Laurus nobilis L. oil as green corrosion inhibitor for aluminium and AA5754 aluminium alloy in 3% NaCl solution

The influence of (30%, v/v) ethanolic solution of Laurus nobilis L. oil on the corrosion inhibition of aluminium and AA5754 aluminium alloy in 3% NaCl solution was studied by weight loss method, potentiodynamic polarization, and linear polarization method. The polarization measurements show that addition of this oil in concentrations ranging from 10 ppm to 50 ppm induces a decrease of cathodic currents densities. The results confirm that AA5754 alloy has better corrosion resistance in 3% NaCl solution than pure aluminium, while the oil investigated has better inhibition action on corrosion process of pure aluminium. The surface analysis via SEM techniques indicate that the active molecules from L nobilis L oil absolutely retard the pitting corrosion on the specimen surfaces. (C) 2012 Elsevier B.V. All rights reserved.