Brown spots on Aluminium circles developed during storage

The control of corrosion and staining of metals and alloys during storage and transit is very important from the point of view of manufacturers and users. An interesting case of the development of brown spots on aluminium circles during storage was investigated. The paper describes various experiments carried out to establish condensed moisture at confined spaces formed between stacked circles. The presence of moisture was due to the daily fluctuation in the relative humidity and the temperature of the storage room. Various preventive measures for such type of corrosion are discussed.