Although steel is a durable metal, you still need to apply protective finishes to make it stand the test of time.
Read on to learn about the different types of protective steel finishes.
In construction it is still the case that steel is the most popular material used in projects.
It’s no coincidence that apart from the exotic & expensive alloys it is also the strongest. Easy to manipulate, cost effective and hard wearing. Despite all these benefits most steel used in construction will have an additional surface layer finished onto it.
This surface finish can be used as a design element to make it more easy on they eye, but its primary use is protection. Helping to extend the steels lifespan into the long term.
Some times this surface layer can even used to compound and improve existing properties within the steel.
The job of these surface layers and finishes is to protect the material from harsh atmosphere and conditions. Particularly when used outside.
In any case though its important to consider the different coatings and finishes when purchasing steel.
1. Epoxy Coating
Used primarily for industrial applications. Epoxy can be considered a ‘two part’ finish whereby it used both coating and primer. It is designed to protect the steel material from corrosion and oxidation.The ‘catch and release’ system works similar to the process seen in VCI Poly Bags.
The epoxy is hard wearing and will protect against friction, acids & alkalies as well as moisture damage and gasoline products.
2. Hot Dip Galvanising
When steel is exposed to UV rays or is placed near salt water, Hot Dip is the best protective finish you can get.
During the process the steel is dipped in hot zinc. This forms a durable & thick layer that provides VCI corrosion protection into the long term. The zinc here acts as a sacrificial anode which corrodes itself rather than the steel it is protecting.
3. Powder Coating
This protective finish utilised a powder formula paint manufactured form bespoke resins and pigments. The dry powder are charged electrostatically in order to attract paint particles towards the surface area of the steel. This kind of coating is cost effective and affordable for most projects. It can be applied using different colours and is often used in projects where design and aesthetic value are key drivers.
4. Metal Plating
This uses a chemical bath in order to impart a thin layer of metal or PTFE/Nickel on to the steel. This is an effective process for export packaging improving the metals durability and corrosion resistance. Metal Plating as a surface coating for aesthetics however is not ideal. Often there will be surface defects on the steel itself which cannot be smoothed out.
5. Apply Oil
Applying oil to steel is a practical method for extending its lifespan. Oil acts as a lubricant, reducing friction and forming a protective shield against rust by preventing moisture from interacting with the metal.
While this approach is effective, it has drawbacks, including reduced grip, potential for slippage, messiness, and the need for regular reapplication, making it a trade-off between rust prevention and practicality.
6. Store properly
To ensure steel longevity, proper storage is paramount. Rust prevention hinges on minimising moisture contact, as water triggers rust formation in iron. While eliminating all moisture with an airtight seal is ideal, it's often impractical. Humidity in the air is a constant challenge.
Therefore, the most sensible approach is to focus on rust prevention during storage and shipping, safeguarding steel from corrosion in the real world where complete moisture isolation is unfeasible.
7. Blue-ing
Blueing is an effective method for enhancing steel's durability. This process forms a protective layer of magnetite, resembling rust but less harmful. Achieved through heat and salt treatment, it imparts a black or blue-black hue to metal surfaces. Often employed to shield firearms economically from rust, blueing is most effective when combined with regular oiling. This double protection extends steel's lifespan while enhancing its aesthetic appeal.
8. Use VCI Packaging
VCI Packaging, short for Vapor Corrosion Inhibitor Packaging, is a simple and dry way to stop metal and metal parts from getting rusty. It uses special chemicals to protect different types of metals from getting damaged. These chemicals are put into materials like plastic, paper, and others that are used for packaging.
When you keep metal parts in VCI Packaging, these special chemicals start working and make a shield on the metal's surface. This shield pushes away moisture and stops rust from happening. It's better than using messy oils, greases, or coatings, and it doesn't take a lot of time. This helps metal last longer and makes it easier to take care of.
9. Cathode Protection
Cathodic protection is a leading method to prevent rust on metal surfaces. It combats corrosion by designating the metal as the cathode in an electrochemical cell. This simple and highly effective technique is widely used to safeguard fuel pipelines, steel water storage tanks, water heaters, boat hulls, and more. By making the metal a cathode, cathodic protection significantly extends the lifespan of steel and other metallic structures, ensuring their longevity in various applications.
10. Avoid cracks
Preventing rust on metal begins with addressing cracks and scratches. These vulnerabilities expose the metal to deeper water infiltration. Using cold-rolled steel, rather than hot-rolled, is a solution. Cold-rolled steel offers a smoother surface without the texture that traps moisture, reducing the risk of rust. Protecting metal from scratches and cracks is a vital step in ensuring its longevity.
Preventing rust on metal begins with addressing cracks and scratches. These vulnerabilities expose the metal to deeper water infiltration. Using cold-rolled steel, rather than hot-rolled, is a solution. Cold-rolled steel offers a smoother surface without the texture that traps moisture, reducing the risk of rust. Protecting metal from scratches and cracks is a vital step in ensuring its longevity.
