Burst properties of irradiated oxide dispersion strengthened ferritic steel claddings

The effects of fast neutron irradiation on the burst properties of oxide dispersion strengthened (ODS) ferritic steel claddings which were previously manufactured by warm working as the first trial cladding tube manufacturing in Japan Nuclear Cycle Development Institute, were investigated. The samples were irradiated in the experimental fast reactor JOYO using the core material irradiation rig (CMIR) at temperatures between 723 and 878 K to fast neutron fluences ranging from 2.1 to 4.2×1026 n/m2 (E>0.1 MeV). The burst tests were conducted on a total of four irradiation conditions. The result of burst tests showed that the burst strength of the irradiated claddings was higher than that of unirradiated at the test temperatures up to 873 K and that the diametrical strain just before rupture of irradiated specimens was almost similar to unirradiated one. It was suggested that there was no irradiation embrittlement under the irradiation conditions examined.