Cathodic corrosion protection

Cathodic corrosion protection is a proven technique used in various industries to protect metallic structures from the damaging effects of corrosion. In this process, an external current is applied to the metal surface to be protected, turning it into the cathode of an electrochemical cell. This process reduces or even completely stops the speed of the corrosion reaction.

The basis of cathodic corrosion protection is based on the principles of electrochemical corrosion. Metals in contact with an electrolyte can undergo an electrochemical reaction in which they release electrons and are converted into dissolved ions. This flow of electrons from the metal structure to other materials or the environment is the actual process of corrosion. By applying an external current, the cathodic reaction, in which electrons are transferred to the metal surface, is intensified, resulting in the metal surface being protected against corrosion.

There are two main methods of cathodic corrosion protection: electroplating and impressed current cathodic protection (ICCP). In galvanization, a sacrificial anode made of a less noble metal, such as zinc, is connected to the metal to be protected. The zinc releases electrons and sacrifices itself, so to speak, in order to enable the cathodic reaction and preserve the metal to be protected. ICCP, on the other hand, uses an external circuit emitted by a current source to deliver the necessary electrons to the cathode and prevent corrosion.

Cathodic protection is used in a variety of applications, including pipelines, ship hulls, bridges, tanks and other metallic structures exposed to environmental corrosion. By using this technique, the service life of metal structures can be extended, maintenance costs reduced and reliability and safety increased.