Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Probing local nonlinear viscoelastic properties in soft materials   Minimally invasive experimental methods that can measure local rate dependent
mechanical properties are essential in understanding the behaviour of soft and
biological materials in a wide range of applications. Needle based measurement
techniques such as Cavitation Rheology and Volume Controlled Cavity Expansion
(VCCE), allow for minimally invasive local mechanical testing, but have been
limited to measuring the elastic material properties. Here, we propose several
enhancements to the VCCE technique to adapt it for characterization of
viscoelastic response at low to medium stretch rates ($10^{-2}$ - $1$
s${}^{-1}$). The proposed technique performs several cycles of
expansion-relaxation at controlled stretch rates in a cavity expansion setting
and then employs a large deformation viscoelastic model to capture the measured
material response. Application of the technique to soft PDMS rubber reveals
significant rate dependent material response with high precision and
repeatability, while isolating equilibrated states that are used to directly
infer the quasistatic elastic modulus. The technique is further established by
demonstrating its ability to capture changes in the rate dependent material
response of a tuneable PDMS system. The measured viscoelastic properties are
used to explain earlier reports of rate insensitive material response by needle
based methods: it is demonstrated that the conventional use of constant
volumetric rate cavity expansion can induce high stretch rates that lead to
viscoelastic stiffening and an illusion of rate insensitive material response.
We thus conclude with a cautionary note on possible overestimation of the
quasistatic elastic modulus in previous studies and suggest that the stretch
rate controlled expansion protocol, proposed in this work, is essential for
accurate estimation of both quasistatic and dynamic material parameters.

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The categories of this paper are: hep-ph
12
The categories of this paper are: nucl-th
37
The categories of this paper are: supr-con
25
The categories of this paper are: patt-sol
1
The categories of this paper are: cs
9
The categories of this paper are: nlin
17
The categories of this paper are: q-fin
19
The categories of this paper are: eess
20
The categories of this paper are: acc-phys
15
The categories of this paper are: nucl-ex
36
The categories of this paper are: cmp-lg
30
The categories of this paper are: q-alg
10
The categories of this paper are: q-bio
32
The categories of this paper are: atom-ph
13
The categories of this paper are: quant-ph
3
The categories of this paper are: physics