【摘 要】
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A one-dimensional mechanical lattice system with local resonators is pro-posed as an elastic metamaterial model,which shows negative mass and negative modulus under specific frequency ranges.The proposed representative units,consisting of accu-rately arra
【机 构】
：
Shanghai Institute of Applied Mathematics and Mechanics,Shanghai Key Laboratory of Mechanics in Ener
论文部分内容阅读
A one-dimensional mechanical lattice system with local resonators is pro-posed as an elastic metamaterial model,which shows negative mass and negative modulus under specific frequency ranges.The proposed representative units,consisting of accu-rately arranged rigid components,can generate controllable translational resonance and achieve negative mass and negative modulus by adjusting the local structural parameters.A shape memory polymer is adopted as a spring component,whose Young\'s modulus is obviously affected by temperature,and the proposed metamaterials\' tunable ability is achieved by adjusting temperature.The effect of the shape memory polymer\'s stiffness variation on the band gaps is investigated detailedly,and the special phenomenon of inter-secting dispersion curves is discussed,which can be designed and controlled by adjusting temperature.The dispersion relationship of the continuum metamaterial model affected by temperature is obtained,which shows great tunable ability to manipulate wave prop-agation.
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