Design and Characterization of Architected Cellular Composite Material Embedded with Strain Rate Dependent Foam

Multistable architected material composed of curved beam unit has been widely studied for its promising energy dissipation/absorption applications. Although reusable and tailorable performance provided by these materials is gorgeous, one essential weakness of most of these materials is the rate independent energy dissipation/absorption capacity. In this work, we exploit a design strategy on strain rate dependent foam filled multi-stable architected composite material (SMACM). We attempt to introduce the strain-rate dependent behavior into SMACM by inducing strain rate dependent foam filling. Through numerical simulations and experimental tests, we characterize the mechanical behavior of SMACM and the effect of filled foam on it with specific geometric parameters. We first investigated the performance of foam filled curved beam unit cell, followed by planar array. The results indicate that the strength, stiffness, and snap through behavior of multistable structure can be influenced by the property of foam. Due to the strain-rate dependent property of filled foam, SMACM exhibit higher strength and adaptive energy dissipation ability at elevated loading rates. Furthermore, this method is showcased by introducing strain rate dependent foam into multistable structure, aimed to develop novel composite material with enhanced and customizable energy-dissipating properties. We envision that our study paves the way for challenging new applications, such as shock absorption and impact protection, etc.