elektrokorrosive

Elektrokorrosive, or electrocorrosion, is metal loss caused by electrochemical reactions driven by electrical potential differences. It includes corrosion from stray currents, galvanic coupling of dissimilar metals, or external currents in an electrolyte. The term is used in several languages to describe corrosion that is accelerated by electrical energy rather than chemistry alone.

Mechanism: Anodic metal dissolution occurs where oxidation takes place, while cathodic reduction reactions occur elsewhere. An external circuit or potential difference drives electrons through the metal and ions through the surrounding electrolyte, forming corrosion cells. The rate depends on the metal, surface condition, electrolyte conductivity, temperature, and current magnitude.

Contexts and consequences: Buried or submerged structures are prone to electrocorrosion from stray currents in grounding networks or nearby power lines. Dissimilar metals in contact can form galvanic cells, accelerating loss at the anodic side. Resulting damage includes leaks, reduced strength, and service disruptions.

Common forms: galvanic corrosion between dissimilar metals, stray-current corrosion from electrical networks, and electrolytic corrosion from imposed currents. Localized forms such as pitting or crevice corrosion may accompany electrocorrosion.

Prevention and mitigation: select compatible materials, apply protective coatings, and minimize exposure to electrolytes. Use cathodic protection (sacrificial anodes or impressed current) and proper insulation to reduce potential differences. Regular monitoring of potentials and currents helps detect problems early.

See also: corrosion, galvanic corrosion, cathodic protection.