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Atmospheric corrosion level in tropical coastal zones is usually very significant.Corrosion control and preservation of infrastructure in these regions is very important to increase durability. Atmospheric corrosion of carbon steel, copper, galvanized steel, and aluminum was evaluated in a coastal industrial port zone located in a tropical island during 1 year. Samples were exposed at seven outdoor corrosion sites located at different distances from the sea. Main atmospheric pollutants, relative humidity, and air temperature were monitored during the exposure time. The existence of a combination between two of the most aggressive atmosphere types was determined (coastal-industrial and industrial-coastal). Changes in RH and temperature influenced 1462 |

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Atmospheric corrosion of low carbon steel exposed in a coastal tropical zone of Manabí, Ecuador, was determined. Specimens were exposed at six outdoor exposure sites located at different distances from the sea. The atmosphere is classified as coastal. Wind speed threshold for an increase in chloride deposition rate was determined. The behavior of chloride deposition rate versus distance from the sea is anomalous due to the presence of an estuary. Corrosion by weight loss was evaluated up to 1 year of exposure. Only a slight difference in atmospheric corrosion rate is noticed between wet and dry periods. Chloride deposition interaction with RH–temperature complex and with wind speed shows significant statistical influence on atmospheric corrosion of low carbon steel. Corrosivity category of the atmosphere high (C4) is the most predominant classification level in the zone. Prediction indicates corrosivity category high (C4) will remain up to 20 years of exposure. Different morphologies of corrosion products were identified by SEM. Lepidocrocite, goethite, magnetite, and akaganeite are the main crystalline phases determined by XRD. Protective ability index previously proposed for rust layers is not useful to apply in coastal sites.

This study focused on the application of electrochemical noise to assess the protection level of corrosion products formed on copper during relatively short exposure time in different outdoor atmospheres. Electrochemical noise, cathodic reduction measurements and gravimetric (mass loss) analysis were applied to copper samples exposed at urban and rural/industrial areas in Cuba for 4 months. Measurements of Electrochemical current noise indicated that the poorest protective corrosion products were formed on samples exposed to atmospheres with high concentration of H 2 S which agreed with the corrosion rate determined by mass loss and electrochemical chronopotentiometry (cathodic reduction). The electrochemical noise methodology proposed in this work showed acceptable and reproducible results by using an electrochemical cell in which the electrolyte was formed by a distilledwater wetted cloth in contact with the compounds present on a corroded metallic surface. This methodology indicated that the corrosion protection level of the corrosion products formed on copper is related to the corrosivity of the atmosphere.