NEUTRON ABSORBER FOR NUCLEAR REACTOR CONTROL RODS Russian patent published in 1998 - IPC

FIELD: nuclear power engineering; pressurized-water reactors. SUBSTANCE: burning-out neutron absorber possessing high corrosion and radiation resistance in high- condition water (temperature 350 C, pressure 200 MPa) retains most high radiation-resistant face-centering cubic structure of fluorite type within wide range of compounds. To this end, it has, in addition, niobium oxide in its composition and is synthesized by direct fusion of mixture of source oxide components with following proportion of ingredients, mass percent: dysprosium oxide - 12-82; hafnium oxide - 0.5-85; niobium oxide - 0.5-20; when dysprosium oxide content exceeds 78%, niobium oxide content should be minimum 5 mass percent. EFFECT: improved corrosion and radiation resistance at high water temperatures and pressures, improved stability of face-centering structure. 1 tbl