1. Introduction
To solve technical problems in modern highly organized technology, such as mechanical engineering,
robotics, medical technology, space technology, etc., materials with a set of fundamentally new
properties that could be controlled by external influences are required [1]. Magnetorheological
elastomers (MRE) the rheological and mechanical properties of which vary greatly under the influence
of an external magnetic field, attract great attention [2-3]. They consist of a non-magnetic polymer
medium in which magnetic particles are dispersed. The balance between magnetic and elastic forces
determine the resulting properties of the composites. This leads to numerous interesting effects that
manifest in such magnetically active composites. In addition to the magnetorheological effect a
magnetoelectro-rheological effect was also observed: a change in the viscoelastic properties of the
composite under the simultaneous action of external magnetic and electric fields arising from the
additional introduction of electroactive polymers into the material [4]. Significant magneto-
deformation and magnetostrictive phenomena in external inhomogeneous magnetic fields have been
established [5-7]. The phenomena of magnetic shape memory are discovered [8]. Magnetoresistive,
piezoresistive, and magneto-piezoresistive properties were determined [9-12]. Magnetodielectric,
magnetooptical, and magnetoacoustic effects were revealed [13–15]. Using the MRE dependence of
MIP: Engineering-2020
IOP Conf. Series: Materials Science and Engineering 862 (2020) 022062
IOP Publishing
doi:10.1088/1757-899X/862/2/022062
2
these elastic, rheological, electrical and other properties on the external magnetic field, magnetic and
electric field sensors, controlled damping devices, and shock absorbers of engineering products are
created [16-18]. However, many problems remain in the new generations effective MRE materials
development. Of great interest is the internal microstructure of magnetically active composites
changes that occur under such external influences [19]. In this work we further investigated the surface
structure of a similar magnetically active composites using scanning electron (SEM) and atomic force
(AFM) microscopy.
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Fe
nuclei hyperfine parameters of the carbonyl iron filler atoms in the
elastomeric matrix are determined using Mössbauer spectroscopy. The results obtained make it
possible better understand the observed unique effects characteristic of such magnetically active
composites.
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