A novel hybrid bistable auxetic metamaterials with reusable geometric configuration for energy dissipation

Purpose ReEntrant Honeycomb, characterized by its superior mechanical properties with energy absorption characteristics and tunability, presents promising applications for protective structures offering better stability. However, conventional designs fall short in terms of the reusability of these metamaterials. This study aims to investigate the impact of buckling strip configuration on energy absorption utilizing topological features instead of inelastic deformation, addressing a critical gap in the reusability of such materials. The research seeks new insights into modes of dissipation energy, contributing to a deeper understanding of the integrity of hybrid metamaterials. Design/methodology/approach A novel ReEntrant auxetic unit featuring a tunable bistable snap-through mechanism is proposed. After investigating three polymer types, the specimens are 3D printed for material characterization. The force deformation and energy dissipation correlations are attempted with a finite element-based numerical investigation approach. Findings The effect of simultaneous control for topological details was identified quantitatively in terms of components of the total energy absorbed and/or dissipated. The proposed re-entrant structures with optimized strip thickness and ReEntrant angle exhibited reasonably better energy dissipation because of the additional snapping energy. Originality/value Traditional ReEntrant honeycomb dissipates energy imparted primarily by inelastic deformation. Here, the bistable snap-through mechanism in the present novel hybrid design is focused upon and is computationally investigated for minimal yielding. Hence, the shape is regained during elastic recovery only (without additional load). Such recovery, in turn, ensures the re-usability and post-deformation integrity of the designed unit.