https://doi.org/10.1051/epjconf/202125001033
A novel apparatus and methodology for the high frequency mechanical characterisation of ultrasoft materials
Department of Engineering Science, University of Oxford, Parks Road, Oxford, OX1 3PJ, UK
* Corresponding author: aaron.graham@eng.ox.ac.uk
Published online: 9 September 2021
Characterising the mechanical response of ultra-soft materials is challenging, particularly at high strain rates and frequencies [1]. Time Temperature Superposition (TTS) can sometimes be used to mitigate these limitations [2], however not all materials are suitable for TTS. Biological tissues are particularly difficult to test: in addition to the extreme softness, challenges arise due to specimen inhomogeneity, sensitivity to boundary conditions, natural biological variability, and complex post-mortem changes. In the current study, a novel experimental apparatus and methodology was developed and validated using low modulus silicone elastomers as model materials. The full field visco-elastic shear response was characterised over a wide range of deformation frequencies (100-1000+ Hz) and amplitudes using Digital Image Correlation (DIC) and the Virtual Fields Method (VFM). This methodology allows for the extraction of fullfield material properties that would be difficult or impossible to obtain using traditional engineering techniques.
© The Authors, published by EDP Sciences, 2021
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.