A Design of Tunable Band Gaps in Anti-tetrachiral Structures Based on Shape Memory Alloy

Benefitted from the properties of band gaps, elastic metamaterials (EMs) have attracted extensive attention in vibration and noise reduction. However, the width and position of band gaps are fixed once the traditional structures are manufactured. It is difficult to adapt to complex and changeable service conditions. Therefore, research on intelligent tunable band gaps is of great importance and has become a hot issue in EMs. To achieve smart control of band gaps, a design of tunable band gaps in anti-tetrachiral structures based on shape memory alloy (SMA) is proposed in this paper. By governing the phase transition process of SMA, the geometric configuration and material properties of structures can be changed, resulting in tunable band gaps. Therein, the energy band structures and generation mechanism of tunable band gaps in different states are studied, realizing intelligent manipulation of elastic waves. In addition, the influence of different geometric parameters on band gaps is investigated, and the desired bandgap position can be customized, making bandgap control more flexible. In summary, the proposed SMA-based anti-tetrachiral metamaterial provides valuable reference for the application of SMA materials and the development of EMs.