Flexible Impact-Resistant Composites with Bioinspired Three-Dimensional Solid–Liquid Lattice Designs
Zhanyu Wang, Renheng Bo, Haoran Bai, Shunze Cao, Shuheng Wang, Jiahui Chang, Yu Lan, Ying Li, Yihui Zhang
Abstract
The ubiquitous solid–liquid systems in nature usually present an interesting mechanical property, the rate-dependent stiffness, which could be exploited for impact protection in flexible systems. Herein, a typical natural system, the durian peel, has been systematically characterized and studied, showing a solid–liquid dual-phase cellular structure. A bioinspired design of flexible impact-resistant composites is then proposed by combining 3D lattices and shear thickening fluids. The resulting dual-phase composites offer, simultaneously, low moduli (e.g., 71.9 kPa, lower than those of many reported soft composites) under quasi-static conditions and excellent energy absorption (e.g., 425.4 kJ/m 3, which is close to those of metallic and glass-based lattices) upon dynamic impact. Numerical simulations based on finite element analyses were carried out to understand the enhanced buffering of the developed composites, unveiling a lattice-guided fluid–structure interaction mechanism. Such biomimetic lattice-based flexible impact-resistant composites hold promising potential for the development of next-generation flexible protection systems that can be used in wearable electronics and robotic systems.