galvanic corrosion
Galvanic corrosion is the most common electrochemical corrosion between the two dissimilar metals that maintained electrical contact in the presence of an electrolyte. This leads to the preferred and faster corrosion of the less noble metal. 

Key Features:

  • Causes and Mechanism: When shaped metals with different electrochemical potentials circuit through an electrolyte, like water, saltwater or humidity. The most active or anodic metal is the one that will corrode faster, while the more noble or cathodic one is that protected.
  • Commonly Affected Materials:  Common with structures of either aluminum and steel, copper and iron, or zinc and stainless steel in contact. Affect marine equipment, pipelines, fasteners, and automotive parts.
  • Prevention Methods: Distancing the dissimilar metals with insulation.  Using protective coatings like paints or galvanization. Selection of metals that are closer in galvanic series, so as to minimize potential difference. Sacrificial anodes such as zinc anodes in ship hulls are used to direct possible corrosion away from the crucial component. 

Galvanic corrosion is of concern in engineering, construction, and marine industries. It requires the appropriate selection of materials and protection strategies for durability and longevity of metal components.