Equivalent Circuit for EIS Study on Rusted Marine Cast Iron Artifacts

Abstract

EIS technique was employed to study corrosion of the rusted cast iron artifacts in seawater. The impedance spectra show characteristic of diffusion in the complex plane. At low frequencies, the complex impedance data trace out straight lines with less slopes with increasing immersion time. Equivalent circuit provides useful information that the rusted iron undergoes severe corrosion in seawater in the presence of porous scale. SEM results reveal the morphologies of the three main iron oxyhydroxides.