Researchers at McGill’s department of Mechanical Engineering have developed a new technique that increases the toughness of glass by a factor of 200.
Led by Francois Barthelat and current postdoctoral researcher Mohammad Mirkhalaf, the research was inspired by seashells. Seashells are apparently the “perfect models of nature to mimic, because of their very complex architecture.” Seashells (for example mollusk shells) are composed of mainly brittle ingredients, like chalk, but their inner layer contains mother of pearl, a natural material composed of microscopic patterns known to be extremely strong and tough. The team focused their work on how seashells behave and deform, and specifically studied the internal weak boundaries of this inner layer. Using their understanding of these boundaries, the research team used lasers to engrave jigsaw-like networks of 3D micro-cracks into glass slides, mimicking these weak boundaries.
The technique amplified the toughness of the glass, overcoming its main downfall of being brittle. The micro-cracks served as a control mechanism for stopping other cracks from branching and becoming larger, absorbing energy from the impact in the process. By segmenting the glass material and creating weak interfaces, they were able to guide and localize the damage.
So what would happen if you were to drop this new, tougher glass? It would deform a little and absorb the energy from the impact rather than shattering into little pieces, the glass just bends or dents upon impact. There are height limitations naturally, as the glass would shatter if dropped from great heights however, they are trying to improve this through further research.