The aim of this work is to evaluate the corrosion resistance of the API SL X52 steel in soil from the Serra do Ouro Branco, Minas Gerais,
Brazil. The electrolytes studied were an aqueous extract of the soil and a synthetic solution of the soil medium. The electrochemical
techniques used were Tafel analysis and electrochemical impedance spectroscopy. The semi-quantitative chemical analysis of
the soil was performed using X-ray Á uorescence spectroscopy. The steel samples, after Tafel analysis, were analyzed using the
scanning electron microscopy coupled with the energy dispersive spectrometry. The API steel showed a higher corrosion potential and
polarization resistance and a lower current density in aqueous extract of soil. The Nyquist diagrams show two capacitive arcs, with
two time constants.
KEY WORDS: Corrosion; Aqueous extract of soil; Electrochemical impedance spectroscopy; API SL X52 steel.