What type of corrosion is carbon steel most susceptible to?

Carbon steel is most susceptible to pitting corrosion, which is a localized form of corrosion that leads to the creation of small holes or "pits" in the material. This type of corrosion occurs when the protective oxide layer on the steel is broken down, often due to environmental factors like moisture, chlorides, and low oxygen levels that promote localized electrolyte conditions.

In the case of carbon steel, when exposed to corrosive environments, pitting can happen rapidly and is often difficult to detect without careful inspection, as it does not affect the entirety of the material's surface. The formation of pits can compromise the structural integrity of components over time, making this type of corrosion particularly concerning for applications in marine, chemical, and other harsh environments.

Other types of corrosion listed may affect various materials and conditions, but pitting corrosion is the most concrete risk for carbon steel specifically, under typical exposure scenarios where localized attack occurs. This understanding is essential for those involved in maintenance and material selection in environments where carbon steel is used.