Huang Yan, Zhang Xiaozhe
School of Science, Xi'an Technological University, Xi'an 710021, People's Republic of China.
School of Materials Science and Engineering, Xi'an Polytechnic University, Xi'an 710048, People's Republic of China.
J Phys Condens Matter. 2021 Apr 23;33(18). doi: 10.1088/1361-648X/abeebd.
An effective method for realizing ultra-low-frequency single-mode band gap in pentamode metamaterials is proposed based on constituent materials. Results show that the decreasing ratio/(stiffness/mass density) of constituent material can significantly lower the frequency range of single-mode band gap. By merely replacing the constituent material from Al to rubber, the center frequencyof single-mode band gap can be reduced nearly 600 times (from 3621 Hz to 6.5 Hz), while the normalized bandwidth Δ/and the ratio of bulk modulusto shear modulusof pentamode structure keep substantially stable. The nonlinear fitting demonstrates that the relation betweenand/satisfies the logarithmic function. The two-component pentamode structure is designed to further explore the ultra-low-frequency single-mode band gap. The effects of thick-end diameterof double-cone, diameterand material type of additional sphere, on single-mode band gap of two-component system are analyzed. This work is attractive for several ∼Hz acoustic/elastic wave regulations using pentamode metamaterials.
基于组成材料，提出了一种在五模超材料中实现超低频单模带隙的有效方法。结果表明，组成材料的（刚度/质量密度）下降率可显著降低单模带隙的频率范围。仅将组成材料从铝替换为橡胶，单模带隙的中心频率可降低近600倍（从3621赫兹降至6.5赫兹），而五模结构的归一化带宽Δ/以及体积模量与剪切模量之比基本保持稳定。非线性拟合表明，与/之间的关系满足对数函数。设计了双组分五模结构以进一步探索超低频单模带隙。分析了双锥厚端直径、附加球体的直径和材料类型对双组分系统单模带隙的影响。这项工作对于使用五模超材料进行几赫兹的声/弹性波调控具有吸引力。
