[2C16-21] Nuclear Materials

[2C17] Development of accident tolerant control rod

(7) Compatibility between novel neutron absorbers and molten fuel at high temperature

*Kinya Nakamura¹, Hirokazu Ohta¹, Masahide Takano² (1. CRIEPI, 2. JAEA)

Keywords:accident tolerant control rod, neutron absorber, rare earth element, recriticality, improved safety

CRIEPI is working on the development of long-life, accident tolerant control rods that can make advanced use of LWR fuel and improve core safety. The results of the high-temperature reaction tests between the novel neutron absorber (Eu,Hf)Ox and the molten fuel (U,Zr)O2 showed that Eu and U were homogeneously mixed at the molten core temperature of 2600℃. This suggests that ATCR has the ability to significantly reduce the risk of recriticality not only during the accident progression process but also during decommissioning after the accident.