McGill University Researchers Develop Shatter-Proof Glass Made FromSeashells

Amazing Info's | Inspired from the mechanics of natural structures similar to seashells in order to extensively increase the toughness of glass, Professor Francois Barthelat and his team of researchers at McGill University of Mechanical Engineering developed a technique to toughen glass so that it doesn’t break, instead it will slightly deformed when dropped.

Barthelat and his team examined nacre’s interior fragile boundaries and compared its structure to miniature Lego blocks.

“Mollusk shells are made up of about 95 percent chalk, which is very brittle in its pure form. But nacre, or mother-of-pearl, which coats the inner shells, is made up of microscopic tablets that are a bit like miniature Lego building blocks, is known to be extremely strong and tough, which is why people have been studying its structure for the past twenty years,” Barthelat explained.

According to Barthelat, earlier attempts to rebuild the structures of nacre have proved to be tricky.

“Imagine trying to build a Lego wall with microscopic building blocks. It’s not the easiest thing in the world,” he said.

He and his team of researchers study the internal weak boundaries or edges to be found in natural materials similar to nacre and then use lasers to engrave networks of 3D micro-cracks in glass slides in order to create similar weak boundaries.

The researchers were able to enhance the toughness of glass slides, 200 times compared to non-engraved slides. With engraving networks of micro-cracks in configurations of wavy lines in shapes similar to the wavy edges of pieces in a jigsaw puzzle in the surface of borosilicate glass, they were able to prevent the cracks from propagating and becoming larger. They then filled these micro-cracks with polyurethane, although Barthelat stated that the second process is not essential as the patterns of micro-cracks in themselves are sufficient to stop the glass from shattering.

The researchers worked with glass slides basically since they were accessible, however Barthelat believes that the process will be very easy to scale up to any size of glass sheet, as people are already engraving logos and patterns on glass panels. He and his team are eager about the work that lies ahead for them.

“What we know now is that we can toughen glass, or other materials, by using patterns of micro-cracks to guide larger cracks, and in the process absorb the energy from an impact. We chose to work with glass because we wanted to work with the archetypal brittle material. But we plan to go on to work with ceramics and polymers in future. Observing the natural world can clearly lead to improved man-made designs,” Barthelat added.