Abstract:The optimum corrosion protection potentials were examined for 5052-O Al alloy, which is mainly used in ships. Various electrochemical experiments were carried out and the surface morphologies of specimens were observed by scanning electron microscopy (SEM) in order to determine the optimum corrosion protection potential to overcome pitting, corrosion, stress corrosion cracking (SCC), and hydrogen embrittlement in sea water. An optimum protection potential range of -1.3 V to -0.7 V was determined under the application of an impressed current cathodic protection (ICCP) system. The low current densities were shown in the range of -1.3 V to -0.7 V in the electrochemical experiments and good specimen surface morphologies were observed after potentiostatic experiment.

Key words: aluminum alloy; corrosion; electrochemical characteristics; stress corrosion cracking; hydrogen embrittlement; sea water corrosion; cathodic protection