Cathodic Protection

Corrosion & Protection

Определение

An electrochemical technique that prevents corrosion of a metal structure by making it the cathode of an electrochemical cell, either by connecting it to a sacrificial anode or by applying an impressed direct current.

Подробное объяснение

Sacrificial anode cathodic protection uses metals more active than the structure (typically zinc, aluminum, or magnesium anodes) that corrode preferentially, protecting steel ship hulls, offshore platforms, and buried pipelines. Impressed current cathodic protection (ICCP) uses an external DC power supply to force the protected structure to a sufficiently negative potential. The degree of protection can be monitored by measuring the structure-to-electrolyte potential, with steel typically requiring a potential of at least −850 mV vs. Cu/CuSO₄ electrode.