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Plate-nanolattices at the theoretical limit of stiffness and strength.

ABSTRACT: Though beam-based lattices have dominated mechanical metamaterials for the past two decades, low structural efficiency limits their performance to fractions of the Hashin-Shtrikman and Suquet upper bounds, i.e. the theoretical stiffness and strength limits of any isotropic cellular topology, respectively. While plate-based designs are predicted to reach the upper bounds, experimental verification has remained elusive due to significant manufacturing challenges. Here, we present a new class of nanolattices, constructed from closed-cell plate-architectures. Carbon plate-nanolattices are fabricated via two-photon lithography and pyrolysis and shown to reach the Hashin-Shtrikman and Suquet upper bounds, via in situ mechanical compression, nano-computed tomography and micro-Raman spectroscopy. Demonstrating specific strengths surpassing those of bulk diamond and average performance improvements up to 639% over the best beam-nanolattices, this study provides detailed experimental evidence of plate architectures as a superior mechanical metamaterial topology.

SUBMITTER: Crook C

PROVIDER: S-EPMC7101344 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Plate-nanolattices at the theoretical limit of stiffness and strength.

Crook Cameron C Bauer Jens J Guell Izard Anna A Santos de Oliveira Cristine C Martins de Souza E Silva Juliana J Berger Jonathan B JB Valdevit Lorenzo L

Nature communications 20200327 1

Though beam-based lattices have dominated mechanical metamaterials for the past two decades, low structural efficiency limits their performance to fractions of the Hashin-Shtrikman and Suquet upper bounds, i.e. the theoretical stiffness and strength limits of any isotropic cellular topology, respectively. While plate-based designs are predicted to reach the upper bounds, experimental verification has remained elusive due to significant manufacturing challenges. Here, we present a new class of na ...[more]

PMID: 32221283

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Plate-nanolattices at the theoretical limit of stiffness and strength.

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Plate-nanolattices at the theoretical limit of stiffness and strength.

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