From the earliest discoveries of copper and gold many thousands of years ago to the complex alloys we use today, metal has long been an important material to humanity. We use it to build everything from tiny hair clips to soaring skyscrapers, though we can’t always use the same type. Here are a few common types of metal and why they are used around the world.
What is metal?
While most of us recognise metal when we see it, it’s easy to forget what it really is. Doing away with more complicated scientific definitions, metal is essentially a class of substances known for being opaque, pliable, lustrous and able to be melted down. They are also good conductors of heat and electricity.
Iron is a common metal that was once widely used in its basic form, even to build structures like the Eiffel Tower. These days, iron is usually used as a key ingredient to create more versatile types of metal, though it is still used for specialised applications such as cookware and supports for heavy machinery.
An alloy isn’t a pure metal in itself, but rather a type of metal made by combining two or more pure metals to give it certain properties, such as lighter weight, greater strength or resistance to corrosion. If you see a metal with alloy in its name, you’ll know it’s been mixed with certain metallic substances for a specific purpose.
While pure iron is strong, it’s also heavy and prone to corrosion. Steel is created by mixing iron with carbon, resulting in a metal that’s strong, corrosion resistant and relatively easy to work with. This makes steel an alloy (and one of the most common) though its popularity makes it a category in and of itself.
Aluminium has only been around since the 1800s, which isn’t long in the world of metals. This metal is incredibly strong given its lighter weight, which makes it a popular aerospace metal for planes, helicopters and even spacecraft. However, it’s also used for more simple applications like soft drink cans and foil sheets for cooking.
It’s easy to forget, but gold is indeed a metal! It’s been a cherished metal for thousands of years thanks to its beautiful appearance, resistance to corrosion, perceived value and relative rarity, even if it’s not as rare as many may think. While it was historically used for currency and now primarily for jewellery, it is also used in electronics given it’s a good conductor of electricity and heat.