Mojtaba Esmailzadeh

This study investigates the effects of natural inhibitors (pomegranate juice, algae extract and tomato juice) on the corrosion resistance of titanium (grade 2) and magnesium alloys (AZ31). After sample preparation, corrosion tests were conducted using a potentiostat, employing Electrochemical Impedance Spectroscopy (EIS), and Potentiodynamic Polarization (PDP) tests. Two electrolytes were tested: a solution 3.5% NaCl and a solution 0.5M NaOH. All the tests were performed with 5% of inhibitor and with the reference solution. Also, inhibition efficiency was calculated on the base of PDP tests. The study found that pomegranate juice can act as good corrosion inhibitor for titanium and magnesium alloys in aqueous solutions 0.5M NaOH. This was demonstrated by the increase in the corrosion potential and impedance modulus and decrease in the corrosion current density after the addition of pomegranate juice to the solution. However, in a 3.5% NaCl solution, the efficacy of pomegranate juice was less pronounced, probably due to the high aggressivity of the electrolyte. Tomato juice and algae extract have instead shown very low inhibition effect in all the tested conditions.