be gained. Exploration of nuclear waste forms will provide underpinning physical and chemical sciences for the formation of new crystalline phases and their stability under extreme conditions. The outcome of work is expected to have a significant impact on the structural materials for designs of future nuclear energy systems and radiation detection and monitoring devices.
Project Details
Start Date
2016-01-06
End Date
2016-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members
Related Publications
Xu K ,Schreiber D K,Li Y ,Johnson B R,McCloy J S 2017. "Effect of defects, magnetocrystalline anisotropy, and shape anisotropy on magnetic structure of iron thin films by magnetic force microscopy" AIP Advances 7(5):056806. 10.1063/1.4976580