At McGill University’s Laboratory for Advanced Materials and Bioinspiration, Professor Francois Barthelat researches natural structures such as nacre and teeth to understand their inherent mechanical properties. Like many material scientists, Barthelat is intrigued by the notion that biology holds the answers to our technological ambitions for more resilient materials.
Barthelat and his team discovered that nacre consists of layers of microstructural blocks that are loosely held together by weak boundaries. The scientists sought to model these microfissures in glass to test its mechanical performance and used a laser to engrave networks of three-dimensional cracks in borosilicate glass slides. They also filled the gaps between the jigsaw-like patterns with polyurethane, intended to function as a kind of cement.
The resulting sample far outperformed standard glass, with over two hundred times the toughness of the untreated material. This durability imparts the new glass with more flexibility than the typical version, which is brittle. The secret lies in the strategic use of weak boundaries—as seen in expansion joints used in buildings—to diminish crack propagation and material failure. This successful approach represents a pathway for toughening a variety of ceramic materials based on similar natural principles.
Contact: McGill University Department of Mechanical Engineering, Montreal, QC, Canada.
For more information, see Transmaterial Next: A Catalog of Materials that Redefine Our Future