How Corrosion Spreads in Metals

corrosion of metals

Iron oxide or what it is commonly called as rust is a form of corrosion created by the reaction of iron (or any of its alloys) and oxygen, with the presence of water or air moisture. But how does it work and spread?

There are other metals that do have an oxidation process but work differently. They form results that are not commonly considered rust. Aluminium corrosion spreads very slow while copper corrosion can be identified by its green colour.

Molecular process of corrosion of metals

How does corrosion spread in metals?

Metal corrosion is an electrochemical process that happens on a molecular level. It occurs when an electron transfers from an iron molecule to surrounding oxygen molecules. This is what changes the makeup of the iron, turning it into rust.

Such a process happens to iron all the time, given that affecting factors are always present. A proof to this is that it is impossible not to see some oxide present within a piece of iron. It is a fact that rust rate is usually slow but is accelerated due to water, especially if the water is highly concentrated with electrolytes or substances in the water that make it easier for electrons to move. A perfect example of this is salt. The presence of salt in a solution can cause rust to spread in metals more quickly.

How rust spreads

Unlike a biological infection, the process of iron oxidisation or rust occurs independently on the condition of a piece of metal’s surrounding. This only means that if one part of the metal is exposed to electrolytes, oxygen, or water, it is prone to rusting. Even the portion of the metal that was kept clean and dry will not rest due to the rate of the exposed part.

Iron alloys have dissimilar corrosion rates as influenced by their respective structure.

Ways to prevent rust

Peelable Protective Coatings are becoming more and more popular due to their ease of use and rust-inhibiting factors.

But none of them actually completely prevent rust forming on the service.

Except Unituff Coatings.

If you want to learn more about how corrosion of metals work, contact us at, or +61 400 796 022 or +1 832-533-5628 or