Corrosion Inhibitors: Effect on Aluminum Alloys

Abstract

Aluminum alloys are less corrosion resistance compared to the pure aluminum. The less corrosion resistance of the aluminum alloys results from trading their mechanical strength and stability with their corrosion resistance. Aluminum alloys show inhibition in alkaline, acidic, neutral chloride free, and chloride media. This study covers studies done on different inhibitors used in corrosion inhibition of aluminum alloys in various media. Generally, the inhibition efficiency of the inhibitors increases with increase in the concentration of the inhibitors. The inhibition efficiency also depends on the characteristic of the inhibitor; whether it is a mixed-type, anodic, or cathodic inhibitor. The experimental data fit in Langmuir adsorption isotherm indicates physical adsorption, while Gibb’s free energy values show that aluminum alloys’ corrosion inhibition is by spontaneous adsorption process. The addition of chloride in alkaline solution improves corrosion inhibition of aluminum alloys.