Electrochemical corrosion potential models for boiling-water reactor applications

The electrochemical corrosion potential (ECP) of stainless steel (SS) was measured under simulated boiling-water reactor (BWR) coolant circuit conditions using a rotating cylinder electrode (RCE). Based upon those measurements, an empirical model was developed to predict ECP of structure materials in a BWR primary circuit as a function of hydrogen (H-2), oxygen (O-2), and hydrogen peroxide (H2O2) concentrations in the reactor coolant and of the waterflow velocity. Results of ECP modeling using the H-2, O-2, and H2O2 concentrations calculated by the radiolysis model were compared to internal ECP data obtained in an operating reactor.