ABSTRACT
This chapter examines the issues concerning what is corrosion and why does aluminum corrode. Corrosion is the chemical reaction of a metal, in this case aluminum, with its environment, which leads to the deterioration of the properties of the aluminum. Aluminum is a very reactive metal, but it is also a passive metal. This contradictory nature is explainable because nascent aluminum reacts with oxygen or water and forms a coherent surface oxide which impedes further reaction of aluminum with the environment (Fig. 1). Aluminum is chemically very reactive. For example, powdered aluminum is used as rocket propellant for propulsion of the space shuttle’s solid fuel rockets. Additionally, the reaction of aluminum with water releases a tremendous amount of energy: () Al + 3 H 2 O → Al ( OH ) 3 + 3 H 2 ↑ Δ G= − 1 .1 MJ mol https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429223259/a9a44f48-abbd-4f84-9837-bef5a3a56592/content/eq387.tif"/> Aluminum is passivated in air by a thin film of aluminum oxide. https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780429223259/a9a44f48-abbd-4f84-9837-bef5a3a56592/content/fig11_1.tif"/>
