Abstract:Electrochemical noise (EN) data were measured during the dissolution and passivation of an Cu-Pb anode at 65 °C in 1 L industrial electrolyte containing 2 mg of gelatine and 4 mg of thiourea. The EN data corresponding to three stages or regions of active, pre-passive and passive on chronopotentiogram curve were analyzed by wavelet transform technique. The results reveal the pitting type of localized corrosion form during both active and pre-passive stages under a constant current density of 215 mA/cm². During the passive stage, a general corrosion form accompanied by oxygen evolution was observed.

Key words: electroctrochemical noise; corrosion; wavelet transform; copper; additives; chronopotentiometry