Defect production in α-iron irradiated by fission and fusion neutrons

We present the results of a molecular dynamics (MD) simulation of the damage production in iron under two irradiation conditions such as those in the commercial pressurized water reactors (PWR) and fusion power reactors. Two sets of neutron spectra include a commercial PWR neutron spectrum at the 0-T reactor pressure vessel position and a DT fusion reactor (ITER) first wall spectrum. The spectral average energy of the primary knock-on atoms has been obtained from the SPECTER code, which is 5.3 keV for PWR and 7.4 keV for ITER. These were used as input for the MD simulation in which cascades of 5.3 keV at 290 .deg. C and 7.4 keV at 500 .deg. C have been simulated and quantitatively compared. No significant difference was found in the primary damage state between the two conditions. The high dose rate, expected in the fusion reactor environments, may be the main source of radiation damage