So you’ve finally taken a moment to think “how is steel made?”
Steel is everywhere throughout our lives, but we often take it for granted. It’s one of the most common building materials in the world. Your pots, pans, and appliances are made from steel. Your car is made from steel. There’s even steel in your home, school, or workplace. So, just how do they make steel?
What is Steel Made of?
As you know, steel is a metal. Most metals are natural elements found in the ground, but steel is nowhere to be found in the periodic table. That’s because it’s an alloy, which is a combination of two or more different metals. Metals are divided into ferrous and non-ferrous types of metal. Ferrous metals – like steel – contain iron. Some examples of non-ferrous metals are titanium and copper.
Iron has a lot of impurities in it, including phosphorous, sulfur, and silica. Those impurities make iron weaker. Steel is made through a process that removes the impurities from iron and adds carbon to it. The carbon is what makes steel so tough and durable.
The Process of Refining Steel
Elemental metals such as iron come from ore. Metals are extracted from ore by heating the ore to intense temperatures until it melts; a process known as smelting. Historians believe that steel has been made for thousands of years, but it was the invention of the blast furnace that gave us the steel we know and love today. Other technological improvements have also contributed to durable and powerful steel. These days, most steel is made through a process known as “basic oxygen steelmaking” – or BOS.
Large-scale BOS furnaces are used to blast high-purity oxygen into molten iron ore. The oxygen combines with the impurities in the iron to firm oxides. The oxides then burn off in the form of slag, leaving behind pure iron. The slag is scraped off and other chemical cleaners are added to the mix to help get rid of any remaining impurities.
From there, other elements are added to create the kind of steel necessary. Steel is commonly made with carbon, but it can be made with other elements. For example, chromium can be added to iron to create the stainless steel used for cutlery and surgical instruments. Stainless steel is highly rust-resistant, so it has a long lifespan.
So Now You Know!
Steel is among the most common building materials in the world. That’s because it is so tough and durable. It’s also relatively cheap to produce so it’s popular in the manufacturing of all types of buildings including Steel Buildings Kits. Over 1.3 billion tons of steel are produced each year. Steel is used for all kinds of things, from building materials to automobile frames, ships, bridges, machines, and weapons.
So, now you know how steel is made. It’s an alloy, so it can’t be mined and made by itself. It’s a combination of purified iron and other elements. The iron is melted at an intense temperature to remove impurities, the other element is added (often carbon), and then the finished product is steel.