Radiation damage analysis of the first generation VVER spent nuclear fuel casks

Abstract

Radiation damage can be assessed by displacements per atom (DPA). DPA calculations can be performed with flux conversion functions for iron or low alloy steels by ASTM or IRDFF standards. However, these standards cannot be applied for higher alloy steels or for materials with arbitrary chemical composition. In these circumstances, cross sections for arc-DPA and NRT-DPA definitions can be used. In the paper, the radiation damage analysis for determining DPA based on all available nuclear data is presented. The analysis was carried out for a first generation of VVER-440 dual purpose spent fuel cask. This spent fuel cask is one of the oldest cast ductile iron casks manufactured and its original lifetime will expire soon. Monte Carlo codes MCNP6 and Serpent 2 are both used for the radiation damage study to find out if radiation damage of the cask does not represent a major issue in its lifetime.