[1J05-08] Corrosion, Electrochemistry, Radiolysis 1

[1J06] Electrochemical Corrosion Potential Calculation Model for Nickel Base Alloy 182 in High Temperature – High Purity Water

*Yoichi Wada¹, Kazushige Ishida¹, Masahiko Tachibana¹, Ryosuke Shimizu² (1. Hitachi, Ltd., 2. Hitachi-GE Nuclear Eenrgy, Ltd.)

Keywords:ECP, Nickel base alloy, Boiling Water Reactor, Polarization curve, Stress Corrosion Cracking

It is important to calculate electrochemical corrosion potential (ECP) of nickel base alloy weld metal 182 (alloy 182) for management of stress corrosion cracking for a BWR. An ECP calculation model for Alloy 182 has been developed based on measured polarization curves in high temperature - high purity water. The cathodic polarization curves by oxygen concentration for alloy 182 could be reproduced with the developed model. Change in Tafel's parameters for alloy 182 with oxygen concentration could be explained. Also calculated ECPs for alloy 182 could agree with measured data in the wide range of oxygen concentration. The ECP of alloy 182 in the oxygen environment in a BWR environment can be calculated with the determined electrochemical reaction parameters.