If you have ever worked with or shopped around for metal you may have heard the term ferrous and non-ferrous, but which term is correct when it comes to cast iron? Ferrous metals have iron, while non-ferrous ones don’t. But it’s not just about iron presence; each type has special properties suited for different uses, making them ideal for specific situations.
What exactly is ferrous metal? Well, it’s any metal that has iron in it. Because of this iron content, ferrous metals tend to be magnetic, strong, and tough. That’s why they’re commonly used for building structures, large pipes, industrial containers, and various construction and engineering projects. The term “ferrous” comes from Latin and essentially means metal-containing iron. If a metal has only a small amount of iron in its composition, it’s not classified as ferrous. Ferrous metals are primarily identified by their magnetism and since iron is magnetic, ferrous metals exhibit magnetic properties as well. Additionally, the presence of iron contributes to enhanced hardness and strength in these metals. However, it’s important to note that metals consist of various alloying elements, leading to differences in their appearance and behaviour.
Another thing about ferrous metals is their high carbon content, which can make them more susceptible to rust. However, there are two exceptions to this rule: stainless steel, which has a lot of chromium in it, and wrought iron, which is mostly pure iron.
Common properties associated with ferrous metals include durability, strong tensile strength, good electrical conductivity, limited corrosion resistance, recyclability, and typically being magnetic.
Ferrous metals include
Cast Iron
Stainless Steel
Carbon Steel
Engineering Steel
Wrought Iron
Non-Ferrous Metals
But what exactly is non-ferrous metal? Well, it’s any metal that doesn’t have iron in it. Unlike ferrous metals, these alloys are more flexible and lighter, making them handy when strength needs to be balanced with weight, like in the aerospace industry.
Non-ferrous metals come in various types, primarily pure metals, or alloys without any iron. They’re mostly not magnetic, which sets them apart in terms of magnetic properties.
Apart from metals like aluminium, copper, lead, zinc, and tin, non-ferrous metals also include precious ones like gold and silver, often used for their aesthetic appeal.
Because they lack iron, non-ferrous metals are less prone to rust and corrosion, making them great for things like piping, gutters, roofing, and outdoor signs. Their non-magnetic nature also makes them essential for electronic and wiring applications.
Non-ferrous metals are a diverse group that includes:
Aluminium: Known for being lightweight, sturdy, and easily moulded.
Copper: A metal that conducts electricity well and is highly flexible.
Lead: Heavy and soft, with a low melting point and strength.
Tin: Often used to prevent corrosion on steel, it’s soft and malleable with low tensile strength.
Zinc: With a low melting point and medium strength, it’s used in galvanising to protect against rust.
Brass: Mainly a blend of copper and zinc, its composition can vary depending on added elements.
Aluminium Alloys: These are mixtures of aluminium with other elements to enhance its properties, particularly strength.
Non-ferrous metals have been used extensively throughout history. For instance, copper and bronze played pivotal roles in advancing civilisation from the Stone Age to around 1700 BCE, when people began mining copper and tin to create bronze weapons. Today, these metals have a wide range of uses, including construction, toolmaking, electrical wiring, vehicle engines, pipelines, containers, and even kitchen utensils.
