Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nonlinear mechanics of colloidal gels: creep, fatigue and shear-induced
  yielding   Colloidal gels are formed through the aggregation of attractive particles,
whose size ranges from 10~nm to a few micrometers, suspended in a liquid. Such
gels are ubiquitous in everyday life applications, from food products to paints
or construction materials, in particular thanks to their ability to easily
"yield", i.e., to turn from a solid to a liquid under the application of a weak
external load. Understanding and controlling the mechanical response of
colloidal gels is therefore of prime importance. Depending on the details of
the system, however, the resulting gel networks present different
microstructural organisations that may lead to widely different mechanical
responses. This raises important challenges in fully characterizing yielding
and in uncovering the mechanisms of nonlinear response in colloidal gels. In
this paper, we distinguish between two classes of colloidal gels showing
respectively reversible yielding, where the gel network reforms upon load
release, and irreversible yielding, where the network is fully destroyed
through fractures and phase separation. This broad, empirical distinction is
achieved through rheology and local experiments at a mesoscopic scale,
intermediate between the network characteristic size and the sample size. We
further discuss how the observables derived from creep and fatigue experiments
may be modelled to predict yielding and highlight open questions and future
research directions in the domain.

7
The categories of this paper are: hep-th
20
The categories of this paper are: acc-phys
28
The categories of this paper are: alg-geom
3
The categories of this paper are: physics
6
The categories of this paper are: astro-ph
19
The categories of this paper are: eess
13
The categories of this paper are: quant-ph
33
The categories of this paper are: plasm-ph
21
The categories of this paper are: adap-org
25
The categories of this paper are: patt-sol
1
The categories of this paper are: cs
14
The categories of this paper are: math-ph
31
The categories of this paper are: ao-sci
27
The categories of this paper are: comp-gas
8
The categories of this paper are: hep-ex
18
The categories of this paper are: econ