Sacrificial Anode Contractors

As in the above two images, the first image says the iron materials are protected from corrosion because of using the Sacrificial Anode. If a Sacrificial Anode is not used, the material rusts and gets damaged due to corrosion, as shown in the second image.

The principle of cathodic protection is in connecting an external anode to the material to be protected from corrosion and the passing of an electrical DC current. So that all areas of the metal surface become cathodic and therefore do not corrode. The external anode may be a galvanic (sacrificial) anode or it may be an impressed current anode where the current is impressed from an external D.C. source. Three metals that can be used as sacrificial anodes are zinc, aluminium, and magnesium.

Sacrificial Anodes are highly active metals that are used to prevent a less active material surface from corroding. They are created from a metal alloy with a more negative electrochemical potential than the other metal it will be used to protect. The sacrificial anode will be consumed in place of the metal it is protecting, which is why it is referred to as a “sacrificial” anode.

Sacrificial Anodes are used in concrete, to prevent further corrosion in reinforcement. Anodes are surrounded by Alkali activated mortar, once installed or fastened to the reinforcement steel, zinc core sacrifices itself and protects the reinforcement steel.

The materials used for sacrificial anodes are either relatively pure active metals, such as zinc or magnesium, or are magnesium or aluminum alloys that have been specifically developed for use as sacrificial anodes. In applications, where the anodes are buried, a special backfill material surrounds the anode in order to ensure that the anode will produce the desired output.