A global team of researchers has found a way to create bendable glass using lasers fired at crystalline aluminium oxide. In their research published in the journal Science, the group explains their technique and the features of the glass they made. Lothar Wondraczek with the University of Jena has issued a companion piece in the same journal issue summarising the history of scientists trying to overcome the brittleness of glass.
Glass is rather strong, but only up to a point; it is also very hard. If you drop a drinking glass, it will possibly break on the floor. As Wondraczek notes, scientists have been examining ways to make the glass less brittle during the time people have been making glass. The bendable glass would mean drinking glasses that endure a fall or smartphone screens that do not break. In this fresh effort, the researchers say they have taken a step in the direction of that goal.
Ordinary glass is made from oxygen and silica, and it is identified as an amorphous solid—a position in which a material’s molecules are locked together—in the case of glass, in a random manner. It is transparent because photons can pass through it without intermingling with any of the electrons in the glass. In this innovative effort, the researchers used crystalline aluminum oxide rather than sand to make some tiny glass models. To do so, they shot intense bursts of laser light at a tester to turn it into a purple plasma. The material was then let to cool on a substrate.
Experimenting of the resulting material (sheets two micrometers wide and 60 nanometers thick) revealed it to be transparent and much less brittle than ordinary glass. The sheets were also stretchable and bendable. The researchers found they could extend them up to 8 percent and squeeze them to half their length.
The researchers also took a careful look at their bendable glass using an electron microscope. Using what they discovered, they made computer simulations of the material they had made to better understand its properties. The sample showed that the glass had a very compactly packed network of atoms that was defect-free, making it bendable. Its atoms were able to change places when visible to pressure.
More work is essential before the bendable glass can be commercialized—it is still not evident if the process could be used to make larger sheets of glass, or if it is even responsive to manufacturing.