Cathodic and Anodic Protection

Abstract

As Volta already observed in early 1800s, a current that is exchanged between a metal surface and the electrolyte to which it is exposed modifies the behaviour of the metal, increasing the corrosion rate or reducing it. Some years later, Davy put in practice such concept demonstrating the possible implications, which, after about a dormant century, started to have effective industrial use: with Davy, cathodic protection was born. A century and a half from Volta’s observations, Edeleanu showed that Hickling potentiostat could control corrosion by making an anodic polarization and Riggs made the first commercial application of anodic protection: hence, anodic protection was also born. Both techniques are set up by establishing a cathodic or anodic current