Crevice corrosion is a localized form of corrosion attack.
Generally, metallic corrosion involves the degradation of an exposed metal surface. Corrosion occurs in various forms ranging from uniform attacks over the entire surface to severe local attacks.
Crevice corrosion starts more easily than for example pitting corrosion, another form of localized corrosion. Crevice corrosion occurs at narrow openings or spaces between two metal surfaces or between metals and non-metal surfaces. It is usually associated with stagnant conditions in the crevice. Crevices, such as those found at flange joints or at threaded connections, are thus often the most susceptible to corrosion attacks.