ABSTRACT Elastic metamaterials with local resonance bandgaps are promising for low-frequency vibration mitigation. However, such locally resonant metamaterials inherently possess narrow bandgap width, and are usually achieved by multi-material structures, which are difficult to fabricate, limiting their potential in engineering practice. Here, we present a class of 3D single-phase elastic metamaterials exhibiting both locally resonant and Bragg scattering bandgaps. The local resonance of the single-material structure is achieved through the structural configuration rather than the combination of multiple materials. The bandgap property and effective mass density are investigated based on the numerical simulation and theoretical models. Furthermore, by constructing a graded system, the local resonance bandgap and Bragg scattering bandgap can be overlapped to form an ultra-wide vibration attenuation frequency range. The results are verified experimentally by a sample fabricated using additive manufacturing. This study suggests a feasible approach for realizing elastic metamaterials for engineering application.

中文翻译：

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用于低频和宽带减振的三维单相弹性超材料

摘要 具有局部共振带隙的弹性超材料有望用于降低低频振动。然而，这种局部共振超材料固有地具有窄带隙宽度，并且通常通过难以制造的多材料结构来实现，限制了它们在工程实践中的潜力。在这里，我们展示了一类具有局部共振和布拉格散射带隙的 3D 单相弹性超材料。单一材料结构的局部共振是通过结构配置而不是多种材料的组合来实现的。基于数值模拟和理论模型研究了带隙特性和有效质量密度。此外，通过构建分级系统，局部共振带隙和布拉格散射带隙可以重叠，形成超宽的振动衰减频率范围。结果通过使用增材制造制造的样品进行实验验证。该研究为实现工程应用的弹性超材料提出了一种可行的方法。