Dysprosium titanate as an absorber material for control rods

Disprosium titanate is an attractive control rod material for the thermal n eutron reactors. Its main advantages are: insignificant swelling. no out-ga ssing under neutron irradiation, rather high neutron efficiency, a high mel ting point (similar to 1870 degrees C), non-interaction with the cladding a t temperatures above 1000 degrees C, simple fabrication and easily reproces sed non-radioactive waste. It can be used in control rods as pellets and po wder. The disprosium titanate control rods have worked off in the MIR react or for 17 years, in VVER-1000 - for 4 years without any operating problems. After postirradiation examinations this type of control rod having high li fetime was recommended for the VVER and RBMK. The paper presents the examin ation results of absorber element dummies containing dysprosium titanate, i rradiated in the SM reactor to the neutron fluence of 3.4 x 10(22) cm(-1) ( E > 0.1 MeV) and, also, the data on structure, thermal-physical properties of dysprosium titanate. efficiency of dysprosium titanate control rods. (C) 2000 Elsevier Science B.V. AII rights reserved.