A quasi-zero-stiffness elastic metamaterial for energy absorption and shock attenuation

A multi-step quasi-zero-stiffness metamaterial (MS-QZSM) is proposed, which exhibits potential applications in various engineering scenarios, such as multi-vibration mitigation and mechanical protection. At the level of the cell, the MS-QZSM is characterized by the elastic ring connected in parallel with two cross-curved beams respectively, which exhibits multiple deformation behaviors and quasi-zero-stiffness phases (force plateaus) under global compression load. Whithin the line elastic range of material, the proposed metamaterial can achieve QZS region. The multi-step QZS features of the MS-QZSM are theoretically analyzed, and validated by experi-ments and numerical calculations. Furtherly, the MS-QZSM performances of multiple deformation behavior and energy absorption are investigated by loading-unloading compressive experiments and simulations. Experiment results are in agreement with the simulation results, which show that there are two force plateaus and an obvious hysteretic loop. MS-QZSM has no structural damage during deformation, but plastic deformation occurs. In the area of multi-vibration mitigation and mechanical protection, the findings of this study can expand application prospects of metamaterial in engineering structures.