The modern world is built on steel. Vehicles, office blocks, factories, railways and most infrastructure has steel at its core, but despite its popularity steel has a major vulnerability - corrosion.
Left on its own, steel will rust into a pile of browny red flakes. The most practical way around this to apply surface protection and in this article, we will discuss the different types of surface protection and their lifecycles.
But first, let’s look more into why steel corrodes over time.
Why Does Steel Need Surface Protection?
The formation of rust is corrosive process caused by electrons in oxygen and water being attracted to the iron in steel. Iron is the main component in the composition of steel and so there is a high rate of attraction of these electrons from the environment around the steel.
It is well known that salt increases steel’s vulnerability to corrosion. The reason for this is because salt is an electrolyte and magnifies the pull of electrons onto the surface of iron-based metals.
How to Prevent Rust
- Keep it dry!
Without having to attract moisture out of the air around it, steel will rust much faster because the electrons are already on its surface.
- Keep it clean!
Dirt contains moisture and pollutants that act as catalysts for rust in the same way that salt does. Keep the surface of the steel as well as the area around it as clean as possible.
- Apply surface protection
By far the most effective, surface protection is the hassle-free way to go to prevent corrosion for the long term.
Types of Surface Protection
For medium to long-term protection, many high-performance paint systems are available. Depending on quality and environment factors these systems can protect for between 5 and 20 years.
Hot Dipped Galvanizing
If you need your steel product to last more than 20 years it needs to be hot dip galvanized. The steel item is dipped into a bath of molten Zinc that is heated to 450 degrees Celsius. At that temperature, the Zinc and the Iron in the steel react to form an alloy (combination) and as the item is removed from the bath a layer of pure Zinc is deposited onto the surface creating a barrier between the iron and the elements that cause it to corrode.