Cast iron has played a significant role in the industrial revolution and throughout history due to its strength, malleability, and affordability. This naturally occurring metal has been formed and forged into tools, weapons, and even religious icons, from Ancient Greece and Rome to early industrial Europe and America. Today, cast iron is still a popular material for a variety of uses, from cookware to home decor.
Cast iron is a heated mixture of iron ore, coke (a form of carbon), and limestone. It is poured into moulds and heated until the iron combines with the carbon and the material solidifies. This mixture, known as wrought iron, is then heated and poured again, creating a new form of iron known as cast iron. This cast iron is made up of a combination of iron and carbon, with other elements such as manganese or silicon also present.
When heated and poured into molds, cast iron hardens to form an incredibly strong metal, even when machined or further shaped. The form of the metal makes it highly durable yet still malleable, allowing it to be machined and shaped into almost any object. This makes it invaluable for metalworking and manufacturing applications. Cast iron is resistant to corrosion and does not rust easily, allowing it to be used for many outdoor and wet applications, such as plumbing and drainage systems.
Cast iron can be machined and shaped into a number of shapes, most notably a ‘moulded’ shape, or a complex form with a very precise shape. The two processes are known as casting and forging. The actual process of producing a cast iron product is known as casting. During this process, liquid iron is poured into a heated mould and left to cool and form the desired shape. After the object has cooled, the mould is broken open to reveal the cast iron object.
Forging is another process for producing cast iron objects. This involves taking a piece of already-cast iron and heating it until it’s malleable, then shaping it with a hammer and anvil. The resulting object is even stronger than traditional cast iron.
Moulded cast iron grates and covers, gears, engine and machine components, and hand tools are just a few of the everyday items that are made from cast iron. In addition to its practical uses, cast iron is a popular choice for architectural details, decorative objects and accents, sculptures, and jewelry.
No matter what the application, cast iron is and will always remain an essential material for many industries. Its strength, malleability, ease of shaping and corrosion resistance ensure its importance in the modern world.
