Synergistic Inhibition Effect of Sodium Oleate and Sodium Vanadate on the Corrosion of Pure Aluminum in NaCl Solution

Synergistic inhibition effect of sodium oleate and sodium vanadate on the corrosion of pure aluminum in NaCl solution has been investigated by open circuit potential, potentiodynamic polarization curve, and electrochemical impedance spectroscopy(EIS). Experiment results show that the pure aluminum has the lowest corrosion current density under the optimum technological conditions at room temperature, which can be expressed as follows: the 3.5wt.% NaCl solution contains two inhibitors of sodium oleate and sodium vanadium, and their mole concentration ratio is 1:2, solution pH value is 8.0 similar to 8.5. In addition, these two inhibitors have played the major role of corrosion inhibition at different stage respectively, which can be attributed to the formation of continuous phase on the surface of pure aluminum.