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Title: Metamaterial-like aerogels for broadband vibration mitigation
We report a mechanical metamaterial-like behavior as a function of the micro/nanostructure of otherwise chemically identical aliphatic polyurea aerogels. Transmissibility varies dramatically with frequency in these aerogels. Broadband vibration mitigation is provided at low frequencies (500–1000 Hz) through self-assembly of locally resonant metastructures wherein polyurea microspheres are embedded in a polyurea web-like network. A micromechanical constitutive model based on a discrete element method is established to explain the vibration mitigation mechanism. Simulations confirm the metamaterial-like behavior with a negative dynamic material stiffness for the micro-metastructured aerogels in a much wider frequency range than the majority of previously reported locally resonant metamaterials.
Authors:
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Award ID(s):
1661246
Publication Date:
NSF-PAR ID:
10291873
Journal Name:
Soft Matter
Volume:
17
Issue:
17
Page Range or eLocation-ID:
4496 to 4503
ISSN:
1744-683X
Sponsoring Org:
National Science Foundation
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