Metal-based foam-filling low-frequency broad-band-gap elastic metamaterial

Abstract

The invention relates to a metal-based foam-filling low-frequency broad-band-gap elastic metamaterial. The elastic metamaterial adopts a metal material as a matrix sheet material. Multiple round holes are arranged in the matrix sheet material in an array manner. Each round hole is filled with a foamed aluminium material to form a filling unit. Each filling unit is adhered to a local resonance unit. Each local resonance unit comprises two pairs of cylinders which are symmetrically arranged at two edges of the filling unit and are on the same straight line with the center of circle and the filling unit. The elastic metamaterial meets requirements for structural intensity and rigidity. A theoretical model of a prepared test piece has three complete band gaps in a low frequency range of below 500Hz and has a curved vibration band gap with the width of 400Hz. The lower boundary of the band gap is 66Hz. The metamaterial can be used for achieving low frequency broadband vibration noise control of a naval ship structure, and is significant for application of the elastic metamaterial in engineering vibration damping and noise reduction and naval ship acoustic stealth.

Description

technical field [0001] The invention relates to the technical field of elastic metamaterials, in particular to a metal-based foam-filled elastic metamaterial with low frequency and wide bandgap. Background technique [0002] The continuous progress of science and technology and the rapid development of social economy have brought new challenges to people. On the one hand, with the acceleration of industrialization and urbanization, urban industrial noise and traffic noise pollution problems are becoming increasingly serious. The ubiquity of noise not only affects people's normal rest and work, but also easily damages the hearing system, nervous system, and even induces cardiovascular and cerebrovascular diseases or mental diseases. Therefore, it is undoubtedly of great social and economic significance to explore new vibration and noise reduction materials and to study more effective noise reduction and noise reduction technologies. [0003] On the other hand, in the field ...

AI Technical Summary

Problems solved by technology

[0005] Although elastic metamaterials have great potential application prospects, due to the fact that it took less than 20 years from the conception to the development of the theoretical system, the existing elastic metamaterials are generally formed by soft material matrix coated with hard material scatterers. The mechanical strength is not high enough, and the mechanical components and equipment in engineering practice are generally composed of metal substrates

In addition, the filling materials of elastic metamaterials are generally isotropic and uniform materials such as silicone rubber materials, which have poor strength and stiffness.

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