Electrochemical Impedance Modeling of the Passivity of Carbon Steel in Simulated Concrete Pore Water

The prediction of corrosion damage to times that are experimentally inaccessible by a large factor (e.g., to over 1000 years) is vitally important in assessing various concepts for the disposal of High Level Nuclear Waste. Such prediction can only be made using deterministic models, whose predictions are constrained to being “physically real” by the natural laws [conservation of mass, energy, charge and mass-charge equivalence (Faraday’s Law)]. In this paper, we describe the measurement of experimental data that will allow the deterministic prediction of damage to the carbon steel overpack of the super container in Belgium’s proposed Boom Clay repository by using the Point Defect Model to extrapolate damage to future times. We also describe an experimental program that is designed to generate values for various PDM parameters for the corrosion of carbon steel and stainless steel that will be required in making the damage predictions.