The development of the current technology has increased the requirement for the versatility of acoustic metamaterials. In this study, the band gap (BG) tuning of the stretch-dominated thermal expansion lattice metamaterials with different configurations composed of triangular units is studied using the finite element method, and a design method for metamaterials tuned by external temperature changes in multiple frequency ranges is proposed. The results indicate that the stretch-dominated thermal expansion material can maintain the original customized thermal expansion performance while possessing the characteristics of the BG in addition to realizing different degrees of BG tunability when the temperature changes. The results provide a theoretical basis for attaining the thermal expansion/tunable BG dual-objectives design. The objective is to achieve the dual goals of tailorable coefficient of thermal expansion and tunable BG design through reasonable material selection and shape optimization.

当前技术的发展增加了对声学超材料的多功能性的需求。在这项研究中，使用有限元方法研究了由三角形单元组成的具有不同构型的拉伸支配热膨胀晶格超材料的带隙（BG）调谐，并设计了一种通过多种频率范围内的外部温度变化来调谐超材料的设计方法被提议。结果表明，以拉伸为主的热膨胀材料除了在温度变化时实现不同程度的BG可调性外，还可以保持原始的定制热膨胀性能，同时具有BG的特性。研究结果为实现热膨胀/可调BG双目标设计提供了理论依据。