A natural energy absorbent polymer composite: The equine hoof wall.

摘要: The equine hoof has been considered as an efficient energy absorption layer that protects the skeletal elements from impact when galloping. In present study, hierarchical structure of a fresh wall and mechanisms are investigated. Tubules found embedded in intertubular matrix forming at microscale. Both tubules areas consist keratin cells, which crystalline intermediate filaments (IFs) amorphous fill cytoskeletons. Cell sizes, shapes IF fractions different between tubular regions. structural differences correlated to mechanical behavior this material tested dry, fully hydrated conditions. stiffness hardness tubule higher than dry samples loaded along wall; however, once hydrated, become stiffer due water these compression loading speed directions also examined, with isotropy strain-rate dependence properties documented. walls, mechanistically serve reinforcement, act support entire prevent catastrophic failure under loading. Elastic buckling cracking observed after wall, no shear-banding or severe cracks even 60% compression, indicating highly properties, without failure, structure. STATEMENT OF SIGNIFICANCE: is be absorbent natural polymer composite. Previous studies showed microstructure some perspective. However, nano- macro-scale well strain rates orientations remains unclear. current study provides thorough characterization correlation behaviors. Energy dissipation identified. findings research could provide inspirations on designs resistant materials.