Comparative analysis for the corrosion susceptibility of copper alloys in sandy soil

Abstract

Corrosion of copper alloys (copper, bronze and brass) in soil was evaluated at ambient temperature using various methods such as electrochemical impedance spectroscopy (EIS), polarization curves and Scanning Electron Microscopy (SEM) coupled with Energy Dispersive Spectroscopy microanalysis measurements. Three equivalent circuits were separately used to interpret the obtained impedance spectra. The EIS measurements indicated that the polarization resistance of all electrodes increases with increasing the immersion time. SEM showed a presence of three layers of corrosion products with various composition and morphology covering each electrode. In addition, it was found that at 20% of moisture content the R p values and the current density of all electrodes in the studied soil give the following order: copper > bronze > brass. Good consistency between the data obtained from EIS and PP measurements was observed.