Fabrication, testing and modeling of a new flexible armor inspired from natural fish scales and osteoderms

作者：Ravi Kiran Chintapalli, Mohammad Mirkhalaf, Ahmad Khayer Dastjerdi, François Barthelat · 发表于：Bioinspiration & Biomimetics · 年份：2014 · DOI：10.1088/1748-3182/9/3/036005 · 被引用次数：128 · 研究领域：Calcium Carbonate Crystallization and Inhibition、Silk-based biomaterials and applications、Cellular Mechanics and Interactions

Crocodiles, armadillo, turtles, fish and many other animal species have evolved flexible armored skins in the form of hard scales or osteoderms, which can be described as hard plates of finite size embedded in softer tissues. The individual hard segments provide protection from predators, while the relative motion of these segments provides the flexibility required for efficient locomotion. In this work, we duplicated these broad concepts in a bio-inspired segmented armor. Hexagonal segments of well-defined size and shape were carved within a thin glass plate using laser engraving. The engraved plate was then placed on a soft substrate which simulated soft tissues, and then punctured with a sharp needle mounted on a miniature loading stage. The resistance of our segmented armor was significantly higher when smaller hexagons were used, and our bio-inspired segmented glass displayed an increase in puncture resistance of up to 70% compared to a continuous plate of glass of the same thickness. Detailed structural analyses aided by finite elements revealed that this extraordinary improvement is due to the reduced span of individual segments, which decreases flexural stresses and delays fracture. This effect can however only be achieved if the plates are at least 1000 stiffer than the underlying substrate, which is the case for natural armor systems. Our bio-inspired system also displayed many of the attributes of natural armors: flexible, robust with 'multi-hit' capabilities. This...