Microelectrochemical Investigation of the Effect of Cathodic Polarisation on the Corrosion Resistance of 304L Stainless Steel in a 1 M NaCl Solution

摘要

L stainless steel was cathodically polarised in a 1 M sodium chloride solution using amicrocapillary electrochemical droplet cell. During the cathodic polarisation the produced hydrogenatoms penetrate into the sample and accumulate at sites of the steel surface. We observed that thepitting potential (Epit), the anodic current density (Icorr) and the corrosion potential (Ecorr) of thepolarised steel are strongly influenced by the applied cathodic potential and therefore by the amount ofcharged hydrogen atoms which penetrate into the sample. Local electrochemical impedancespectroscopy (LEIS) using different applied cathodic potentials shows lower corrosion resistance forcathodically polarised steel and reveals a different behaviour on a microscale level.