Numerical simulations of displacement cascades in irradiated with intensive neutron flux iron

Numerical calculations of the radiation defects created in iron irradiated by fast neutrons (E > 0.1 MeV) were carried out. The total atom damages in iron at a neutron flux of 1.4x1015 n/cm2s-1 were determined to be 37.2 displacements per atom (dpa) per full power year (fpy). The helium concentration of 375 appm/fpy was obtained in irradiated iron for the same total neutron flux. A multi-scale numerical model has been developed in order to obtain better values for the neutron damages and the concentration of impurities. Using this approach the concentration of Fe, Mn and Cr isotopes as well as the concentration of helium and tritium has been determined as a result of the fast neutron irradiation.