Why doesn’t glass crystallize?
Glass isn’t characterized as either a liquid or a solid. Unlike other truly solid objects, glass doesn’t form a crystal structure when it achieves a room temperature. At the same time, it also doesn’t retain the characteristics of a liquid when it cools. Instead, glass gets “stuck” in what’s known as an amorphous state – neither solid nor liquid, but something in between.
German researchers at the Johannes Gutenberg University Mainz used a light technique to try to explain why glass doesn’t crystallize like other solids do. For years, scientists have been split on what happens when glass hardens. Some scientists believe that the cooling glass molecules “freeze” their thermal motion, which prevents them from attaining a crystallized form. Others believe that the glass molecules clump together as they cool, which produces the same result – a non-crystalline structure.
The scientists discovered that in their liquid state, materials form hard spheres. The concentration of the hard spheres is important, because hard spheres can form either crystals or glass under the right conditions.
In their experiments, the scientists discovered that the concentration of hard spheres is the key to determining whether crystallization or glass formation will occur. A lower concentration of hard spheres leads to crystallization, where a higher concentration of hard spheres in the molten liquid leads to the formation of glass. As one scientist explained, the higher concentration of hard spheres actually prevents crystallization, and results in the formation of glass.
The research is important because it can be applied to other amorphous materials. In addition, being able to impose a crystalline structure on glass may lead to important changes in the strength and performance of glass under specific circumstances. The random arrangement of particles in cooled glass explains why glass shatters or breaks in random pieces, and why glass can contain weak areas that make it more prone to spontaneous breakage.
Regardless of the material state of the glass it coats, Glassprimer™ glass paint cures within 24-72 hours of application. Unlike other paints that either won’t dry or won’t stick, Glassprimer™ glass paint forms a permanent bond with the glass surface, and provides exceptional UV resistance for years.
If you’d like more information about Glassprimer™ glass paint, please visit the rest of our site. If you’d like to purchase Glassprimer™ glass paint, please visit our online store .
Photo Credit: Alexey Kljatov, via Flickr.com