NSUF 22-4459: Atom probe and transmission electron microscopy studies on neutron irradiated FeCrMnNi Compositionally Complex Alloy

Designing fuel claddings and ducts in advanced fission reactors such as the sodium fast reactor (SFR) is a challenge that may be overcome by shifting away from conventional alloy design. Alloys with one to two primary metallic constituent elements, typically show severe deterioration in material properties, such as excessive void swelling, at hundreds of displacements per atoms (dpas) of irradiation dose. Compositionally complex alloys (CCA) feature multiple primary alloying elements in solid solution and are of particular interest for understanding how matrix composition determines radiation damage behavior. Indeed, recent studies have shown that in addition to promising material properties, these alloys may resist extended defect formation under irradiation. The project focuses on the characterization of neutron irradiated CCAs in the FeCrMnNi system. Cr10Fe30Mn30Ni30 has been irradiated to 2 and 6 dpas at 300 and 500 ˚C at the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL). These irradiation conditions (dpa and temperature) are directly comparable to the in-study in the IVEM-Tandem facility. The 2 dpa irradiation capsule has been disassembled; the samples are available for nanoscale characterizations. TEM lamellae and atom probe tomography (APT) needles will be extracted by focused-ion beam. Potential void swelling and dislocation loop densities measurements will be performed using S/TEM micrographs, and Super-X energy dispersive X-ray spectroscopy (EDS) chemical maps and line-scans will be used along with APT to assess chemical segregation and short-range ordering induced by irradiation. This will represent the first characterization of neutron irradiation response of CCAs at reactor relevant temperatures.

Additional Info

Field	Value
Abstract	Designing fuel claddings and ducts in advanced fission reactors such as the sodium fast reactor (SFR) is a challenge that may be overcome by shifting away from conventional alloy design. Alloys with one to two primary metallic constituent elements, typically show severe deterioration in material properties, such as excessive void swelling, at hundreds of displacements per atoms (dpas) of irradiation dose. Compositionally complex alloys (CCA) feature multiple primary alloying elements in solid solution and are of particular interest for understanding how matrix composition determines radiation damage behavior. Indeed, recent studies have shown that in addition to promising material properties, these alloys may resist extended defect formation under irradiation. The project focuses on the characterization of neutron irradiated CCAs in the FeCrMnNi system. Cr10Fe30Mn30Ni30 has been irradiated to 2 and 6 dpas at 300 and 500 ˚C at the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL). These irradiation conditions (dpa and temperature) are directly comparable to the in-study in the IVEM-Tandem facility. The 2 dpa irradiation capsule has been disassembled; the samples are available for nanoscale characterizations. TEM lamellae and atom probe tomography (APT) needles will be extracted by focused-ion beam. Potential void swelling and dislocation loop densities measurements will be performed using S/TEM micrographs, and Super-X energy dispersive X-ray spectroscopy (EDS) chemical maps and line-scans will be used along with APT to assess chemical segregation and short-range ordering induced by irradiation. This will represent the first characterization of neutron irradiation response of CCAs at reactor relevant temperatures.
Award Announced Date	2022-06-14T07:22:50.153
Awarded Institution	None
Facility	None
Facility Tech Lead	Alina Zackrone
Irradiation Facility	None
PI	Adrien Couet
PI Email	[email protected]
Project Type	RTE
RTE Number	4459