Smart Materials and Structures,
Год журнала:
2022,
Номер
31(6), С. 065018 - 065018
Опубликована: Апрель 29, 2022
Abstract
Magnetorheological
elastomers
(MREs)
mechanically
respond
to
external
magnetic
stimuli
by
changing
their
mechanical
properties
and/or
shape.
Recent
studies
have
shown
the
great
potential
of
MREs
when
manufactured
with
an
extremely
soft
matrix
and
soft-magnetic
particles.
Under
application
field,
such
present
significant
stiffening,
field
is
off,
they
show
a
softer
response,
being
these
alternative
states
fully
reversible.
Although
particles
are
suitable
for
high
susceptibility,
require
actuation
remain
constant
in
order
achieve
magneto-mechanical
stiffening.
Here,
we
solution
based
on
hard-magnetic
provide
stiffening
responses
that
can
be
sustained
along
time
without
need
keeping
on.
To
this
end,
manufacture
novel
(stiffness
1
kPa)
characterise
them
under
shear
confined
expansion
deformation
modes,
providing
comparison
framework
counterparts.
The
nature
allows
easily
activating
couplings
actuation.
In
regard,
approach
setting
below
saturating
field.
addition,
free
tests
hints
microstructural
transmission
torques
from
viscoelastic
matrix,
resulting
macroscopic
geometrical
effects
intricate
shape-morphing
phenomena.
npj Computational Materials,
Год журнала:
2022,
Номер
8(1)
Опубликована: Июль 28, 2022
Abstract
Recent
advances
in
magnetorheological
elastomers
(MREs)
have
posed
the
question
on
whether
combination
of
both
soft-
and
hard-magnetic
particles
may
open
new
routes
to
design
versatile
multifunctional
actuators.
Here,
we
conceptualise
ultra-soft
hybrid
MREs
(≈1–10
kPa
stiffness)
combining
experimental
computational
approaches.
First,
a
comprehensive
characterisation
is
performed.
The
results
unravel
that
magneto-mechanical
performance
can
be
optimised
by
selecting
an
adequate
mixing
ratio
between
particles.
Then,
multi-physics
framework
provides
insights
into
synergistic
interactions
at
microscale.
Soft
amplify
magnetisation
hard
contribute
torsional
actuation.
Our
numerical
suggest
effective
response
emerges
from
these
intricate
interactions.
Overall,
uncover
exciting
possibilities
push
frontiers
MRE
solutions.
These
are
demonstrated
simulating
bimorph
beam
actuation
flexibility
either
enhancing
mechanical
bending
or
material
stiffening,
depending
magnetic
stimulation.
SLAS TECHNOLOGY,
Год журнала:
2023,
Номер
28(3), С. 127 - 141
Опубликована: Фев. 17, 2023
Cancer
is
a
critical
cause
of
global
human
death.
Not
only
are
complex
approaches
to
cancer
prognosis,
accurate
diagnosis,
and
efficient
therapeutics
concerned,
but
post-treatments
like
postsurgical
or
chemotherapeutical
effects
also
followed
up.
The
four-dimensional
(4D)
printing
technique
has
gained
attention
for
its
potential
applications
in
therapeutics.
It
the
next
generation
three-dimensional
(3D)
technique,
which
facilitates
advanced
fabrication
dynamic
constructs
programmable
shapes,
controllable
locomotion,
on-demand
functions.
As
well-known,
it
still
initial
stage
requires
insight
study
4D
printing.
Herein,
we
present
first
effort
report
on
technology
This
review
will
illustrate
mechanisms
used
induce
management.
recent
be
further
detailed,
future
perspectives
conclusions
finally
proposed.
Journal of the Mechanics and Physics of Solids,
Год журнала:
2023,
Номер
173, С. 105232 - 105232
Опубликована: Фев. 2, 2023
Pre-existing
flaws
in
highly
stretchable
elastomers
trigger
fracture
under
large
deformations.
For
multifunctional
materials,
mechanics
may
be
influenced
by
additional
physical
phenomena.
This
work
studies
the
implications
of
hard
magnetics
on
behaviour
ultra-soft
magnetorheological
(MREs).
We
experimentally
demonstrate
that
MREs
with
remanent
magnetisation
have
up
to
a
50%
higher
toughness
than
non
pre-magnetised
samples.
Moreover,
we
report
crack
closure
due
magnetic
field
as
mechanism
delays
opening
cracks
MREs.
To
overcome
experimental
limitations
and
provide
further
understanding,
phase-field
model
for
is
conceptualised.
The
numerical
incorporates
magneto-mechanical
coupling
stress
concentration
at
tip
smaller
when
MRE
pre-magnetised.
Overall,
this
unveils
intriguing
applications
functional
actuators,
better
potential
performance
cyclic
loading.
Advanced Engineering Materials,
Год журнала:
2023,
Номер
25(16)
Опубликована: Май 11, 2023
The
magnetorheological
elastomers
(MREs)
are
novel
multifunctional
materials
wherein
their
viscoelastic
properties
can
be
varied
instantly
under
an
application
of
applied
magnetic
field.
Due
to
field‐dependent
stiffness
and
damping
properties,
MREs
widely
used
in
the
development
design
MRE‐based
adaptive
vibration
isolators
absorbers
also
biomedical
engineering.
Moreover,
due
inherent
magnetostriction
effect
have
enormous
potential
for
soft
actuators.
dynamic
behavior
is
affected
by
various
material
parameters
(e.g.,
matrix
particle
types,
concentration,
additives)
as
well
mechanical
loading
frequency,
amplitude,
temperature,
flux
density).
Understanding
predicting
on
response
paramount
importance
structures
systems.
This
review
paper
mainly
aims
provide
a
comprehensive
study
constitutive
models
predict
nonlinear
magnetomechanical
MREs.
Particular
emphasis
paid
physics‐based
including
continuum‐
microstructure‐based
models.
phenomenological
describing
magnetoviscoelastic
temperature
such
properly
addressed.
International Journal of Applied Mechanics,
Год журнала:
2024,
Номер
16(06)
Опубликована: Фев. 3, 2024
Hydrogels
can
change
their
size
upon
swelling.
The
swelling
ratio
is
the
same
for
all
directions
in
stress-free
state.
Dielectric
elastomers
reduce
thickness
and
expand
area
an
electric
field.
Similarly,
expansion
plane
also
different
directions.
This
isotropic
shape
effect
limits
function
of
these
soft
materials
certain
circumstances.
To
address
this
issue,
recent
works
have
shown
that
incorporation
fibers
into
polymer
matrix
induce
anisotropic
response
external
stimulus.
In
work,
we
develop
multi-field
coupling
models
both
fiber-reinforced
hydrogels
dielectric
elastomers.
For
former,
free
energy
caused
by
stretching
chains
mixing
solvents
networks.
Fickian-type
law
adopted
solvent
diffusion.
density
latter
consists
a
mechanical
part,
considering
deformation
fibers,
polarization
component.
Gauss’s
to
obtain
distribution
are
then
implemented
finite
element
analysis.
We
consider
stimulus-responsiveness
bilayer
strips
with
active
layer
passive
layer.
Without
bend
contrast,
changes
helix
shapes,
which
be
further
tuned
changing
fibers.
work
provides
efficient
design
tool
self-folding
structures
based
on
stimulus-responsive
polymers.
