Structure and Mechanical Performance of Teleost Fish Scales Journal Article uri icon



  • ABSTRACTIn this work, we have studied the structure and mechanics of fish scales from striped bass (Morone saxatilis). This scale is about 200-300 μm thick and consists of a hard outer bony layer supported by a softer cross-ply of collagen fibrils. Puncture tests with a sharp needle indicated that a single fish scale provides a high resistance to penetration which is superior to polystyrene and polycarbonate, two engineering polymers that are typically used for light transparent packaging or protective equipment. Under puncture, the scale undergoes a sequence of two distinct failure events: First, the outer bony layer cracks following a well defined cross-like pattern which generates four “flaps” of bony material. The deflection of the flaps by the needle is resisted by the collagen layer, which in biaxial tension acts as a retaining membrane. Remarkably this second stage of the penetration process is highly stable, so that an additional 50% puncture force is required to eventually penetrate the collagen layer. The combination of a hard layer that can fail in a controlled fashion with a soft and extensible backing layer is the key to the resistance to penetration of individual scales.

publication date

  • January 1, 2012

Full Author List

  • Zhu D; Szewciw L; Vernerey F; Barthelat F

Other Profiles

Additional Document Info


  • 1420