4 Types of Protective Finishes for Steel


Steel remains the most common material used for construction projects and machines nowadays. That’s because it is one of the strongest materials available. It is also easy to manipulate, cost-efficient, and incredibly durable. Even with all these benefits, most types of steel have a surface finish added to complement their intended use.

In cases where the appearance of steel is an essential element, the surface finish is specified as a design element. In non-decorative cases, the surface finish might be protective or meant to confer different properties on the steel.

When considering buying steel online, the most common non-decorative finish you will get is a protective finish. Though generally classified as protective, the finishes also have aesthetic benefits for your products. They are the first line of defense against harsh weather elements, condensation, and open exposure.

Here are the common types of protective steel finishes:

1. Epoxy Coating

This is among the best options for industrial applications. The epoxy is also called a two-part finish since it comprises a finish coat and a primer. It is designed for the protection of steel substrates from corrosion and oxidation. The epoxy coating is extremely hard and resistant to friction, alkali, acids, condensation, and petroleum products. It protects the underlying steel from temperature variations, impact forces, particle abrasion, and turbulence. Epoxy-coated steel is generally used for products meant for power plants, machinery, construction, pump and manufacturing applications, and gas and oil pipelines.

2. Hot Dip Galvanizing

This is the best protective finish for steel products that will be exposed to UV rays or those installed near salt water. In the hot dip galvanizing process, steel is dipped into hot zinc, which forms a durable and thick layer on its surface to protect it from corrosion. The zinc acts as the sacrificial anode in most applications and corrodes rather than the underlying metal.

Hot dip galvanized steel products are recyclable and resistant to abrasion, impact, temperature, and turbulence. This is the primary protective coating used for marine, water treatment, solar, paper mill, and offshore manufacturing applications.

3. Powder Coating

Different steel barsThis protective finish involves the application of powdered paint made of specialized resins, filers, and pigments. The dry powder particles are charged electrostatically to attract paint particles onto the surface of the steel where the charge also holds them in place during curing under high temperatures. Powder coating is inexpensive and offers an impact-resistant surface. Moreover, it exists in different colors and is used for applications in which aesthetics is valued.

4. Metal Plating

This involves the coating of steel under a chemical bath with a thin metal layer of PTFE or nickel. The process improves the steel’s durability, surface friction, appearance, and corrosion resistance. However, metal plating will not smooth out surface defects on the steel.

When shopping online, you might not readily decipher the above coatings on your steel products. In fact, it is also difficult for a novice to recognize the coatings when evaluating a product in person. You can only be sure that they are effectively applied and they offer the highest type of protection for your products if you deal with a reputable supplier.

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