Localized chemical or mechanical damage to the protective oxide film; water chemistry factors which can cause breakdown of a passive film are acidity, low dissolved oxygen concentrations.
Corrosion of a metal surface, confined to a point or small area, that takes the form of cavities.
Ratio of the depth of the deepest pit resulting from corrosion divided by the average penetration as calculated from weight loss.
An empirical relationship to predict the pitting resistance of austenitic and duplex stainless steels.
What is galvanic corrosion?
Galvanic corrosion (also called ' dissimilar metal corrosion' or wrongly 'electrolysis') refers to corrosion damage induced when two dissimilar materials are coupled in a corrosive electrolyte.
A localized form of corrosion usually associated with a stagnant solution on the micro-environmental level.
An acceleration in the rate of corrosion attack in metal due to the relative motion of a corrosive fluid and a metal surface.
Corrosion damage induced under load and in the presence of repeated relative surface motion.
What is pack rust?
Pack rust is often used in relation to bridge inspection to describe built-up members of steel bridges which are already showing signs of rust packing between steel plates.
Powdered rust particles relatively dense that are commonly used as additives to asphalt to improve the anti sliding properties of the pavement.
Pack rust is a form a corrosion typical of steel components that develop a crevice into an open atmospheric environment.
Rust settling as crud in boilers and other devices where the evaporation of water combined with normal corrosion of vessels leads to such accumulation of debris.
What is dealloying?
Dealloying is the selective leaching of one element from an alloy by corrosion processes.
Dezincification of unstabilized brass, whereby a weakened, porous copper structure is produced.
Corrosion attack usually related to the segregation of specific elements or the formation of a compound in the grain boundary regions.
Graphitic corrosion of the porous graphite network when a gray cast iron is impregnated with insoluble corrosion products.
What can cause stress corrosion cells?
General thinning.
Regions within a metal subject to a high local stress.
