This article provides an overview of the metallurgical effects on corrosion of different series of aluminum alloys (1xxx, 2xxx, 3xxx, 4xxx, 5xxx, 6xxx, and 7xxx) that are classified into two categories. The first category includes the effects from insoluble, intermetallic constituent particles generally formed from trace impurity elements that play a predominant role in pitting corrosion. The second category comprises the effects from precipitation of secondary phases and effects from solute remaining in solid solution on corrosion of aluminum.
This article addresses the general effects of the composition, mechanical treatment, surface treatment, and processing on the corrosion resistance of aluminum and aluminum alloys. There are five major alloying elements: copper, manganese, silicon, magnesium, and zinc, which significantly influence the properties of aluminum alloys. There are organic coatings or paints that provide a barrier between a corrosive environment and aluminum surface. Inorganic coatings, including claddings, and enhanced oxides, such as anodized films, Boehmite films, and conversion coatings also help in corrosion prevention. The article assists in the information on selection of fabrication operations, as they play an important role in corrosion resistance.