One-dimensional approach to modeling damage evolution in galvanic corrosion

• The 1D approach is fast and accurate when the underlying assumptions are satisfied.
• The IR drop and the galvanic current density influence the shape of the damage.
• The damage profiles capture the effects of changing the anode/cathode area ratio.
• The 1D approach is developed for several geometries.

A one-dimensional mathematical model is developed to describe time-dependent damage evolution in well-mixed (spatially uniform species concentrations) galvanic systems using an IR drop approach. An asymptotic procedure taking advantage of disparity in length scales (thin film approximation for the electrolyte thickness) is used to derive the model. Limitations that result from the reduction of dimension are described, along with an analysis demonstrating the ability of the 1D model to capture physical phenomena, such as area ratio effects. Computed potential, current density, and corrosion damage profiles are compared and verified with experimental data available in the literature and 2D galvanic corrosion simulations. Fully derived governing equations for several different 1D geometries are presented.