Corrosion of Weathering Steel under Light Illumination and Simulated Atmospheric Conditions

摘要

Earlier investigations have shown that corrosion products of weathering steel presented photovoltaiceffect under illumination. In this study, we explored the influence of chloride ions on this effect and therelated corrosion behavior. Open circuit potential, electrochemical impedance spectroscopy and Mott-Schottky plots were recorded on weathering steel surface treated with NaCl after 3 days exposure insimulated atmospheric condition under illumination. For comparison, similar study was also performedon the weathering steel surface without NaCl deposition. There was clearly photoelectrochemicalresponse difference between the samples. It was found that the defects concentration and electricconductivity of the corrosion products were higher due to the chloride ions migration, which waspromoted by incorporation of photo-generated holes under illumination. The detailed mechanism wasdiscussed in this study.