Estimation of Corrosion Potentials in the Cores of Light Water Reactors

Abstract A mixed potential model (MPM) has been developed for calculating electrochemical potential (ECP) data for Boiling Water Reactor (BWR) in-vessel components and recirculation piping using compositional data obtained from radiolysis models. The calculated component ECPs for the Duane- Arnold BWR are in good agreement with limited in-plant data. The data suggest that hydrogen water chemistry (HWC) will be effective in protecting the lower plenum and recirculation system of this reactor against IGSCC, but that it will be ineffective in protecting other in-vessel components, (e.g. the upper plenum) unless the kinetics of the redox reactions on the steel surfaces can be modified.