This study presents an evaluation of the mechanical behaviour of low porosity, ductile auxetic structures. Using time-averaged speckle interferometry and a specific experimental set-up, the eigenmodes and displacement fields of three low-porosity metallic auxetic samples were assessed and compared with the numerical simulations obtained using the commercial software Abaqus/Standard (Simulia Providence, RI). Guided by the finite element predictions, the eigenmode analysis was carried out by vibrating the specimens—each characterized by a different pore geometry—from 100 Hz to about 10 kHz analysing the structural response. A good agreement between the numerical calculations and the experimental results was found. This study not only validates the numerical-experimental approach used to analyse materials, but also to open a way to test and validate the performances of negative Poisson’s ratio structures and meta-materials in general applications. Furthermore, the findings of this work provides a new convincing and reliable experimental data, enlarge the knowledge about the elastic instabilities in metallic auxetic structures, supporting their use in critical applications.

Numerical and experimental eigenmode analysis of low porosity auxetic structures

FRANCESCONI, LUCA;BALDI, ANTONIO
2017

Abstract

This study presents an evaluation of the mechanical behaviour of low porosity, ductile auxetic structures. Using time-averaged speckle interferometry and a specific experimental set-up, the eigenmodes and displacement fields of three low-porosity metallic auxetic samples were assessed and compared with the numerical simulations obtained using the commercial software Abaqus/Standard (Simulia Providence, RI). Guided by the finite element predictions, the eigenmode analysis was carried out by vibrating the specimens—each characterized by a different pore geometry—from 100 Hz to about 10 kHz analysing the structural response. A good agreement between the numerical calculations and the experimental results was found. This study not only validates the numerical-experimental approach used to analyse materials, but also to open a way to test and validate the performances of negative Poisson’s ratio structures and meta-materials in general applications. Furthermore, the findings of this work provides a new convincing and reliable experimental data, enlarge the knowledge about the elastic instabilities in metallic auxetic structures, supporting their use in critical applications.
978-3-319-41600-7
Auxetic Material; Digital Image Correlation; Low Porosity, Negative Poisson’s ratio; Speckle Interferometry
File in questo prodotto:
File Dimensione Formato  
484_fra.pdf

Solo gestori archivio

Tipologia: versione pre-print
Dimensione 544.48 kB
Formato Adobe PDF
544.48 kB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/11584/182325
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 4
  • ???jsp.display-item.citation.isi??? 0
social impact