Corrosion protection of soft‐cast steel in 1 M HCl with Araucaria heterophylla leaves extract

Abstract

AbstractThe mass‐loss, polarization tests, and electrochemical impedance spectroscopic strategies were applied to assess the inhibition performance of the environmentally friendly inhibitor Araucaria heterophylla leaves extract (AHLE) for soft‐cast steel corrosion safety in 1 M HCl at 300 ± 1 K. The environmentally friendly inhibitor creates a protective coat on soft‐cast steel that decelerates the corrosion process in acidic environments. The percentage inhibition effectiveness, corrosion current density, corrosion potential, cathodic and anodic Tafel slopes are being assessed. The outcomes of chemical and electrochemical research are almost similar. The inhibitor's inhibition activity was well illustrated by the AHLE adsorption on soft‐cast steel follows the Langmuir adsorption isotherm. According to the study, AHLE is a mixed kind of inhibitor. Experiments were conducted with varying inhibitor amounts and temperatures. The calculated values were in the range of −33.75 to −34.40 kJ/mol, which discloses the corrosion inhibitory action is exothermic and spontaneous. Scanning electron microscopy, Fourier transform infrared spectroscopy, and contact angle techniques were used to determine the association of the AHLE on the metal surface.