NSUF 15-591: Characterize Neutron Irradiated NF709 Stainless Steel Using Atom Probe Tomography

Austenitic stainless steel NF709 has been identified as one of the candidate structural materials for sodium-cooled fast reactors. However, the understanding on its irradiation response is very limited to date. Our preliminary results using high energy X-ray diffraction and TEM/STEM/EDS characterization show that the irradiation can induce a significant precipitate evolution in this alloy via dissolving the pre-existing Nb(C, N) precipitates and promoting new types of Ti/Cu enriched solute clusters. To fully understand irradiation effects on this alloy, it is proposed to further characterize the irradiated microstructure using APT by taking advantages of its exceptional elemental and spatial resolutions for chemical analysis. The completion of this study shall provide an unprecedented understanding on the fundamental mechanism of how the irradiation induced microstructural evolutions in this candidate alloy, and how they subsequently affect the material mechanical behavior under a thermal-mechanical loading which is currently under investigation through an ongoing NEET project.

Additional Info

Field	Value
Abstract	Austenitic stainless steel NF709 has been identified as one of the candidate structural materials for sodium-cooled fast reactors. However, the understanding on its irradiation response is very limited to date. Our preliminary results using high energy X-ray diffraction and TEM/STEM/EDS characterization show that the irradiation can induce a significant precipitate evolution in this alloy via dissolving the pre-existing Nb(C, N) precipitates and promoting new types of Ti/Cu enriched solute clusters. To fully understand irradiation effects on this alloy, it is proposed to further characterize the irradiated microstructure using APT by taking advantages of its exceptional elemental and spatial resolutions for chemical analysis. The completion of this study shall provide an unprecedented understanding on the fundamental mechanism of how the irradiation induced microstructural evolutions in this candidate alloy, and how they subsequently affect the material mechanical behavior under a thermal-mechanical loading which is currently under investigation through an ongoing NEET project.
Award Announced Date	2015-08-10T00:00:00
Awarded Institution	None
Facility	None
Facility Tech Lead	Yaqiao Wu
Irradiation Facility	None
PI	Yong Yang
PI Email	[email protected]
Project Type	RTE
RTE Number	591