Basic magnetic properties of magnetoactive elastomers of mixed content

Autor: Becker, T. I., Stolbov, O. V., Borin, D. Y., Zimmermann, K., Raikher, Y. L.
Jazyk: angličtina
Rok vydání: 2020
Předmět:
Materials science
Field (physics)
MAGNETIC PARAMETERS
02 engineering and technology
ELASTOMERS
01 natural sciences
FILLERS
PLASTICS
Magnetization
Phase (matter)
0103 physical sciences
HOMOGENEOUS DISTRIBUTION
MESOSCOPIC MODELING
General Materials Science
SUPERCONDUCTING MATERIALS
Electrical and Electronic Engineering
MAGNETIC BUBBLES
MAGNETOSTATICS
MAGNETIC AND MECHANICAL PROPERTIES
Civil and Structural Engineering
010302 applied physics
Mesoscopic physics
Condensed matter physics
Magnetic moment
MAGNETIZATION
021001 nanoscience & nanotechnology
Condensed Matter Physics
Magnetostatics
MUTUAL DISPLACEMENT
Magnetic susceptibility
Atomic and Molecular Physics
and Optics

Magnetic field
MAGNETIC INTERACTIONS
MAGNETIC MOMENTS
Mechanics of Materials
Signal Processing
STRONG MAGNETIC FIELDS
EXPERIMENTAL INVESTIGATIONS
0210 nano-technology
MAGNETIC SUSCEPTIBILITY
Zdroj: Smart Materials and Structures
Popis: The results of theoretical and experimental investigations of the polymer composites that belong to a class of magnetoactive elastomers with mixed magnetic content (MAEs-MC) are presented. The fundamental distinction of such composites from ordinary magnetoactive elastomers is that the magnetic filler of MAEs-MC comprises both magnetically soft (MS) particles of size 3–5 µm and magnetically hard (MH) particles whose size is an order of magnitude greater. Since MH particles of the magnetic filler are mixed into a composition in a non-magnetised state, this can ensure preparation of samples with fairly homogeneous distribution of the filler. The ‘initiation’ process of a synthesised MAE-MC is done by its magnetisation in a strong magnetic field that imparts to the sample unique magnetic and mechanical properties. In this work, it is shown that the presence of MS particles around larger MH particles, firstly, causes an augmentation of magnetic moments, which the MH particles acquire during initiation, and secondly, enhances the magnetic susceptibility and remanent magnetisation of MAEs-MC. These magnetic parameters are evaluated on the basis of the macroscopic magnetostatics from the experimental data of spatial scanning of the field over the space around MAEs-MC made in the shape of a spheroid. A set of samples with a fixed MH and varying MS volume contents that are initiated in two different fields, is used. The developed mesoscopic model of magnetic interactions between the MH and MS phases is able to explain the experimentally observed dependencies of the magnetic parameters on the concentration of the MS phase. The problem is solved numerically under the assumption that the elastic matrix of MAEs-MC is rigid, i.e. the mutual displacements of the particles are negligible. The model helps to elucidate the interaction of the magnetic phases and to establish that the MS phase plays thereby a dual role. On the one hand, the MS phase screens out the field acting inside MH particles, and on the other hand, it forms mesoscopic magnetic bridges between adjoining MH particles, which in turn enhance their field. The combined interplay of these contributions defines the resulting material properties of MAEs-MC on the macroscopic scale.
Databáze: OpenAIRE