TY - JOUR

T1 - The emergence of sequential buckling in reconfigurable hexagonal networks embedded into soft matrix

AU - Galich, Pavel I.

AU - Sharipova, Aliya

AU - Slesarenko, Slava

N1 - Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. Copyright: Copyright 2021 Elsevier B.V., All rights reserved.

PY - 2021/4/18

Y1 - 2021/4/18

N2 - The extreme and unconventional properties of mechanical metamaterials originate in their sophisticated internal architectures. Traditionally, the architecture of mechanical metamaterials is decided on in the design stage and cannot be altered after fabrication. However, the phenomenon of elastic instability, usually accompanied by a reconfiguration in periodic lattices, can be harnessed to alter their mechanical properties. Here, we study the behavior of mechanical metamaterials consisting of hexagonal networks embedded into a soft matrix. Using finite element analysis, we reveal that under specific conditions, such metamaterials can undergo sequential buckling at two different strain levels. While the first reconfiguration keeps the periodicity of the metamaterial intact, the secondary buckling is accompanied by the change in the global periodicity and formation of a new periodic unit cell. We reveal that the critical strains for the first and the second buckling depend on the metamaterial geometry and the ratio between elastic moduli. Moreover, we demonstrate that the buckling behavior can be further controlled by the placement of the rigid circular inclusions in the rotation centers of order 6. The observed sequential buckling in bulk metamaterials can provide additional routes to program their mechanical behavior and control the propagation of elastic waves.

AB - The extreme and unconventional properties of mechanical metamaterials originate in their sophisticated internal architectures. Traditionally, the architecture of mechanical metamaterials is decided on in the design stage and cannot be altered after fabrication. However, the phenomenon of elastic instability, usually accompanied by a reconfiguration in periodic lattices, can be harnessed to alter their mechanical properties. Here, we study the behavior of mechanical metamaterials consisting of hexagonal networks embedded into a soft matrix. Using finite element analysis, we reveal that under specific conditions, such metamaterials can undergo sequential buckling at two different strain levels. While the first reconfiguration keeps the periodicity of the metamaterial intact, the secondary buckling is accompanied by the change in the global periodicity and formation of a new periodic unit cell. We reveal that the critical strains for the first and the second buckling depend on the metamaterial geometry and the ratio between elastic moduli. Moreover, we demonstrate that the buckling behavior can be further controlled by the placement of the rigid circular inclusions in the rotation centers of order 6. The observed sequential buckling in bulk metamaterials can provide additional routes to program their mechanical behavior and control the propagation of elastic waves.

KW - Buckling

KW - Elastic wave propagation

KW - Instabilities

KW - Mechanical metamaterials

KW - Reconfiguration

KW - Sequential buckling

KW - DESIGN

KW - buckling

KW - INDUCED PATTERN TRANSFORMATION

KW - sequential buckling

KW - reconfiguration

KW - ELLIPTICITY

KW - COMPOSITES

KW - elastic wave propagation

KW - METAMATERIALS

KW - instabilities

KW - INSTABILITIES

KW - ELASTIC-WAVE PROPAGATION

KW - mechanical metamaterials

KW - LATTICE STRUCTURES

UR - http://www.scopus.com/inward/record.url?scp=85104955221&partnerID=8YFLogxK

U2 - 10.3390/ma14082038

DO - 10.3390/ma14082038

M3 - Article

AN - SCOPUS:85104955221

VL - 14

JO - Materials

JF - Materials

SN - 1996-1944

IS - 8

M1 - 2038

ER -