Mango peel extract as a green inhibitor in the corrosion of reinforced concrete

Chloride-induced corrosion of reinforcing steel embedded in concrete is a problem that causes the elements to lose their physical and mechanical properties and can lead to premature failures in civil works. This research article analyses the effectiveness of the green corrosion inhibitor in cement paste through the ethanolic extract of mango peel. The materials were dosed with the inhibitor added to the mixing water and the mechanical properties of the material were analysed by manufacturing cylindrical test specimens. To understand the corrosion phenomena, cubic samples were prepared and immersed in a 3 % sodium chloride (NaCl) solution for 365 days, simulating a highly aggressive chloride-ion environment. Electrochemical techniques such as half-cell potential (HCP), electro­chemical noise (EN), linear polarization resistance (LPR) and electrochemical impedance spectroscopy (EIS) are applied. The experimental results showed that the green corrosion inhibitor reduced the mechanical properties of concrete by 21.28 % compared to the blank, but a positive effect was observed in the corrosion evaluation. Initially, the inhibitor delayed the onset of corrosion, as indicated by high electrochemical noise and linear polarization resistance values due to the formation of a film of organic compounds present in the inhibitor extracts that acted on the active sites on the steel surface.