Steel is a metal that is an alloy of iron and carbon which contains small amounts of silicon, phosphorus, sulphur, and oxygen. This metal is known to rust—return to its original state of iron oxide—as it is exposed to elements like water and oxygen, but this can be prevented by applying a variety of topcoats including paint, enamel, and chromium. Steel is malleable and durable and has great tensile strength and thermal conductivity. End uses for steel include magnetic markerboards, ceiling tiles, woven metal screens, wall tiles, and refrigerators. It is also used to create swords, bridges, automotive parts, and skyscrapers.
There are a variety of steels that are produced and used according to their desired end use. These include carbon steels, alloy steels, stainless steels, and tool steels. For architectural and design purposes, carbon steels are most common. According to the World Steel Association, low carbon steel—sometimes referred to as wrought iron—is easy to work with and as a result is often used for decorative products that include fences and lamp posts. Medium carbon steel is stronger and can be used on a larger scale for constructions such as bridges, while high carbon steel is most often used for wires. Also referred to as cast iron, ultra-high carbon steels are very hard and brittle, and are often used for kitchenware items such as pots and pans.
Steel can by abstracted in two ways, blast furnace- basic oxygen furnace (BF-BOF) or electric arc furnace (EAF). With the BF-BOF method, the iron ores are reduced to dust and then converted to steel using the furnace. This method is most common with newly abstracted steel or with steel that has less than 30-percent recycled content. The EAF method is used to melt recycled steel and add any alloys that are needed in order to balance its composition. Both of these furnace methods result with steel that can be casted and rolled and turned into coils, bars, sheets, and more. As is the case with many other metals, steel can be recycled and reused. End products that include recycled steel will not lose any of their original properties.