Calculation of the effect of fission gas xenon on threshold displacement energy of $UO_2$ using molecular dynamics simulation

Abstract

For decades, Uranium Dioxide($UO_2$) has been a major nuclear fuel. The physical properties of high-burnup $UO_2$ are degraded due to irradiation in nuclear reactors. There were some studies using molecular dynamics simulation on Threshold Displacement Energy to evaluate the radiation resistance of $UO_2$, but none of those studies considered about Xenon, the richest fission gas element in the $UO_2$ matrix. In this study, the threshold displacement energy of Xe- inserted $UO_2$ cell is calculated in order to evaluate the influence of Xenon atoms on radiation resistance of $UO_2$. Additionally, the relationship of threshold displacement energy reduction and the distance between Xenon atoms and PKA Uranium atoms are modeled to investigate the average threshold displacement energy of the Xenon implanted $UO_2$ system.