Graphene-reinforced shape memorable chiral metamaterials: Theoretical analysis with experimental and numerical validations

The majority of the existing studies on chiral metamaterials have focused on the mechanism, fabrication and optimization of the structure-induced chirality, while the studies on the material perspective are scarce. Functional materials such as shape memory polymers (SMPs) open a promisingly emerging venue for improving the performance of chiral metamaterials from the material perspective. Here, the graphene-reinforced shape memorable chiral metamaterials (GR-SMCM) with self-adaptive thermomechanical response under thermal excitations are reported. Theoretical models are developed to consider the chiral metamaterials designed in the planar and tubular structures using the graphene-reinforced SMPs (GR-SMPs). The modified phase evolution-based constitutive model is expanded for the material influence of GR-SMPs, and the chiral compatibility is analyzed to examinate the structural influence of chiral metamaterials. Experiments and numerical simulations are conducted to validate the proposed theoretical models and great agreements are obtained. Parametric studies are carried out to investigate the tunability of the Young's modulus, Poisson's ratio, rotation angle of the hexagonal cells and temperature sensitivity. The reported GR-SMCM provide an efficacious approach to obtain self-adaptive performance with excellent controllability, which can be used to design advanced thermomechanical devices such as temperature sensing devices.(c) 2023 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Automated summary

The majority of previous studies on chiral metamaterials focused on the mechanism, fabrication, and optimization of structure-induced chirality, with limited attention on the material perspective. This research introduces graphene-reinforced shape memory chiral metamaterials that exhibit self-adaptive thermomechanical response under thermal excitations. Theoretical models were developed to design the chiral metamaterials with planar and tubular structures using graphene-reinforced shape memory polymers, and experiments and simulations were conducted to validate the proposed models.