Limpets, aquatic snail-like creatures housed in a conical shell, have some extremely strong teeth. On a day-to-day basis, limpets mostly hang around sponging food from rocks, piers and other craggy materials along the seashore. As the waves buffet these creatures, though, what’s stopping them from being dislodged? It turns out it’s their teeth.
Built from nanostructures made of goethite nanofibers bound up in a soft protein case, limpet teeth have incredible mechanical integrity. In fact, according to the Portsmouth study limpet teeth have a tensile strength ranging from 3.0 to 6.5 GPa, making them far less breakable than A36 steel and a host of other man-made materials. What’s more, limpet teeth also have an incredible property—they exhibit the same degree of strength regardless of how they’re scaled. That property isn’t present in other materials, where growth usually coincides with an increase in material flaws.
“Until now we thought that spider silk was the strongest biological material because of its super-strength and potential applications in everything from bullet-proof vests to computer electronics, but now we have discovered that limpet teeth exhibit a strength that is potentially higher,” said Portsmouth Professor Asa Barber.
Given their incredible strength limpet teeth could find their way into a number of products. Most obviously, limpet teeth could inspire a new generation of fibrous materials with applications in F-1 racing, boat hulls and aircraft fuselage. Even beyond planes, boats and automobiles, high-strength materials have great potential in a wide variety of high-performance engineering situations.
Will limpet teeth cling to their new title as the “World’s Strongest Natural Material” for long? No one knows, but what’s most interesting to me is that nature continues to deliver excellent templates to solve today’s most difficult engineering challenges. I guess several billion years of evolution will do that.
Image Courtesy of University of Portsmouth