Corrosion inhibition of aluminium–brass in 3.5% NaCl solution and sea water

Electrochemical characteristics of Al–brass are investigated in both 3.5% NaCl and sea water. At active potential, the alloy is dissolved directly or through an adsorbed metastable CuCl layer. At higher applied anodic potential, the active–passive transition leads to the formation of a thicker and more stable CuCl salt layer. With further increase in the anodic potential, the formation of CuO and/or Cu(OH)2 will take place. The inhibition of the corrosion process is studied by adding SDBS, DPh(EO)9, and LAPACl as anionic, nonionic, and cationic surfactants. It is found that the inhibition efficiency increases in the following order SDBS>LAPACl>DPh(EO)9, and increases with increasing their concentrations.