Molecular dynamics simulations of the radiation damage in α-iron

The method of molecular dynamics simulations has been used to investigate the development of displacement cascades in iron. Radiation damage caused by fast neutrons or ions results from the creation of energetic primary knock-on atom (PKA), which in turn produces displacement cascades. Cascades of 2 and 4 keV in energy have been simulated by molecular dynamics code, MOLDY, in α-iron at 290 .deg. C. In order to investigate the damage evolution processes, the changes in cascade morphology during the collisional process are observed. And, we quantitatively analyzed the primary damage state, of which two parameters are taken into account: (1) the number of isolated point defects and (2) the distribution of point defect clusters formed following the collisional process. The simulation reveals that interstitials tend to form clusters whereas vacancies remain as isolated defects in α-iron