The computation of displacement damage cross sections of silicon, carbon and silicon carbide for high energy applications

Abstract

The polyatomic material SiC is being considered as a potential structural constituent for applications in advanced high temperature nuclear reactors. The radiation damage in these materials due to neutron irradiation requires to be assessed accurately to predict their residence time in these reactors. It is generally quantified by a parameter called displacement per atom (dpa). Knowledge of dpa cross section is essential to compute its dpa rate in a known neutron flux field. Nowadays methods like Monte Carlo and Molecular Dynamics are used to compute dpa cross sections. In fast reactors, the dpa model given by Norgett, Robinson and Torrens (NRT-dpa) is used for design studies. In this paper, we discuss the methodology of computing dpa cross sections of SiC by using the NRT model based dpa cross sections of constituent elements (Si and C) from a more recent evaluated nuclear data library called ENDF/B-VII.1. The contributions of all important partial reactions including radiative capture are considered for the calculation of NRT-dpa by developing an indigenous code. Our results are compared with the published values.