Annual and long-term prediction of the atmospheric corrosion of metals

Abstract

The atmospheric corrosion of metals is known to be a discontinuous electrochemical process which takes place only when the metallic surface is wet or moistened by different meteorological phenomena (rain, humidity condensation, fogg, etc.). The magnitude of atmospheric corrosion would be relatively low if it were not for the presence of certain pollutants in the atmosphere, mainly sulphur dioxide (anthropogenic pollutant) and marine chlorides (natural pollutant). The literature contains different models for predicting the atmospheric corrosion of metals over short periods (generally one year) and long periods (15, 20 or more years) of atmospheric exposure. In addition to the different meteorological factors (volume of precipitation, days of rain, relative humidity (RH), T, etc.), atmospheric SO₂ deposition rate and atmospheric salinity (Cl^-) appear as independent variables in all of these models.