Military
August 2008
Scale construction in primitive fish may trigger ceramic armor redesign
We suspect that body armor designers at companies like CoorsTek and Ceradyne are already following up on a recent discovery by MIT engineers. These investigators have been studying Polypterus senegalus, a freshwater fish with a unique armor system that was apparently common in water-dwellers million of years ago. P. senegalus is currently found in Africa.
Using nanotech measurement techniques, the group unraveled the orientation, sequence and bonds that exist in each of the fish’s multi-layered scales, each layer being about 100 microns thick. These structurally-efficient scales provides P. senegalus with a tough layer of protection that can protect it from even the teeth of a predator.
By testing individual samples, researchers learned that the fishes’ scales, when put under stress, have the ability to stay confined by forming circular cracks around the contact point. This contrasts with typical fish scale – and body armor – breakdowns that occur when cracks spread to adjacent areas leading to catastrophic failure.
"Such fundamental knowledge holds great potential for the development of improved biologically inspired structural materials, for example soldier, first-responder and military vehicle armor applications," said lead author Christine Ortiz, an associate professor in MIT's Department of Materials Science and Engineering.
"Many of the design principles we describe – durable interfaces and energy-dissipating mechanisms, for instance – may be translatable to human armor systems," Ortiz added.
