Cathodic protection using MMO-coated titanium anodes

The current generated in the potentiostat flows to the structure via an MMO-coated titanium anode, causing cathodic polarization. As a result, corrosion processes are virtually eliminated. Cathodic polarization of the protected object also causes local changes in pH around it, leading to the precipitation of poorly soluble compounds that seal any discontinuities in the protective coating (e.g., enamel). This provides additional insulation of the steel structure from the corrosive environment.

Titanium anodes are characterized by stability and long service life. They are practically not consumed during the cathodic protection process, as oxygen is released on their surface. In practice, these anodes can operate for over 10 years, whereas the expected lifespan of a magnesium anode is about 2 years.

The most commonly used in cathodic protection, especially in drinking water tanks, are titanium anodes coated with an MMO (mixed metal oxide) layer containing iridium and tantalum oxides.

MMO-coated titanium anodes are used in various environments, including seawater, brackish water, freshwater, carbon backfill, and concrete.