Journal Description
Magnetism
Magnetism
is an international, peer-reviewed, open access journal on science and technology for all original researches on magnetism and related fields, published quarterly online by MDPI.
- Open Access—free to download, share, and reuse content. Authors receive recognition for their contribution when the paper is reused.
- Rapid Publication: first decisions in 15 days; acceptance to publication in 3 days (median values for MDPI journals in the second half of 2021).
- Recognition of Reviewers: APC discount vouchers, optional signed peer review, and reviewer names published annually in the journal.
- Magnetism is a companion journal of Electronics.
Latest Articles
Competing Magnetic Interactions in Inverted Zn-Ferrite Thin Films
Magnetism 2022, 2(2), 168-178; https://doi.org/10.3390/magnetism2020012 - 17 May 2022
Abstract
Zn-ferrite is a versatile material among spinels owing to its physicochemical properties, as demonstrated in rich phase diagrams, with several conductive or magnetic behaviors dictated by its cation inversion. The strength and the type of cation inversion can be manipulated through the various
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Zn-ferrite is a versatile material among spinels owing to its physicochemical properties, as demonstrated in rich phase diagrams, with several conductive or magnetic behaviors dictated by its cation inversion. The strength and the type of cation inversion can be manipulated through the various thermal treatment conditions. In this study, inverted Zn-ferrite thin films prepared from radio frequency magnetron sputtering were subjected to different in situ (in vacuum) and ex situ (in air) annealing treatments. The temperature and field dependence of magnetization behaviors reveal multiple magnetic interactions compared to its bulk antiferromagnet behavior. Using the magnetic component model, the different magnetic interactions can be explained in terms of superparamagnetic (SPM), paramagnetic (PM), and ferrimagnetic (FM) contributions. At low temperatures, the SPM and FM contributions can be approximated to the hard and soft ferrimagnetic phases of Zn-ferrite, respectively, which changes with the annealing temperature and sputter power. Distinct magnetic properties emanating from in situ annealing compared to the ex situ annealing were ascribed to the nonzero Fe2+/Fe3+ ratio, leading to the different magnetic interactions. The anisotropy was found to be the key parameter that governs the behavior of annealed in situ samples.
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(This article belongs to the Special Issue Magnetic Surfaces: Thin Films and Nanostructures)
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Anthropogenic Sources of Electromagnetic Interference in the Lowest ELF Band Recordings (Schumann Resonances)
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, , , , , and
Magnetism 2022, 2(2), 152-167; https://doi.org/10.3390/magnetism2020011 - 05 May 2022
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Recording systems that deal with Extra Low Frequency (ELF) data in the Schumann resonance (SR) range exhibit high sensitivity to external noise. In our effort to refine a time series by identifying and removing external disturbances from real data, we analyzed the effect
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Recording systems that deal with Extra Low Frequency (ELF) data in the Schumann resonance (SR) range exhibit high sensitivity to external noise. In our effort to refine a time series by identifying and removing external disturbances from real data, we analyzed the effect of induced deliberate anthropogenic disturbances. The signals were recorded at the same time and same place by two separate systems with different designs and implementations. The main purpose of this experiment was to confirm that different systems in various observational sites could identify parasitic noises in the same way. The outcomes of this study may help ELF observers to discern intrinsic signals from artificial noise.
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Vector-Based Magnetic Circuit Modelling of Induction Motors
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Magnetism 2022, 2(2), 130-151; https://doi.org/10.3390/magnetism2020010 - 28 Apr 2022
Abstract
Electro-mechanical devices incorporating rotating magnetic fields can be modelled using a wide range of analytical techniques. Choosing a modelling technique usually requires a trade off between computational efficiency and accuracy. Magnetic flux-based models aim to achieve an optimum balance between computational intensity and
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Electro-mechanical devices incorporating rotating magnetic fields can be modelled using a wide range of analytical techniques. Choosing a modelling technique usually requires a trade off between computational efficiency and accuracy. Magnetic flux-based models aim to achieve an optimum balance between computational intensity and accuracy, as required for real time control applications. This paper demonstrates how vector-based magnetic circuit equations can be used to describe the operational characteristics of an induction motor at a more fundamental level than commonly used magnetic flux models. Doing so allows for closed form equations to be derived directly from device-specific geometry. The resultant model has advantages of numerical method-based analytical techniques while retaining the computational efficiency of closed form equations.
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(This article belongs to the Special Issue Mathematical Modelling and Physical Applications of Magnetic Systems)
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Reflection and Refraction of a Spin at the Edge of a Quasi-Two-Dimensional Semiconductor Layer (Quantum Well) and a Topological Insulator
Magnetism 2022, 2(2), 117-129; https://doi.org/10.3390/magnetism2020009 - 18 Apr 2022
Abstract
We derive the reflection and refraction laws for an electron spin incident from a quasi-two-dimensional semiconductor region (with no spin–orbit interaction) on the metallic surface of a topological insulator (TI) when the two media are in contact edge to edge. For a given
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We derive the reflection and refraction laws for an electron spin incident from a quasi-two-dimensional semiconductor region (with no spin–orbit interaction) on the metallic surface of a topological insulator (TI) when the two media are in contact edge to edge. For a given incident angle, there can generally be two different refraction angles for refraction into the two spin eigenstates in the TI surface, resulting in two different ‘spin refractive indices’ (birefringence) and the possibility of two different critical angles for total internal reflection. We derive expressions for the spin refractive indices and the critical angles, which depend on the incident electron’s energy for given effective masses in the two regions and a given potential discontinuity at the TI/semiconductor interface. For some incident electron energies, there is only one critical angle, in which case 100% spin polarized injection can occur into the TI surface from the semiconductor if the angle of incidence exceeds that critical angle. The amplitudes of reflection of the incident spin with and without spin flip at the interface, as well as the refraction (transmission) amplitudes into the two spin eigenstates in the TI, are derived as functions of the angle of incidence.
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(This article belongs to the Special Issue Exclusive Collection: Papers from the Editorial Board Members of Magnetism)
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Static and Dynamic Magneto-Elastic Sensing Properties of Fe-Al Alloy Powder-Epoxy Composite Patches
Magnetism 2022, 2(2), 105-116; https://doi.org/10.3390/magnetism2020008 - 01 Apr 2022
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By combining the two types of magnetoelastic and magnetochromatic materials in an epoxy, we can make a hybrid system that exhibits an optical response due to an elastic strain. It could be used in structural health monitoring, for real-time monitoring of crack propagation
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By combining the two types of magnetoelastic and magnetochromatic materials in an epoxy, we can make a hybrid system that exhibits an optical response due to an elastic strain. It could be used in structural health monitoring, for real-time monitoring of crack propagation or general evaluation of the condition of a structure, both visualized by a change in color. In this study, magnetostrictive polymer composites (MPCs) with Fe81Al19 (Alfenol) alloy particles are evaluated to determine magneto-elastic properties in composite patches attached to a surface, prior to understanding the full hybrid magneto–elasto–optical interactions. To measure static magneto-elastic performance, a tension apparatus within a solenoid was fabricated to apply uniform strain to the MPC patch on an aluminum dog-bone substrate. It was demonstrated that, for epoxies with an elastic modulus higher than ~0.1 GPa, a tensile strain/stress applied to the composite improved magneto-elastic coupling, resulting in increased permeability values, at least up to strains of 0.1%. Composites were fabricated with both spherical and flake-shaped powders, with flake-shaped powders exhibiting better magnetic responses than those with spherical morphology. Alfenol MPCs were also measured dynamically at ultrasonic frequencies, exhibiting comparable dynamic sensing performance to Galfenol at 120 kHz using ultrasonic guided wave techniques.
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Orientation-Dependent Indentation Behaviour of Additively Manufactured FeCo Sample: A Quasi In-Situ Study
Magnetism 2022, 2(2), 88-104; https://doi.org/10.3390/magnetism2020007 - 25 Mar 2022
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The quasi in-situ indentation behaviour of <110>||BD and <111>||BD-oriented grains in a FeCo alloy is studied in this investigation. The effect of build height on melt pool shape and melt pool size is also studied by finite element method simulations. As the building
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The quasi in-situ indentation behaviour of <110>||BD and <111>||BD-oriented grains in a FeCo alloy is studied in this investigation. The effect of build height on melt pool shape and melt pool size is also studied by finite element method simulations. As the building height increases, the aspect ratio of the elliptical melt pool increases. Correspondingly, the effect of the laser scan speed on the melt pool shape and size is studied by the finite element method, because, as the laser scan speed increases, the aspect ratio of the elliptical melt pool increases, too. The microstructural characterisation of the indentation area before and after indentation is performed by electron backscatter diffraction (EBSD). Based on the EBSD data grain reference orientation deviation (GROD), calculations are performed to describe the effect of indentations on the neighbouring grain orientations. High GROD angles are detected in the neighbouring grain region adjoining the indented grain. An in-depth slip trace analysis shows the activation of all three slip systems ({110}<111>, {112}<111> and {123}<111>) which is also confirmed by slip lines on the sample surface that are detected by laser scanning confocal microscopy. A high concentration of geometrically necessary dislocations (GNDs) are observed on the adjoining area to the indentation. Local surface topography measurements by laser scanning confocal microscopy confirmed the formation of pile-ups near the indentation.
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The Relativistic Electrodynamics of Classical Charged Particles
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Magnetism 2022, 2(1), 74-87; https://doi.org/10.3390/magnetism2010006 - 18 Mar 2022
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Maxwell’s equations and the Lorentz force equation form the foundation of classical electromagnetic theory and their discovery led to the development of special relativity. Despite this achievement, their universal compatibility with the conservation of momentum and relativistic energy transformations is still debated. Incorporating
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Maxwell’s equations and the Lorentz force equation form the foundation of classical electromagnetic theory and their discovery led to the development of special relativity. Despite this achievement, their universal compatibility with the conservation of momentum and relativistic energy transformations is still debated. Incorporating effects of hidden momentum with the Lorentz force equation or using the Einstein–Laub formula are two common approaches to address some of these concerns. Which method to use, or if a change to classical electromagnetism is even required, remains controversial. A new theoretical approach is presented in this paper to address this using relativistic electromagnetic energy inertial frame transformations. These transformations identify a situation where an apparent violation of conservation laws could occur and how to consolidate this with electromagnetic theory. An explanation regarding the elementary nature of magnetism and the relationship between inertia and electromagnetic energy is also commented on.
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Tuning of the Magnetocaloric Properties of Mn5Ge3 Compound by Chemical Modification
Magnetism 2022, 2(1), 56-73; https://doi.org/10.3390/magnetism2010005 - 03 Mar 2022
Abstract
The rare earth-free Mn5Ge3 compound shows magnetocaloric properties similar to those of pure Gd; therefore, it is a good candidate for magnetic refrigeration technology. In this work, we investigate the influence of chemical substitution on the crystal structure and the
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The rare earth-free Mn5Ge3 compound shows magnetocaloric properties similar to those of pure Gd; therefore, it is a good candidate for magnetic refrigeration technology. In this work, we investigate the influence of chemical substitution on the crystal structure and the magnetic, thermodynamic, and magnetocaloric properties of a polycrystalline Mn5Ge3 compound prepared by induction melting. For this purpose, we replaced 5% of the Mn with Cr or Co and 5% of the Ge with B or Al. The additional chemical elements were shown not to change the crystal structure of the parent compound (space group P63/mcm, No. 193). In the case of the magnetic properties, all samples remained ferromagnetic with the ordering temperature (TC) lower than for the original compound (TC = 295(1) K). The exception was the sample with B, where we observed an increase in TC by 3 K. The maximum value of the magnetic entropy change, |∆Sm|MAX (for a magnetic field change of 5 T), decreased from 7.1(1) for Mn5Ge3 to 6.2(1), 6.8(1), 4.8(1), and 5.8(1) J kg−1 K−1 for the alloys with B, Al, Cr, and Co, respectively. The adiabatic temperature change (∆Tad) (for a magnetic field change of 1 T) was determined from the specific heat measurements and was equal to 1.1(1), 1.2(1), 1.2(1), 0.8(1), and 0.8(1) K for Mn5Ge3, Mn5Ge2.85B0.15, Mn5Ge2.85Al0.15, Mn4.75Cr0.25Ge3, and Mn4.75Co0.25Ge3, respectively. The obtained data were compared with those from the literature. It was found that the substitution allowed for tuning of the ordering temperature in a wide temperature range. At the same time, the reduction in the magnetocaloric parameters’ values was relatively small. Therefore, the produced Mn5Ge3-based alloys allow for the expansion of the operation temperature range of the parent compound as a magnetocaloric material.
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(This article belongs to the Special Issue Magnetocaloric Effect: Theory and Experiment in Concert)
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Calcination Temperature Reflected Structural, Optical and Magnetic Properties of Nickel Oxide
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, , , and
Magnetism 2022, 2(1), 45-55; https://doi.org/10.3390/magnetism2010004 - 16 Feb 2022
Cited by 1
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Stoichiometric compositions of NiO were prepared by the standard chemical co-precipitation method to inspect the effect of the calcination temperature on structures, morphology, and physical properties. The samples were calcined at three different temperatures viz. 350 °C, 550 °C, and 650 °C for
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Stoichiometric compositions of NiO were prepared by the standard chemical co-precipitation method to inspect the effect of the calcination temperature on structures, morphology, and physical properties. The samples were calcined at three different temperatures viz. 350 °C, 550 °C, and 650 °C for 5 h. X-ray diffraction analysis confirmed the cubic (Fm-3m) structure of the prepared samples. The average crystalline size increases from 41 nm to above 100 nm as the calcination temperature increases in the same time period. In Fourier transform infrared spectra, the spectral absorption bands were observed at ~413, 434, and 444 cm–1. The bandgap energy of NiO particles is decreased from 3.6 eV to 3.41 eV as the calcination temperature increases. The magnetic analysis confirms that the magnetization value of NiO is invariably decreased with a rise in the calcination temperature.
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Magnetism of Tetragonal β-Fe3Se4 Nanoplates Controllably Synthesized by Thermal Decomposition of (β-Fe2Se3)4[Fe(tepa)] Hybrid
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, , , , , , , and
Magnetism 2022, 2(1), 31-44; https://doi.org/10.3390/magnetism2010003 - 01 Feb 2022
Abstract
We report magnetism of tetragonal β-Fe3Se4 nanoplates controllably synthesized by thermal decomposition at 603 K of inorganic–organic (β-Fe2Se3)4[Fe(tepa)] hybrid nanoplates (tepa = tetraethylenepentamine). (β-Fe2Se3)4[Fe(tepa)] hybrid precursor and β-Fe
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We report magnetism of tetragonal β-Fe3Se4 nanoplates controllably synthesized by thermal decomposition at 603 K of inorganic–organic (β-Fe2Se3)4[Fe(tepa)] hybrid nanoplates (tepa = tetraethylenepentamine). (β-Fe2Se3)4[Fe(tepa)] hybrid precursor and β-Fe3Se4 nanoplates are in single crystal features as characterized by selected area electron diffraction. Rietveld refinements reveal that ordered inorganic–organic (β-Fe2Se3)4[Fe(tepa)] hybrid nanoplates are in a tetragonal layered crystal structure with a space group of I4cm (108) and room-temperature lattice parameters are a = 8.642(0) Å and c = 19.40(3) Å, while the as-synthetic tetragonal β-Fe3Se4 nanoplates have a layered crystal structure with the P4/nmm space group, and room-temperature lattice parameters are a = 3.775(8) Å and c = 5.514(5) Å. Magnetic measurements show the weak ferrimagnetism for (β-Fe2Se3)4[Fe(tepa)] hybrid nanoplates at room temperature, while the as-synthetic β-Fe3Se4 nanoplates are antiferromagnetic in a temperature range between 120 and 420 K but in a ferrimagnetic feature below ~120 K. The as-synthetic β-Fe3Se4 nanoplates are thermally instable, which are transformed to ferrimagnetic β-Fe3Se4 nanoplates by annealing at 623 K (a little higher than the synthetic temperature). There is an irreversible change from antiferromagnetism of the as-synthetic β-Fe3Se4 phase to the ferrimagnetism of the as-annealed β-Fe3Se4 phase in a temperature between 420 and 470 K. Above 470 K, the tetragonal β-Fe3Se4 phase transforms to monoclinic Fe3Se4 phase with a Curie temperature (TC) of ~330 K. This discovery highlights that crystal structure and magnetism of Fe-Se binary compounds are highly dependent on both their phase compositions and synthesis procedures.
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(This article belongs to the Special Issue Exclusive Collection: Papers from the Editorial Board Members of Magnetism)
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An Analytical Approach for Computing the Coefficient of Refrigeration Performance in Giant Inverse Magnetocaloric Materials
Magnetism 2022, 2(1), 10-30; https://doi.org/10.3390/magnetism2010002 - 13 Jan 2022
Abstract
An analytical approach for computing the coefficient of refrigeration performance (CRP) was described for materials that exhibited a giant inverse magnetocaloric effect (MCE), and their governing thermodynamics were reviewed. The approach defines the magnetic work input using thermodynamic relationships rather than isothermal magnetization
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An analytical approach for computing the coefficient of refrigeration performance (CRP) was described for materials that exhibited a giant inverse magnetocaloric effect (MCE), and their governing thermodynamics were reviewed. The approach defines the magnetic work input using thermodynamic relationships rather than isothermal magnetization data discretized from the literature. The CRP was computed for only cyclically reversible temperature and entropy changes in materials that exhibited thermal hysteresis by placing a limit on their operating temperature in a thermodynamic cycle. The analytical CRP serves to link meaningful material properties in first-order MCE refrigerants to their potential work and efficiency and can be employed as a metric to compare the behaviors of dissimilar alloy compositions or for materials design. We found that an optimum in the CRP may exist that depends on the applied field level and Clausius–Clapeyron (CC) slope. Moreover, through a large literature review of NiMn-based materials, we note that NiMn(In/Sn) alloys offer the most promising materials properties for applications within the bounds of the developed framework.
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(This article belongs to the Special Issue Magnetocaloric Effect: Theory and Experiment in Concert)
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MnBi2Se4-Based Magnetic Modulated Heterostructures
Magnetism 2022, 2(1), 1-9; https://doi.org/10.3390/magnetism2010001 - 04 Jan 2022
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Thin films of magnetic topological insulators (TIs) are expected to exhibit a quantized anomalous Hall effect when the magnetizations on the top and bottom surfaces are parallel and a quantized topological magnetoelectric effect when the magnetizations have opposite orientations. Progress in the observation
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Thin films of magnetic topological insulators (TIs) are expected to exhibit a quantized anomalous Hall effect when the magnetizations on the top and bottom surfaces are parallel and a quantized topological magnetoelectric effect when the magnetizations have opposite orientations. Progress in the observation of these quantum effects was achieved earlier in the films with modulated magnetic doping. On the other hand, the molecular-beam-epitaxy technique allowing the growth of stoichiometric magnetic van der Waals blocks in combination with blocks of topological insulator was developed. This approach should allow the construction of modulated heterostructures with the desired architecture. In the present paper, based on the first-principles calculations, we study the electronic structure of symmetric thin film heterostructures composed of magnetic MnBi Se blocks (septuple layers, SLs) and blocks of Bi Se TI (quintuple layers, QLs) in dependence on the depth of the magnetic SLs relative to the film surface and the TI spacer between them. Among considered heterostructures we have revealed those characterized by nontrivial band topology.
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Fast and Robust Capacitive Imaging of Cylindrical Non-Metallic Media
Magnetism 2021, 1(1), 60-69; https://doi.org/10.3390/magnetism1010006 - 03 Dec 2021
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In this paper, a unique approach to the imaging of non-metallic media using capacitive sensing is presented. By using customized sensor plates in single-ended and differential configurations, responses to hidden objects can be captured over a cylindrical aperture surrounding the inspected medium. Then,
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In this paper, a unique approach to the imaging of non-metallic media using capacitive sensing is presented. By using customized sensor plates in single-ended and differential configurations, responses to hidden objects can be captured over a cylindrical aperture surrounding the inspected medium. Then, by processing the acquired data using a novel imaging technique based on the convolution theory, Fourier and inverse Fourier transforms, and exact low resolution electromagnetic tomography (eLORETA), images are reconstructed over multiple radial depths using the acquired sensor data. Imaging hidden objects over multiple depths has wide range of applications, from biomedical imaging to nondestructive testing of the materials. Performance of the proposed imaging technique is demonstrated via experimental results.
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Topological Spin Textures and Their Applications
Magnetism 2021, 1(1), 58-59; https://doi.org/10.3390/magnetism1010005 - 02 Dec 2021
Abstract
Topological spin textures have been an extremely hot topic since their first experimental observation in 2009 [...]
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(This article belongs to the Special Issue Topological Spin Textures and Their Applications)
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Correlation between the Flow and Curing Behavior of Hard Magnetic Fillers in Thermosets and the Magnetic Properties
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Magnetism 2021, 1(1), 37-57; https://doi.org/10.3390/magnetism1010004 - 27 Nov 2021
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Polymer bonded magnets based on thermoplastics are economically produced by the injection molding process for applications in sensor and drive technology. Especially the lack of orientation in the edge layer, as well as the chemical resistance and the creep behavior limit the possible
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Polymer bonded magnets based on thermoplastics are economically produced by the injection molding process for applications in sensor and drive technology. Especially the lack of orientation in the edge layer, as well as the chemical resistance and the creep behavior limit the possible implementations of thermoplastic based polymer bonded magnets. However, thermoset based polymer bonded magnets have the opportunity to expand the applications by complying with the demands of the chemical industry or pump systems through to improved chemical and thermal resistance, viscosity and creep behavior of thermosets. This paper investigates the influence of hard magnetic particles on the flow and curing behavior of highly filled thermoset compounds based on an epoxy resin. The basic understanding of the behavior of those highly filled hard magnetic thermoset systems is essential for the fabrication of polymer bonded magnets based on thermosets in the injection molding process. It is shown that several factors like the crystal structure, the particle shape and size, as well as the thermal conductivity and the adherence between filler and matrix influence the flow and curing behavior of highly filled thermoset compounds based on epoxy resin. However, these influencing factors can be applied to any filler system with respect to a high filler amount in a thermoset compound, as they are based on the material behavior of particles. Further, the impact of the flow and curing behavior on the magnetic properties of polymer bonded magnets based on thermosets is shown. With that, the correlation between material based factors and magnetic properties within thermosets are portrayed.
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Ferroelectric and Dielectric Properties of Strontium Titanate Doped with Barium
Magnetism 2021, 1(1), 22-36; https://doi.org/10.3390/magnetism1010003 - 11 Nov 2021
Abstract
Ferroelectric samples Sr1−xBaxTiO3 (BST), where x = 0, 0.2, 0.4, 0.6, 0.8 and 1, were prepared using the tartrate precursor method and annealed at 1200 °C for 2 h. X-ray diffraction, “XRD”, pattern analysis verified the structure phase.
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Ferroelectric samples Sr1−xBaxTiO3 (BST), where x = 0, 0.2, 0.4, 0.6, 0.8 and 1, were prepared using the tartrate precursor method and annealed at 1200 °C for 2 h. X-ray diffraction, “XRD”, pattern analysis verified the structure phase. The crystallite size of the SrTiO3 phase was calculated to be 83.6 nm, and for the TiO2 phase it was 72.25 nm. The TEM images showed that the crystallites were agglomerated, due to their nanosize nature. The AC resistivity was measured as temperature dependence with different frequencies 1 kHz and 10 kHz. The resistivity was decreased by raising the frequency. The dielectric properties were measured as the temperature dependence at two frequencies, 1 kHz and 10 kHz. The maximum amount of dielectric constant corresponded to the Curie temperature and the transformation from ferroelectric to paraelectric at 1 kHz was sharp at 10 kHz. Polarization–electric field hysteresis loops for BST samples were measured using a Sawer–Tawer modified circuit. It was shown that the polarization decreased with increasing temperature for all samples.
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(This article belongs to the Special Issue Magnetocaloric Effect: Theory and Experiment in Concert)
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Injection Moulding of Multipolar Polymer-Bonded Magnets into Soft Magnetic Inserts for Rotors in Reluctance Motors
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and
Magnetism 2021, 1(1), 3-21; https://doi.org/10.3390/magnetism1010002 - 26 Oct 2021
Cited by 1
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Due to lower magnetic properties of polymer-bonded magnets compared to sintered magnets, a complete redesign of the multipolar soft magnetic flux barriers in rotors with alignment guidelines was carried out to eliminate the frequently used rare-earth magnets, causing a new influence of the
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Due to lower magnetic properties of polymer-bonded magnets compared to sintered magnets, a complete redesign of the multipolar soft magnetic flux barriers in rotors with alignment guidelines was carried out to eliminate the frequently used rare-earth magnets, causing a new influence of the outer magnetic field on the cavity by using soft magnetic inserts. Within this new process, the main influencing factors on the magnetic flux density such as filler content, tool temperature, holding pressure and injection velocity were analysed and correlated. The studies were based on the compound of Polyamide 12 and up to a 60 vol.-% of the hard magnetic filler, strontium ferrite. Based on the study, the injection moulding of multipolar-bonded magnets into soft magnetic inserts for rotors and, in turn, into complex geometries can be optimized in terms of the orientation of the filler, the microstructure and the magnetic flux density. The investigations show no significant influence of the process parameters known from the literature such as the mass temperature Tm, which affects the magnetic flux density, as well as the orientation and the microstructure similar to tool temperature Tt, but is less efficient. The main influencing factors identified during the investigations are the tool temperature Tt, the injection velocity vin and the holding pressure ph. As known influencing factors are only based on simple geometries such as ring structures or plates, new factors were determined for complex rotor geometries.
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Open AccessEditorial
Welcome to Magnetism: A New Open Access Scientific Journal on Magnetism, Magnetic Materials and Magnetic Technology
Magnetism 2021, 1(1), 1-2; https://doi.org/10.3390/magnetism1010001 - 18 Mar 2021
Abstract
Magnetism has been entangled with human progress since the first realization by Chinese civilization of the attractive interactions between loadstone and iron, which they attributed to a similar qi (vital force) [...]
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Exclusive Collection: Papers from the Editorial Board Members of Magnetism
Guest Editor: Gerardo F. GoyaDeadline: 31 July 2022
Special Issue in
Magnetism
Magnetic Low-Dimensional Structures and Hybrid Materials
Guest Editors: Da Li, Teng YangDeadline: 1 September 2022
Special Issue in
Magnetism
Topological Spin Textures and Their Applications
Guest Editors: Xichao Zhang, Israa Medlej, Roberto ZivieriDeadline: 30 September 2022
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Magnetism
Magnetocaloric Effect: Theory and Experiment in Concert
Guest Editors: Tarek Bachagha, Joan-Josep SuñolDeadline: 31 October 2022