How Is Steel Made?

Steel production begins with iron ore (primarily iron oxides), which is smelted in a blast furnace at about 1,500 °C with coke (processed coal) and limestone. The coke acts as both fuel and a reducing agent, stripping oxygen from the iron oxide to produce pig iron, which contains about 4% carbon — too brittle for most uses. The pig iron is then transferred to a basic oxygen furnace (BOF) or electric arc furnace (EAF), where oxygen is blown through to reduce the carbon content to 0.2-2.1%, producing steel. Alloying elements like chromium (for stainless steel), manganese, nickel, or vanadium can be added to achieve specific properties.