Atmospheric corrosion in subtropical areas: Statistic study of the corrosion of zinc plates exposed to several atmospheres in the province of Santa Cruz de Tenerife (Canary Islands, Spain)

A semi-empiric equation has been proposed in order to predict corrosion rate values of zinc samples previously exposed to subtropical atmospheres. Samples were exposed during four years to the action of different atmospheres in 35 test sites distributed in the western islands of the Canarian Archipielago (Spain) located in front of the African continent. Corrosion rate has been obtained by lost of weight. Time of wetness (Tw) and deposition rates of atmospheric pollutants (SO2 and Cl−) have also been determined. Considering the meteorological data (SO2 and Cl− deposition rates) and corrosion rate values corresponding to three years of exposure, a semi-empiric equation that predicts, with good agreement, the corrosion rate of zinc exposed to this subtropical atmosphere, has been proposed. The validity of the equation has been tested comparing the equation predictions with experimental data corresponding to samples with four years of exposure. Both experimental and predicted data showed a good agreement.