katodisuojausmenetelmiä

katodisuojausm is a Finnish term that translates to cathodic protection. It is a technique used to prevent or slow down the corrosion of a metal surface by making it the cathode of an electrochemical cell. This is achieved by connecting the metal to be protected to a more easily corroded "sacrificial anode" or by using an external power source to supply electrons to the metal.

In cathodic protection, the metal undergoing corrosion would normally lose electrons as it oxidizes. By making it the cathode, it receives electrons, thus preventing or reducing its oxidation and subsequent corrosion. This is particularly important for underground pipelines, ship hulls, offshore structures, and other metal components exposed to corrosive environments like soil, saltwater, or even the atmosphere.

There are two main types of cathodic protection: sacrificial anode cathodic protection and impressed current cathodic protection. Sacrificial anode systems use a metal that is more electrochemically active than the metal being protected. This sacrificial anode corrodes instead of the protected structure. Impressed current systems, on the other hand, use an external DC power source to drive current from an inert anode to the structure, effectively making it cathodic. The choice between these methods depends on factors such as the size of the structure, the corrosivity of the environment, and the desired lifespan of the protection.