Galvanised Steel: Benefits, Uses, and How It’s Made

Galvanised steel is one of the most widely used materials in modern manufacturing due to its durability, cost effectiveness and the zinc coating that prevents rust. 

What is Galvanised Steel?

Galvanised steel is steel that has been coated in a thin layer of zinc to protect it from rust and corrosion. The zinc coating acts as a barrier to the environment so increases the metal’s durability and strength compared to metals that rust. This, alongside the versatility, makes it popular for a variety of projects and industries. 

How is it different from other types of steel? 

Galvanised steel is specifically designed to combat rust. When thinking about mild steel vs stainless steel, there are a few key differences. Mild steel is prone to corrosion when exposed to moisture unless it is painted or treated. Stainless steel naturally resists corrosion as it contains chromium, however this does make it more expensive. Ideal for outdoor use and a cost-effective alternative, galvanised steel is a great option for outdoor use. 

Key Benefits of Galvanised Steel

Galvanised steel benefits include exceptional durability, corrosion resistance, and long-term cost savings. They are widely recognised across many industries. 

Corrosion Resistance

The addition of a protective zinc coating makes galvanised steel highly resistant to corrosion, even in harsh and challenging environments. The zinc layer acts as a physical barrier and also offers sacrificial protection, meaning it corrodes in place of the steel underneath. This protection extends into hard-to-reach areas such as sharp corners, edges, and recessed surfaces that other coatings may not adequately cover, ensuring uniform corrosion resistance throughout the entire component.

Durability

Galvanised steel is known for its long-lasting performance. In average conditions, a zinc-coated steel product can last more than 50 years without significant breakdown. Even in more aggressive environments with high moisture or water exposure, such as coastal or industrial areas, it can provide effective protection for over 20 years without requiring maintenance. This longevity makes it a reliable choice for infrastructure, construction, and outdoor applications.

Cost-effective

Although the initial cost of galvanising may be higher than some other protective methods, its long service life and lack of maintenance needs result in significant savings over time. By reducing the need for repairs, replacements, or touch-ups, galvanised steel proves to be a cost-effective solution for both short-term projects and long-term investments.

Ready to Use

Galvanised steel arrives from the supplier fully coated and protected, requiring no further surface treatment, painting, or preparation before installation. This reduces lead times and labour costs on-site, making it ideal for projects with tight schedules or limited resources. Its ready-to-use nature simplifies logistics and speeds up construction timelines.

Environmentally Friendly

Galvanised steel is a sustainable material choice. The galvanising process does not produce significant waste. At the end of its life, galvanised steel can be recovered and reused without loss of quality, contributing to circular economy practices and reducing the environmental footprint of construction and manufacturing projects.

How is Galvanised Steel Made?

There are a few methods of galvanisation: 

1. Hot Dip Galvanising

The steel is dipped into zinc that is around 460 degrees which forms a metallurgical bond that results in a firm layer of pure zinc. Once the metal is pulled out of the molten zinc, the pure zinc mixes with the oxygen in the atmosphere to form zinc oxide. The zinc oxide then reacts with the carbon dioxide and forms zinc carbonate which completes the final protective coating. This is a cost-effective method that can be quickly done and on complex shapes too. 

2. Pre-galvanising 

This method is performed at the very first stage of production. It involves rolling sheet metal through a cleaning agent to prime the material for galvanising. The metal is then passed through molten zinc and immediately recoiled. The benefit of this method is that coils of steel can be quickly galvanised on a larger scale with a more unified coating as opposed to the hot-dip method. 

3. Electrogalvanising

This method doesn’t involve any molten zinc. Instead, an electric current is used to reduce positively charged zinc ions to zinc metal which is then deposited on the positively charged steel. The main benefit of this technique is that it creates an even coating on the steel. However, the coating is thinner than when the hot dip method is used and has a shorter lifespan. 

Common Uses of Galvanised Steel

Galvanised steel uses are found in a wide range of industries. Wherever there is a risk of corrosion, galvanised steel should be used.

• Construction – Galvanised steel is widely used in the construction industry and commonly found in beams, columns, and frameworks, where long-term reliability is essential. Its ability to withstand exposure to the elements with minimal maintenance makes it a preferred choice for both residential and commercial buildings, as well as infrastructure projects like bridges and walkways.
• Automotive – Galvanised steel is often used in the manufacturing of cars, trucks, and other vehicles for body panels, chassis parts, and undercarriage components to provide resistance against rust and extend vehicle life. The combination of strength and corrosion protection helps improve safety, reduce repair costs, and maintain vehicle appearance over time.
• Agriculture – This material is a staple in agricultural applications due to its ability to endure rough conditions, including exposure to moisture, chemicals, and outdoor weather. It is used in the construction of farm equipment, machinery frames, irrigation systems, fencing, livestock enclosures, feeders, and grain silos. Its long-lasting nature reduces the need for constant replacements, making it a practical and economical solution for farmers.
• Marine – The marine industry requires materials that can perform reliably in wet, salty, and corrosive environments, and galvanised steel is well-suited for this role. It is used in boat trailers, docks, offshore platforms, ladders, and other structural or support components exposed to seawater or humid coastal air. The zinc coating offers a strong defence against saltwater corrosion, which significantly prolongs the service life of components in marine and coastal applications.
• Industrial Fabrication – from appliances and electronics to machinery and equipment, galvanised steel is used in many manufacturing processes. This includes appliances, electrical enclosures and heavy machinery. Its ease of fabrication, combined with corrosion resistance and mechanical strength, makes it a versatile and dependable material in industrial design, assembly, and production processes.

Services at Salamander Fabrications 

At Salamander, we’ve been working with all kinds of sheet metal fabrication technologies since 1968. We offer services such as, welding and laser cutting to companies all over the UK, and work with a huge range of sectors to provide them with quality products, quickly, efficiently and with excellent customer service every step of the way.