Tensile and low cycle fatigue properties of different ferritic/martensitic steels after the fast reactor irradiation ‘ARBOR 1’

In the irradiation project ‘Associated Reactor Irradiation in BOR 60’, named ‘ARBOR 1’, tensile and low cycle fatigue specimens of reduced activation ferritic/martensitic steels have been irradiated in a fast neutron flux (>0.1 MeV) of 1.8 1015 n/cm2 s and with direct sodium cooling at a temperature <340 °C to 15 and ∼30 dpa. With increasing irradiation damage the tensile behaviour of, e.g. EUROFER 97, leads to hardening in combination with a dramatic reduction in uniform strain, but with a considerable total strain. The low cycle fatigue behaviour of all examined ferritic/martensitic steels, like EUROFER 97, F82H mod. and ODS-EUROFER 97 with 0.5% Y2O3, show at total strains below 1% an increase of number of cycles to failure, due to irradiation hardening.