Zinc anodes

Anodes for propeller shaft and engine

In the marine environment, galvanic corrosion occurs. This is an electrochemical process caused by the difference in potential between two dissimilar metals in an electrolyte. Salt water acts as such an electrolyte, and the boat and its components submerged in water form a kind of galvanic cell. Due to the difference in potential between metals in the electrolyte, there is a continuous flow of ions from the less noble metal / metal with lower potential (e.g. steel, zinc, magnesium), which becomes the anode, to the more noble metal / metal with higher potential (e.g. bronze, copper), which acts as the cathode. This flow of ions causes material loss in the metal with the lower potential, for example the hull.

Zinc anodes are used to protect boat components submerged in seawater from corrosion. The absence of material loss on the anode is a sign of incorrect anode installation. The anode must not be painted.