Corrosion is arguably the most vast and complex form of wear and a science on its own. Since it is usually a surface attack, the surface can be protected to stop or reduce corrosion. Almost all corrosion is the result of some form of chemical, electro-chemical attack, or oxidation. In the case of steel, rust can form, which is a powder when dry that can easily be removed from the surface of a component.
The severity of corrosion is predominantly determined by the conditions under which it occurs, such as type of corrosive material, concentration, pH, temperature and more. A small variance in any of the aforementioned parameters can result in vast changes in the corrosion rate and severity thereof. Very thin surface coatings are used, such as paints and galvanized layers, which makes thermal spray and non-metallic materials ideal for such applications.