Plant extracts of Garcinia indicaChoisy, Terminalia chebulaRetz.andCoriandrumsativumL.were investigated for their efficiency in inhibiting the corrosion of aluminum and 6063 aluminum alloy in sodium hydroxide medium. The techniques like weight loss and potentiodynamic polarizationwere employed. The inhibition was proposed to be the result of adsorption of constituents of extract, which was found to obey the Langmuir adsorption isotherm. The inhibition was assumed to be the formation of a protective inhibitor layer formed on the surface of material.
