Effective primary radiation damage model parameters for neutron irradiation experiments

Abstract

Neutron irradiation damage is a key factor that needs to be studied for materials employed in nuclear systems. The athermal recombination-corrected displacement per atom (arc-dpa) model has been recently proposed for improving the prediction of the primary radiation damage of materials. Using neutron irradiation experimental data, the present work investigates the arc-dpa model parameters for various materials. The adjusted arc-dpa model gives calculation results consistent with measured data within ∼1σ experimental uncertainty. In addition to the optimization of parameters against experimental data, the 1σ reasonable regions of the two model parameters are determined for neutron irradiation damage. Based on the asymptotic value of one of the model parameters, an effective threshold displacement energy Ed∞ is defined. It is observed that Ed∞ is not sensitive to the widely used average threshold displacement energy Ed. The classical Norgett-Robinson-Torrens (NRT)-dpa model using Ed∞ is consistent with the arc-dpa model for neutron irradiation-induced displacement damage.