Atmospheric Corrosion

Abstract

Atmospheric corrosion is the most prevalent type of corrosion for zinc, owing to extensive outdoor applications of galvanized steels. Numerous research programs have been carried out in the past to investigate the corrosion behavior of zinc in various types of atmosphere. The testing methods used in these investigations can be generally divided into two groups: field exposure testing and simulated testing. Data from field exposure represent a real corrosion rate in an atmospheric environment, while those from simulated testing provide specific information on the effects of the atmospheric variables. In view of this intrinsic difference, information from real field exposure testing and that from simulated testing are presented separately in this chapter. A brief description is provided first on the atmospheric factors involved in a corrosion process. The mechanisms for atmospheric corrosion of zinc are discussed at the end of the chapter.