Abstract
Nine test sites were established in the Eastern coast (Gulf Sea) and Western coast (Red Sea) of Saudi Arabia. In each environment, sulphur dioxide and chloride deposition rates were measured and the corrosion rates of rectangular samples (aluminium) were determined. In two typical test stations (a marine and a marine-industrial), the time of wetness was registered, then the influence on metallic corrosion rates discussed. The obtained data were used for classification of atmospheric aggressivity, according to ISO 9223. It was observed that the aggressivity categories of marine zones are C2, C2, C4 and C5 (the highest one), whereas the marine-industrial sites classify as C3, C2, C4, C3 and C3. Corrosion products and contaminants have been analysed by X-ray diffraction. By using the equation C = At
n
, where C is corrosion rate after t years, A is corrosion rate after the first year of exposition, and n is constant, based on n values, the corrosion rate values of aluminium samples are predicted.