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On July 28, 2014

Inside a lab in Straumanis-James Hall, graduate student Erica Ronchetto, CerE’11, is systematically breaking soda lime silicate glass — the kind found in most bottles, windows and light bulbs — in hopes of finding ways to make it stronger.

Ronchetto begins by drawing molten glass into thin flexible fibers, not much thicker than a human hair. The process looks like dipping honey from a jar. She bends the fibers and clamps them into a device that squeezes that bend until the fiber snaps, then measures its breaking point. During the process, she exposes the fibers to varying temperatures and humidity levels to see how these variables change that breaking point.

Water is key to the weakness of the glass.

“Humidity in the air causes glass strength to degrade,” Ronchetto says. “It can worsen fatigue and speed up aging.”

“If glass is exposed to humidity long enough, defects will begin to form on the surface,” adds Richard Brow, Curators’ Professor of materials science and engineering. “Those defects eventually lead to weakness. That’s why the same piece of glass will be stronger in Minnesota in the winter than it would be in Louisiana in the summer. It all comes down to humidity.”

By studying the chemical composition of the glass, they hope to eventually modify its surface to reduce the aging and fatigue water can cause.

The end result, Brow and Ronchetto hope, is a stronger, lighter-weight glass that lasts much longer than today’s glasses.

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On July 28, 2014. Posted in Features, Summer 2014