The difference between ferrous and non-ferrous metals lies in the name itself. The term “ferrous” comes from the Latin word “ferrum” , which means iron. Non-ferrous metals are those that lack any iron component, meaning that some of them may be pure metals, unlike the ferrous type that is comprised entirely of alloys. Non-ferrous metals have been around since the beginning of civilisation. Copper was discovered in 5,000 BS, marking the end of the Stone Age and beginning of the Copper Age, and the invention of bronze later was the inception of the Bronze Age.
The lack of an iron component carries a number of benefits that make non-ferrous metals useful in places that ferrous metals simply won’t do the job. As iron is prone to rust, non-ferrous metals can be used for things that require repeated exposure to water and the other elements, so they’re the perfect choice for gutters, pipes, roofing elements, ship parts, as well as street and highway signs, among others. They are also commonly used as a coating over steel in order to help prevent erosion in places where the harder ferrous metal is more obviously needed.
Non-ferrous metals are also softer and highly malleable and can be moulded into whatever shape you want fairly easily, making them perfect for tools that need to look a very specific way. They’ll fit into place much easier and faster than ferrous metals. And since magneticity isn’t always a good thing, such as in the case of electronic equipment, their lack thereof makes them the perfect choice for wiring.
The most common types of non-ferrous metals include:
- Aluminium
- Copper
- Lead
- Zinc
- Tin
Types of ferrous metals
Mild Steel
Mostly used for nuts and bolts, building girders, car bodies, and gates, among others, mild steel is a very ductile and malleable metal. Its flexibility makes it a very versatile material, though it’s important to keep in mind that it can rust very quickly.
Cast Iron
Cast iron is most frequently used for car brake discs, car cylinders, metalwork vices, manhole covers, machinery bases, etc. It is a very sturdy and strong type of metal , but is also very brittle. It is predominantly comprised of re-melted pig iron, with small amounts of other metals. Its iron content is 93%, with 4% being carbon.
High-carbon steel/Tool steel
Most often used for hand tools like screwdrivers, hammers, chisels, saws, spring and garden tools, high-carbon steel, commonly known as tool steel, is a very strong and hard metal, mostly resistant to abrasion. Other names for it include medium steel. Its carbon content is 1.5%.
Stainless steel
Stainless steel is most often found in kitchen tools. From kitchen sinks to cutlery, teapots and cookware, among others, but it’s also prevalent in surgical instruments. It owes its name to the fact that it has a very high resistance to wear and water corrosion and rust. Its an iron alloy with an 18% chromium, 8% nickel and 8% magnesium content.
High-speed steel
As the name might suggest, high-speed steel is mostly used for tools that will be involved in tasks happening at high speeds and temperatures, so drill bits, lathe tools, and milling cutters on milling machines. It has a high tungsten, chromium, and vanadium content. It is very brittle, but also very resistant to wear.