Electrochemical corrosion studies of ultrafine-grained aluminium alloy EN AW-6063



The electrochemical corrosion behaviour of ultrafine-grained EN AW-6063 processed by equal-channel angular pressing (ECAP) was investigated in a 0.01 M sodium chloride solution for different numbers of ECAP-passes. Some of the ECAPed samples were additionally heat treated and show better corrosion resistance in their potentiodynamic polarisation behaviour than the samples without the heat treatment. Investigations of the surface topology indicate more uniform corrosion when compared to the initial state without ECAP and heat treatment. The results of the microscopic observations confirm that the corrosion behaviour is improved by increasing the number of ECAP-passes and by additional heat treatment.