Effect of Alloy Composition on Atmospheric Corrosion of Weathering Steel

A reliable method of predicting the thickness loss of weathering steel due to corrosion is currently unavailable. Corrosion loss depends significantly on the service life of the structure, the corrosive nature of the environment, and the alloy content of the steel. Therefore, a prediction method accounting for these factors should be possible. Models showing the effects of five alloying elements (copper, nickel, chromium, silicon, and phosphorus) on thickness loss in three environments (rural, industrial, and marine) are provided in this paper based on a comprehensive database. The models result in correlation coefficients higher than 0.95. The effects of the alloying elements indicated by the models show that failure to properly account for the alloying elements can yield as much as 20% error in thickness loss. The model can be integrated with existing service life models to forecast a thickness loss estimate for a required design life.