Alloys are mixtures containing at least one metal. We use metals for many jobs in our technological world and sometimes a metallic element just won’t cut it. Take iron – whilst extremely strong, it is also very brittle…not something you want to build a bridge out of. Add in a little carbon and you make steel – an alloy with the strength of iron but it not brittle.
Alloys contain atoms of different sizes, which makes it more difficult for the atoms to slide over one another. This makes alloys harder than the pure metal.
Certain mixtures are even more impressive. Mix nickel and titanium and you get Nitinol, a smart alloy used to make spectacle frames. If you bend your glasses (let’s say, by sitting on them…again) just pop them into hot water and the frame returns to its original shape.
Fast Fact: Nickel-Iron alloys are common in meteorites.