Atmospheric corrosion in the Canary Islands (Spain). Part II: Zinc

Abstract

This article presents results on the study of atmospheric corrosion of zinc in the Las Palmas province (Canary Island, Spain). Very high rates of corrosion were observed, in many cases exceeding the C5 limit specified by international norm ISO 9223. Chloride ion is found as the main causing factor for these high rates of corrosion, together with the high values of relative humidity. In analysis of corrosion products, the most common is simonkolleite. Data on velocity have been treated using various models. The bilogarithmic law gives a good fit in 86% of the cases analyzed (r2 >0.9). It was concluded that on Grand Canary Island the highest corrosion levels were located at stations near the coastline due to the high levels of chlorides and sulfates occurring in marine breezes.