NSUF 17-CINR-13007: Irradiation of Advanced Neutron Absorbing Material to Support Accident Tolerant Fuel

A strong focus of the nuclear industry is to develop enhanced accident tolerant fuel (EATF) concepts. Extensive levels of funding are being spent industry-wide on development of these concepts with the goal to deploy lead assemblies by 2021. Deployment of EATF products supports Department of Energy’s (DOE) Office of Nuclear Energy’s (NE) mission to sustain the safety of current reactors.Once EATF cladding and fuel concepts are utilized in reactors, the limiting components during Design Basis Accidents (DBAs) and Beyond Design Basis Accidents (BDBAs) will be the control components. Current absorber materials have proven insufficient at providing reactivity control during the Three Mile Island and the Fukushima Daiichi accidents. During DBA conditions at peak fuel rod cladding temperatures, control rod temperatures are predicted to be high enough that current absorber materials, which form low-melting eutectics with the control component cladding materials, will melt with vaporization of portions of the material. Additionally, the densities of these materials prevent inter-mixing of the material with molten material formed during a full core melt-down.The current neutron absorbing materials used in the nuclear industry are silver-indium-cadmium (AIC) and boron carbide (B4C). Alternative neutron absorbing materials have been developed which do not form low melting eutectics with cladding materials and are stable to temperatures much higher than those predicted during severe accident conditions. These replacement materials have been designed such that they are nearly transparent changes to the operating reactor, targeting equivalent neutronic worth and control rod drop times. To replace AIC bars, a combination of two types of pellets is necessary to achieve this objective. By utilizing pellets of both samarium hafnate and hafnium carbide, a control component can be designed with similar neutronic worth and control rod drop times. Similarly, B4C pellets can be replaced by europium hafnate pellets with minimal impact to control component performance. The out of pile testing program on these materials is underway, but must be complemented by in-pile irradiations to quantify the irradiation-induced swelling characteristics of the new absorber materials. Once the performance of the absorber materials are demonstrated under irradiation, these materials can be deployed to the commercial nuclear industry, improving accident tolerance of the current operating fleet of nuclear reactors.

Additional Info

Field	Value
Award Announced Date	2024-01-16T09:38:50.873
Awarded Institution	Areva NP Inc.
Facility Tech Lead
Irradiation Facility
PI	Jacqueline Stevens
PI Email	[email protected]
Project Type	CINR
RTE Number	3054