Microelectrochemical investigation of the effect of cathodic polarisation on the corrosion resistance of 304L stainless steel in a 1 M NaCl solution

304L stainless steel was cathodically polarised in a 1 M sodium chloride solution using a microcapillary electrochemical droplet cell. During the cathodic polarisation the produced hydrogen atoms penetrate into the sample and accumulate at sites of the steel surface. We observed that the pitting potential (E-pit), the anodic current density (I-corr) and the corrosion potential (E-corr) of the polarised steel are strongly influenced by the applied cathodic potential and therefore by the amount of charged hydrogen atoms which penetrate into the sample. Local electrochemical impedance spectroscopy (LEIS) using different applied cathodic potentials shows lower corrosion resistance for cathodically polarised steel and reveals a different behaviour on a microscale level