What is Corten Steel?

Corten steel is also known as weathered steel which gives a good clue as to where it’s mostly used. It is a group of steel alloys used primarily in exterior building, construction or art installations. They have been designed to negate the need for painting so can be left exposed outdoors in all weather conditions. After a few months, the steel develops a red/orange rusty appearance. Rust is usually something not many people desire but with Corten, the development of the oxidised red/brown layer helps to protect the metal, preventing deeper damage from rust.

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History of Corten

It was first developed in the United States in the 1930s by a company called U.S Steel. The original concept was for a material that could be used to build coal wagons for the railroad. It soon grew in popularity among artists in the fifties and sixties, being used to create many outdoor works of art. There are still many examples of early Corten artwork found around the U.S today in the form of structures and sculptures.

How is it manufactured?

Corten steel is made by combining a specific mix of alloys and steels. It is the combination that gives it fast rusting qualities and its distinctive appearance. It is made from a sheet of around one quarter of an inch in thickness, being both thin but very tough and durable.

What can it be used for?

Many outdoor projects use Corten steel as a material of choice and this includes sculpture. Outdoor sculptures are commonly made from this material due to the fast build-up of rust that gives it a vintage, weathered look and keeps it well-protected. For your own stunning garden artwork, consider Corten Metal Garden Sculptures as a focal point. Corten Metal Garden Sculptures are available to view at http://www.afsculpture.uk/portfolio_page/corten-metal-sculptures/

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How does Corten rust?

Most metals are designed to be as resistant to rust as possible, however Corten encourages rust to form. How does it do this? The rust on Corten forms a protective layer over the surface that you don’t need to paint or treat in any way. When it is new, it is shiny just as you expect steel to look. However, when it’s been exposed to the air for a while, rust begins to form as a yellow streak, before turning orange until after a decade or so has passed, a stunning deep brown/purple hue.

How long will Corten last?

Ideally, it should last for a couple of hundred years if the climate isn’t extreme. Locations by the sea can cause some disintegration of the rust layer as salt eats through it.