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Posted on: 1/16/2013 12:00:00 AM... Technologically valuable ultrastable glasses can be produced in days or hours with properties corresponding to those that have been aged for thousands of years, computational and laboratory studies, recently published in Nature Materials, have confirmed.

Aging makes for higher quality glassy materials because they have slowly evolved toward a more stable molecular condition, a process that can take thousands of years. Researchers at the universities of Chicago and Wisconsin-Madison raise the possibility of designing a new class of materials at the molecular level via a vapor-deposition process.

Ultrastable glasses could find potential applications in the production of amorphous metals, which are better suited for high-impact applications than crystalline metals because of their superior strength.

Researchers have been growing materials for decades via vapor deposition in a vacuum chamber. In this process, glasses are created when a sample material is heated, then vaporizes, and finally condenses and grows atop an experimental surface. The Chicago and Wisconsin-Madison researchers discovered that glasses grown this way on a specially prepared surface that is kept within a certain temperature range exhibit far more stability than ordinary glasses.

The team speculated that growing glasses under these conditions gives molecules extra room to arrange themselves into a more stable configuration, and used computer simulations to confirm that they had actually produced a highly evolved, ordinary glass rather than an entirely new material.

"It had been believed until now that there is no correlation between the mechanical properties of a glass and the molecular structure; that somehow the properties of a glass are ‘hidden’ somewhere and that there are no obvious structural signatures," the researchers noted. "What we found here is that there are actually differences. It's just that you had to create better glassy materials. Once you create these materials, you see that the structure, and the differences between ordinary and stable glasses are clearly there and are actually pronounced."

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• Access "Ultrastable Glasses from In Silico Vapor Deposition"

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