Researchers in Japan have created a type of glass that is stronger than many metals and almost as strong as steel.
The researchers used, what they call, aerodynamic levitation to create glass imbued with extra amounts of an oxide of aluminium. Glass that does not break when dropped or when struck by another object would be useful in a wide variety of applications, from automobile windows, to skyscrapers to smartphones and tablets.
One of the ways to make traditional glass stronger is to add larger amounts of an oxide of aluminium to the mix, specifically, alumina, because it has one of the highest dissociation energies among oxides.However, when more alumina is added to the mix while the glass is being made, silicon dioxide crystals develop where the mix meets the surface that is holding it, making the end product worthless as a glass.
The new process involves causing the mix to be held in the air while it is forming, by pushing it from below with oxygen gas and then using a laser as a spatula to mix the materials together. The end result is a glass with more alumina in it than any other produced –a glass that is transparent, colourless and extremely hard.