Things you must know about Galvanized Sheet Metal

The process of galvanizing was first introduced by Sorel in 1836 in France. This is accomplished by dipping the metal in molten zinc after initial cleaning. In 1844, just seven years after William Crawford’s invention, the British Royal Navy began employing galvanized steel to construct ships at the Pembroke Docks in Whales. By 1850, 10,000 tons of zinc were being used annually by British steelmakers to prevent corrosion on iron.

What is Galvanization?

Metal parts can be protected from corrosion using the tried-and-true, affordable, and long-lasting technique of galvanization. In essence, it is a surface treatment to coat metal surfaces by immersing the metals into a molten zinc metal bath. The zinc coating aids in the protection of base metal against corrosion.

The coated metal product provides excellent quality and extends product life. Many manufacturers suggest using a galvanized coating on sheet metal because it offers the best protection against corrosive elements. Due to its superior strength, low maintenance cost and wide range of applications, it becomes the top choice in the market.

How galvanization protects the metal?

Galvanization is one of the most often-used methods of preventing corrosion among the many existing techniques. Sign boards, automotive parts, and numerous items are made of galvanized metal. This is because metals are susceptible to corrosion; thus, galvanization offers the required corrosion protection by:

  • Creating a protective layer that separates the base metal structure from the environment i.e. wind, humidity, and ice.
  • The electrochemical properties of zinc help the base metal to corrode at a slower pace than copper and other elements.

Let’s go through the four different ways that manufacturers galvanize their metals.

Types of galvanized sheet metal

There are different types of galvanized sheet metal and these are listed below:

  • Hot-dipped galvanized steel
  • Electro-plated galvanized steel
  • Galvannealing
  • Pre-galvanizing

Hot-dipped galvanized steel

  • Hot-dip galvanizing is the first method of galvanization. This process involves dipping steel or iron into a pool of zinc that maintains a temperature of around 850°F (450°C).
  • The metallurgical connection between the zinc and the receiving metal is formed during this process.
  • Pure zinc reacts with oxygen to generate zinc oxide once the metal has been removed from the solution.
  • The last layer of protection on the material is created by the zinc oxide’s subsequent reaction with carbon dioxide to produce zinc carbonate.

The liquid hot-dipped galvanizing technique is a rapid and affordable option for simple materials and complex geometries. Galvanized sheet metal can be utilized in high-temperature applications up to 392°F.

Electro-plated galvanized steel

Steel that has been electro-galvanized is another name for electro-plated sheet metal.

  • In this method, electrolytic deposition is used to place a thin layer of zinc on the surface of sheet metal, similar to how powder coating is done.
  • It is often better for steel components that won’t face severe exposure outdoors since it doesn’t produce a layer of zinc that is as thick as the hot-dipping method formulates.


  • The method of “galvannealing” which results in a specific coating on the steel, combines annealing and hot-dip galvanizing.
  • Hot-dipping and rapid annealing are used to execute the galvanization process, which results in a matte grey finish.
  • Galvannealed sheet metal is an iron alloy product in which the base metal is hot-dip coated, then heated to induce alloying between the molten zinc coating and the steel.
  • The resultant finish is a dull matte surface.
  • The resulting surface is ideal for paint adhesion, and the technique is amenable to welding.


  • This method is similar to hot-dip galvanizing as it is carried out at the beginning of manufacturing.
  • As the name implies, pre-galvanizing is a procedure that immediately prepares the metal for galvanizing by heating and rolling the sheet metal through a cleaning chemical.
  • The metal is then pushed into the zinc-melting pool and is quickly pulled out.
  • The main benefit of this process is that sheet metal coils may be galvanized more uniformly and quickly than with the conventional hot-dipped method.

Benefits of galvanized sheet metal

There are many benefits of galvanized sheet metal. Some of the top benefits of galvanized sheet metal are listed below:

  • Durability
  • Cost-effectiveness
  • Faster turnarounds
  • Complete coverage
  • Reliable and hygienic coating


Coating performance and life are dependable and predictable. Galvanized sheet metal is more durable than conventional steel, which is one of its main advantages. The coating helps in preventing any form of corrosion and rusting on the material. This makes it considerably less probable that you’ll ever need to replace the material, which is advantageous for most construction projects.


Galvanizing offers a significantly lower cost than using other types of coating techniques. Galvanized steel should be used instead of different types of steel if you want to reduce expenses on construction projects. When you use this material in excess, it helps you save a lot of money.

Faster turnarounds

It is a very rapid process of coating steel. Surface preparation, coating, and inspection don’t take up any extra time on-site. Once the components have been assembled, they are ready for utilization or the subsequent manufacturing phase. This is crucial to ensuring that your project runs well and that you provide your client with maximum satisfaction.

Complete coverage

Galvanized metal is protected in all directions, including corners and complex areas. No other coating is required after the galvanizing process. It implies that once the galvanized steel is set up, you won’t have to waste time adding further protection to other elements of the project.

Reliable and hygienic coating

Surface maintenance is simple with galvanized steel. This material is simple to clean and maintain if you work on a project requiring daily washing. It is more important than ever, particularly during the challenging circumstances we are all experiencing. A hygienic material selection ensures that everyone remains healthy and safe during working hours.

Applications of galvanized sheet metal

Galvanized sheet metal may be used for a wide range of applications, including drinking water pipelines, nuts, bolts, and automobile bodies. Its widespread use is a result of its low cost, durability, and ability to produce strong coats. If your part or component will be exposed to adverse environmental conditions, this is one of the finest options.

Some of the applications of galvanized sheet metal are listed below:

  • Automotive industry
  • Construction industry
  • Telecommunication industry
  • Wind and solar industries

Automotive industry

Zinc-coated car bodies are now typical in the auto part manufacturing process. However, it was formerly limited to high-end vehicles. The “body in white,” which is entirely comprised of galvanized steel, accounts for approximately 80% of the car’s body. Galvanized steel is a valuable metal for automobile prototypes since it enables companies to offer “anti-rust warranties.”

Construction industry

For commercial or domestic applications, galvanized steel has been an industry standard for more than a century. It is utilized for building in addition to being durable owing to its appealing appearance. Galvanized steel has a modern aesthetic because of its “shine,” and architects commonly employ it in their design ideas.

A range of secondary structural components, and materials for outdoor elements such as fencing, rails, poles, and more are also formed from this material. Duct work and piping are also fabricated out of galvanized sheet metal.

Telecommunication industry

In the telecommunications industry, phone lines are challenging to repair because they’re long and sometimes impossible to access. Phone wire and equipment boxes can be made of galvanized steel, lowering the danger of damage and eliminating the need for maintenance.

Wind and solar industries

Solar installation must run regularly once deployed, and any maintenance or repairs will be inexpensive. Galvanized steel is frequently utilized in solar systems because of its capacity to resist corrosion. It is also well renowned for being “environment-friendly” because it does not generate pollutants and promises decades without maintenance. Hot-dip galvanized steels give corrosion-resistant enhanced protection that often lasts for decades, even when exposed to the severe environment of rooftop solar installations.


What is the difference between galvanized sheet metal and stainless steel?

Galvanized sheet metal Stainless steel
Galvanized steel has a zinc coating that establishes a barrier between the molten steel, and the air and moisture, thus, preventing corrosion. Stainless steel is steel that has been alloyed with at least 10% chromium to produce a corrosion- and bacteria-resistant alloy. It is ultimately the most durable option.
Galvanized steel stands up to water, except salt water. Stainless steel is strong, corrosion-resistant, and rust-resistant when in contact with the elements of salt water.
Most structural steel welders will have no problems while working with galvanized steel. Welders who work with stainless steel need specialized skills and also ensure that all filler material match with steel being welded.
It is used in pipes and fitting residential homes, as well as, air conditioning equipment, fencing, and hardware such as screws, bolts, and other small parts. It is often used in the fabrication and welding of skyscrapers, sculptures, railways, and cars.

Is galvanized metal cheap?

Galvanization provides an incredibly high-performance coating that eliminates the need to paint your metal regularly. As a result, you do not need to be concerned about the high maintenance costs of these metal elements, because the galvanization coating can last for a very long period of time. Regarding cost, galvanized steel is often less expensive and more frequently accessible. Whether you’re looking for fasteners, gaskets, screws, hinges, etc. it usually costs less than stainless steel. This makes it a good choice for budget-conscious consumers and companies.


To summarize, we hope you have a sound knowledge of galvanized sheet metal and its types. The world is progressing very much in every field with the rise in demand for new products and prototypes.

Worthy Hardware is a CNC manufacturing and sheet metal fabrication company,including CNC machining services,CNC milling services, CNC turning services, laser cutting services and stamping services.Call us +86-76989919645 or email us [email protected] for more discounts for your projects.