In traditional phononic metamaterials, elastic wave bandgaps are usually tuned by introducing periodic rigid inclusions in a soft matrix, but they are difficult to adapt to the changes of external mechanical environments. In this paper, inspired by the strategies of biological materials to achieve specific functions, we propose a kind of soft metamaterials with chiral and hierarchical structures. Their elastic wave bandgaps can be easily regulated in a larger space of frequency by means of the postbuckling-induced evolution of microstructures under loading. The postbuckling behavior of chiral hierarchical structures is investigated through finite element simulations and compared with those of symmetric hierarchical structures. The stress–strain curves, the phase diagram of uniaxial critical compressive strength, and the tunable elastic wave bandgaps of the proposed metamaterials are analyzed.

在传统的声子超材料中，通常通过在软基质中引入周期性的刚性夹杂物来调节弹性波带隙，但是它们很难适应外部机械环境的变化。在本文中，受生物材料实现特定功能的策略的启发，我们提出了一种具有手性和层次结构的软超材料。它们的弹性波带隙可以很容易地通过加载后屈曲引起的微观结构演变而在较大的频率范围内调节。通过有限元模拟研究了手性层次结构的后屈曲行为，并与对称层次结构进行了比较。应力-应变曲线，单轴临界抗压强度的相图，