Please enable JavaScript to view the comments powered by Disqus. Scientists have created a flexible membrane from a normally brittle complex oxide, and shown that stretching can change its electronic properties.
Our website uses cookies Cookies enable us to provide the best experience possible and help us understand how visitors use our website. Okay, I understand Learn more. Home » Characterization » News » Shattering the image of brittle glass. Shattering the image of brittle glass 14 March Glass has many useful properties: strength, rigidity, and transparency. But, it is also fragile; when it cracks it reveals its brittleness and shatters almost instantaneously.
Contrast that behavior with steel and other alloys, which are tough, but deform and fail easily. Glass is composed of tetrahedral crystals. That these crystals did not achieve regular, repeating crystalline structure does not mean glass is a permanent liquid. My Glass Ceramics prof nearly shot me for saying that in class one day. If it did, it would be like sheetmetal steel, where it dents and deforms instead of shattering.
I would like to point out something else though: The strongest fiber ever tested was a glass fiber drawn and tested in an inert atmosphere. Also, you can take a glass fiber by the ends and bend it into a circle, much like any metal wire. Hence it is elastic. BUT if you touch that same fiber in several places, then try to bend it again it will shatter in your hands. DarkDesire on November 30th, Glass does not freeze in the normal sense.
It just flows more and more slowly. If stiffens because of this. Glass remains quite flexible as evidenced by small fibers. You would have something known as a glass. Glasses have three characteristics that make them more closely resemble "frozen liquids" than crystalline solids.
First, and foremost, there is no long-range order. Second, there are numerous empty sites or vacancies. Finally, glasses don't contain planes of atoms. The simplest way to understand the difference between a glass and a crystalline solid is to look at the structure of glassy metals at the atomic scale.
By rapidly condensing metal atoms from the gas phase, or by rapidly quenching a molten metal, it is possible to produce glassy metals that have the structure shown in the figure below. The amorphous structure of glass makes it brittle. Because glass doesn't contain planes of atoms that can slip past each other, there is no way to relieve stress. Excessive stress therefore forms a crack that starts at a point where there is a surface flaw.
Particles on the surface of the crack become separated. The stress that formed the crack is now borne by particles that have fewer neighbors over which the stress can be distributed. As the crack grows, the intensity of the stress at its tip increases. This allows more bonds to break, and the crack widens until the glass breaks.
Thus, if you want to cut a piece of glass, start by scoring the glass with a file to produce a scratch along which it will break when stressed. Glass has been made for at least years, since the Egyptians coated figurines made from sand SiO 2 with sediment from the Nile river, heated these objects until the coating was molten, and then let them cool. Calcium oxide or "lime" CaO and sodium oxide or "soda" Na 2 O from the sediment flowed into the sand to form a glass on the surface of the figurines.
Sand is still the most common ingredient from which glass is made. Sand consists of an irregular network of silicon atoms held together by Si O Si bonds. If the network was perfectly regular, each silicon atom would be surrounded by four oxygen atoms arranged toward the corner of a tetrahedron.
Because each oxygen atom in this network is shared by two silicon atoms, the empirical formula of this solid would be SiO 2 and the material would have the structure of quartz. In sand, however, some of the Si O Si bridges are broken, in a random fashion.
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