Pitting corrosion is a form of localized corrosion, leading to the formation of small holes or pits in a metal surface. It can penetrate quickly and deeply, inflicting considerable structural damage even when the metal surface appears to be unaffected.

Key Features:

• Highly localized damage: Pitting attacks specific areas and is therefore more difficult to detect and more hazardous than uniform corrosion.
• Caused by chlorides: Pitting corrosion occurs when chloride ions are present (e.g., in seawater or salty atmospheres). Commonly affected metals include stainless steel and aluminum.
• Difficult to identify: Pitting can start as a microscopic defect but grow internally; as a result, the metal can be weakened significantly while the surface looks mostly intact.

Pitting corrosion is a significant risk in industries utilizing metals exposed to moisture, chemicals, or marine environments. It can compromise pipelines, tanks, aircraft components, and appliances. Regular inspection, protective coatings or isolation, and the use of non-corrosive alloys are all ways to protect against pitting. Pitting forms stress concentrators in metals, which can lead to sudden failures, thereby making it imperative to study and manage this form of corrosion for safety, durability, and performance in engineering applications.