Estimation of Radiation Damage to Inconel X-750 Spacers in Wolsung CANDU Reactors

Abstract

In this paper, we have estimated radiation damage to Inconel X-750 spacers in Wolsung CANDU reactor. Two damage parameters are of our interest, which are the displacement damage and the transmutation gas production. Basically, we used the SPECTER code in estimating radiation damage in terms of displacement damage (dpa) and transmutation gas production (appm). Also, radiation damage caused by the Ni two-step reactions was taken into account, which includes the displacement damage from recoil atoms and the gas production. The analysis was performed on four spacers located axially along a fuel channel. After 20 EFPY (Effective Full Power Year), the gas production from Ni-reaction is predominant, whereas the displacement damage due to recoil atoms from Ni-reaction accounts for over 30% out of total displacement damage.