Most of us has been affected by corrosion our boats.
There are different types of corrosion affecting our boats:
In simple words, Corrosion is the irreversible damage or destruction of a material due to a chemical or electrochemical reaction with the environment.
Metal Corrosion is Caused when it reacts with another substance such as oxygen, hydrogen, an electrical current, or even dirt and bacteria. Corrosion can also happen when metals like steel are placed under too much stress causing the material to crack
On boats are mainly three types of corrosion:
Galvanic Corrosion:
It is simply an electrochemical reaction between two or more different metals. The metals must be different because one must be more chemically active (or less stable) than the others for a reaction to take place. When we talk about galvanic corrosion, we’re talking about the electrical exchange. All metals have electrical potential because all atoms have electrons, which have an electrochemical charge. (see https://www.boatus.com/)

Electrolytic Corrosion:
It is simply a process of accelerated corrosion. In this process, a metallic surface is continuously corroded by other metal it is in contact with, due to an electrolyte and the flow of an electrical current between the two metals, caused from an external source of electromotive force.

Ordinary Corrosion:
Some times called rust, it is a chemical process which results in the formation of red or orange coating on the surface of metals, this reaction causes damage and disintegration of the metal starting from the portion of the metal exposed to the environment and spreading to the entire bulk of the metal.
