Local electrochemical impedance spectroscopy has been successfully used to study the local
electrochemical process (e.g., localized corrosion in the form of pitting corrosion) and to identify coating
defects on a coated coupon. The measured data can be accurately analyzed by developing a physicochemical
process model for the local electrochemical impedance spectroscopy of a system.
Traditionally, the finite element method (FEM) has been employed to solve the physico-chemical model
of local electrochemical impedance spectroscopy. However, FEM is computationally expensive
because it requires very fine meshing of the domain. In contrast, the boundary element method (BEM)
significantly reduces computational time without compromising accuracy. In this paper, we present a
methodology to calculate local electrochemical impedance spectroscopy using BEM of a simple
system. The validity and efficiency of the methodology is established by comparing the local
electrochemical impedance spectra obtained from BEM and FEM for the simple system that consists of
a planar-electrode confined in a rectangular geometry. The surfaces adjoining the electrode and
sidewalls are assumed to be insulating, whereas the surface opposite to the electrode is assumed to
be conducting.
Keywords: local electrochemical impedance spectroscopy, localized corrosion, boundary element
method, finite element method, potential distribution