When asked to think of a brittle material, many people will likely envision glass, and possibly hear the all-too-familiar sound of it shattering. In the future that may change though, thanks to researchers at McGill University and mollusk shells.
The shell of a mollusk is 95% chalk, which is a very brittle material on its own, yet these shells are resilient. The source of this resilience comes from the nacre, or mother of pearl that coats the inner shells, which is comprised of microscopic tablets. Trying to build a material out of similar tablets has proven very difficult, so the researchers decided to instead engrave a pattern similar to that of nacre onto a glass slide. This increased the toughness of the glass by a factor of 200, and by having the engraved cracks resemble wavy lines, they will not propagate into larger cracks. The researchers also filled the cracks with polyurethane, but this is not necessary to toughen the glass.
The researchers plan on continuing this research by seeing what other materials they can toughen this way, including ceramics and polymers. Of course just toughened glass could prove very useful, to protect it from shattering in its many applications.
Source: McGill University