Normally when you drop a drinking glass on the floor it shatters. But, in future, thanks to a technique developed in McGill’s Department of Mechanical Engineering, when the same thing happens the glass is likely to simply bend and become slightly deformed.
Bio-inspired glass 200 times tougher than regular glass
That’s because Prof. François Barthelat and his team have successfully taken inspiration from the mechanics of natural structures like seashells in order to significantly increase the toughness of glass.
“Mollusk shells are made up of about 95 per cent chalk, which is very brittle in its pure form,” says Barthelat. “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.”
Previous attempts to recreate the structures of nacre have proved to be challenging, according to Barthelat. “Imagine trying to build a Lego wall with microscopic building blocks. It’s not the easiest thing in the world.” Instead, what he and his team chose to do was to study the internal ‘weak’ boundaries or edges to be found in natural materials like nacre and then use lasers to engrave networks of 3D micro-cracks in glass slides in order to create similar weak boundaries. The results were dramatic.
The researchers were able to increase the toughness of glass slides (the kind of glass rectangles that get put under microscopes) 200 times compared to non-engraved slides. By 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 stop the cracks from propagating and becoming larger. They then filled these micro-cracks with polyurethane, although according to Barthelat, this second process is not essential since the patterns of micro-cracks in themselves are sufficient to stop the glass from shattering.
The researchers worked with glass slides simply because they were accessible, but Barthelat believes that the process will be very easy to scale up to any size of glass sheet, since people are already engraving logos and patterns on glass panels. He and his team are excited 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,” says Barthelat. “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.”
katherine gombay | Newswise
Decoding cement's shape promises greener concrete
08.12.2016 | Rice University
Scientists track chemical and structural evolution of catalytic nanoparticles in 3-D
08.12.2016 | DOE/Brookhaven National Laboratory
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine