Fabrication and Mechanics of Bioinspired Materials with Dense Architectures: Current Status and Future Perspectives

Materials with dense architectures are composed of stiff and strong building blocks that are arranged to interact through energy-dissipative interfaces. Examples of these materials include engineered constructions such as the Abeille vault and highly mineralized natural materials such as tooth enamel. Compared with synthetic materials, natural materials with dense architectures exhibit outstanding mechanical performance, serving as a continued source of inspiration and study. This review details the status of advances in the fabrication and mechanics of bioinspired materials with dense architectures. The fabrication methods include freeze-casting, mineralization, 3D printing, coating-assembling, and laser engraving. Micromechanics of the resulting materials are discussed in tension, flexion, fracture, puncture, and impact. The discussion shows that strength of these materials can be improved by decreasing the size of their building blocks to the nm-mu m range. However, interface hardening mechanisms that are crucial to the spread of deformation and toughness have not yet been implemented at nm-mu m scales although they have been successfully realized for materials with larger building blocks. Future directions to address this and other unmet challenges are discussed throughout the text.