EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

Inorganic inhibitors (mainly nitrites) have been traditionally used to control the corrosion of steel reinforcements without significantly changing the concrete properties. Their negative effects on the environment have led to the search of alternatives, such as nature-based green inhibitors extracted from plants. The successful use of some natural substances, such as ginger, orange peel and rice husk has been already reported.
This research focuses on the use of the extract of liquorice for this application. The effectiveness of the proposed inhibitor was studied by electrochemical techniques. Corrugated carbon steel bars formed by thermomechanical treatment were immersed in simulated non-carbonated pore solutions with chlorides. The corrosion performance of the reinforcements was characterized without inhibitor and after its addition to the testing solution. The electrochemical behavior was monitored by electrochemical impedance spectroscopy (EIS) and polarization curves. The possible mechanism of the proposed inhibitor was studied by scanning electronic microscopy (SEM) observations of the rebar surface and X-ray photoelectronic spectroscopy (XPS). This research was funded by European Union's Horizon 2020 research and innovation MSCA-IF-2019 programme under grant agreement No 892074 (NATCON project).