Electrochemical properties and corrosion inhibition of AA6061 in tropical seawater

The corrosion inhibition of aluminum and its alloys is the subject of tremendous technological importance due to the increased industrial applications of these materials. This study reports the results of potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) on the corrosion inhibition of AA6061 aluminum alloys in seawater using sodium benzoate as an inhibitor. The electrochemical measurements for aluminum alloys in seawater after varied immersion period showed that the presence of sodium benzoate significantly decreases the corrosion currents densities (i(corr)), corrosion rates and double layer capacitance (C-dl), as simultaneously increase the values of polarization resistance (R-p). Charge transfer process and development of thin film on the specimen have been proven by morphology study using SEM. (c) 2007 Elsevier B.V. All rights reserved.