A phenomenological model for 'at-sea' marine immersion corrosion of mild steel

摘要

A comprehensive model for the prediction of likely 'general' corrosion loss of mild steel under fully aerated 'at-sea' immersion corrosion conditions is proposed herein. It is a non-linear function of time, controlled by distinctly different corrosion process phases - kinetic, diffusion and anaerobic. The model is parameterized and calibrated using interpreted literature data. Only actual field data are employed. It is shown that average seawater temperature has a strong influence on each corrosion phase. The influences of other factors such as salinity, water temperature at first immersion and the season, surface preparation and velocity effects and the effect of steel composition, essentially eliminated by the fully aerated 'at-sea' condition, are important in practice.