Inspiration from Nature's body armours – A review of biological and bioinspired composites

Designing and manufacturing multi-functional, lightweight and high-performance body armour materials and assemblies have attracted intense attention recently due to fast-growing military applications. There is an urgent need to reduce the weight and increase the flexibility of body armours without compromising their ballistic protection capability. Natural/biological armour materials and assemblies offer remarkable properties that can inspire the design of lightweight, flexible and tough body armours. In this paper, a systematic review is conducted to identify the structural-mechanical characteristics of selected biological armour systems such as nacre from mollusc shells, conch shells and fish scaled skin. Other biological structures with the potential for ballistic protection have also been investigated, including crustacean exoskeletons and compact bone, which possess structures with important features and properties that may inspire the development of future soldier armours. The techniques and methodologies available for the analysis, fabrication and experimental investigations of bioinspired armour composites and systems are also reviewed in detail. The investigations that have been found to be most relevant to the development of bio-inspired armour systems for dynamic impact resistance have also been discussed. This discussion can inspire the design of lighter and flexible bio-inspired armour systems that are more efficient in resisting ballistic attacks.