If you're installing automated gates, you're likely to have come across different kinds of materials that they're commonly made from such as iron, stainless steel and galvanised steel. So what are all of these substances?

Carbon Steel: Wrought and Cast Iron

Two metals that you might see in gates are wrought and cast iron. Both of these forms of carbon steel are produced by mixing iron and carbon with other materials. The higher the carbon content within the mix, the more brittle it is. Conversely, the lower the iron, the more malleable it is. Wrought iron, typically used for decorative work, is a form of low-carbon steel. Because it has little carbon, it is pliable enough to be hammered and worked into various ornate designs while it is still hot. Cast iron, however, due to its higher carbon content, is too brittle to be worked into shape in this way. So cast iron objects are created by pouring the molten metal into casts and moulds that produce the final forms. Iron can tend to corrode, so gates constructed from either of these kinds are usually painted or powder-coated to protect the inner base metal from rust. 

Alloy Steel: Stainless Steel

Stainless steel is another possibility for gates. It too is comprised of iron and carbon blended with other elements. But, crucially, one of those elements is chromium, which provides rust protection. Stainless steel includes from 10 to 30 per cent of this naturally anti-corrosive ingredient. Different grades of stainless steel are manufactured by mixing slightly different combinations of elements. But even though the strength varies between the grades, stainless steel is generally durable and an ideal gate material.

Galvanised Steel

Galvanising is a treatment that protects metals from corrosion. Typically, during this process, a metal object is immersed in a bath of molten zinc. Once it's removed, the zinc hardens, forming a uniform coating across the surface. Because the item is fully immersed, the zinc covers every corner, crevice and inaccessible area. This film protects the inner metal from corrosion.

Galvanised steel, then, has undergone this treatment that prevents moisture from coming into contact with the steel itself. Typically, stainless steel wouldn't be galvanised as it is already rust resistant due to its chromium content. But other types of steel might be galvanised and made into fencing and automatic gates.

Wrought iron, cast iron and steel all make excellent gates. While stainless steel resists rust, iron and other steel types will need either painting, powder-coating or galvanising to create a protective shield over the inner metal.