Survey of Primary Knock-on Atoms Characteristics and Radiation Damage in Stainless Steel Grade 316

The displacement of the atoms from their lattice sites is one of the results of neutron irradiation on materials. The primary knocked-on atoms spectrum and their angular distribution should be calculated for consideration of neutron radiation damage calculation. The AMTRACK program has been developed to calculate this information. This program extracts and analyzes information about the primary knocked-on atoms by using Ptrac output of the MCNPX code. In this study, Stainless Steel 316, one of the most important alloys in the reactor pressure vessel, is investigated. The material is irradiated by single energy neutrons of 1keV to 10MeV, the fraction of produced PKAs, their average energy, their maximum energy, and radiation damage value are calculated. The calculations are performed by using the neutron spectrum of the Bushehr reactor. Using this method, the amount of damage in the Bushehr reactor pressure vessel (for Stainless Steel 316) is equal to 7.2×10-22 (dpa/ fluence).