246 / 2021-04-14 17:09:52

Low frequency vibration attenuation of arrowheads metamaterials sandwich plate with negative Poisson’s ratio core

arrowheads metamaterials, bandgap structure, sandwich plate, negative Poisson’s ratio

Acoustic metamaterials and absorbing materials

Abstract: Recent researches in periodic structures, phononic crystal and metamaterials which present special bandgap or stopbands, in which the propagation suppression of elastic waves is originated from Bragg scattering or local resonance mechanisms. The conventional sandwich plates are designed without significant bandgap structure, since the conventional sandwich plate structure does not have the performance of noise control and vibration isolation in a wide range of frequency bands. This work proposes a new type of low frequency bandgap metamaterials core sandwich plate (MCSP) with negative Poisson's ratio sandwich layer, and investigates the acoustic bandgap characteristics of the MCSPs, where the frequency bands are easily adjustable by changing the lattice structure parameters and materials spatial distribution. In the present work, arrowheads metamaterial sandwich plate not only present strong bending resistance but also ultra-wide vibration attenuation in stopband ranges. The bandgap frequencies, vibration reduction efficiency and mechanical properties (the Poisson's ratio, equivalent elastic modulus and bending strength) of arrowheads lattice metamaterials can be tailored through configuration parameters, arrowhead arrangements, and materials space distributions. The vibration transmissions and flexural properties of the sandwich metamaterials plate were investigated using numerical calculation, finite element simulation, and experiments. The MCSPs was tested by experimental method for vibration frequency response and bending property and verified vibrations attenuation with elastic waves blocking propagation behavior in the stopband frequency interval of the metamaterial lattice. The MCSPs possess a wide range of potential applications in vibration isolation, noise suppression and bending resistance for spacecraft structure, ship plate and shell structure, rail transportation equipment, etc.