Atmospheric corrosion of AISI-1020 carbon steel in a very aggressive coastal zone of Havana, Cuba. Determination of corrosivity category using three ways of assessment

Abstract

The Cuban coastal line is reported to be one of the most aggressive in the world. Three ways to estimate corrosivity category of the atmosphere were considered. The influence of meteorological parameters on chloride deposition rate $\left(S_d\right)$ in saline solution form was considered as a first way. Corrosion rate $\left(r_{\text{corr}}\right)$ calculated by dose response function is considered a second way. It was confirmed that atmospheric corrosion of AISI-1020 carbon steel is influenced by $S_d$ and $P_d$ in salt solution form. A critical $S_d$ level from which $r_{\text{corr}}$ could increase was estimated. The presence of typical crystalline phases of carbon steel confirmed that formation mechanism led to cracking of the corrosion products layer. It justified the increase of r_corr as a function of time until reaching a very high (C5) corrosivity category as the third assessment way. $r_{\text{corr}}$ was predicted up to 20 years of exposure. A correspondence between the three assessment ways existed.