A5001294491- Magnetic Properties of Alloys
- Magnetic and transport properties of perovskites and related materials
- Rare-earth and actinide compounds
- Shape Memory Alloy Transformations
- Magnetic properties of thin films
- Magnetic Properties and Applications
- Hydrogen Storage and Materials
- Metallic Glasses and Amorphous Alloys
- Heusler alloys: electronic and magnetic properties
- Thermal Expansion and Ionic Conductivity
- Advanced Thermoelectric Materials and Devices
- High-pressure geophysics and materials
- Geomagnetism and Paleomagnetism Studies
- Metallurgical and Alloy Processes
- Multiferroics and related materials
- High Entropy Alloys Studies
- Additive Manufacturing Materials and Processes
- Intermetallics and Advanced Alloy Properties
- Magnetic and Electromagnetic Effects
- Microstructure and Mechanical Properties of Steels
- Ferroelectric and Piezoelectric Materials
- Advanced Condensed Matter Physics
- Physics of Superconductivity and Magnetism
- Inorganic Chemistry and Materials
- Superconducting Materials and Applications
Technical University of Darmstadt
2016-2025
South Ural State University
2019-2024
Chelyabinsk State University
2015-2022
Leibniz Institute for Solid State and Materials Research
2010-2021
Technische Universität Dresden
2021
Tver State University
2007-2020
Robert Bosch (Germany)
2019
National University of Science and Technology
2016-2019
Uppsala University
2015-2019
Universidad de Sevilla
2016
Abstract The ideal magnetocaloric material would lay at the borderline of a first-order and second-order phase transition. Hence, it is crucial to unambiguously determine order transitions for both applied research as well characterization other change materials. Although Ehrenfest provided conceptually simple definition transition, known techniques its determination based on magnetic measurements either provide erroneous results specific cases or require extensive data analysis that depends...
Abstract The phase‐down scenario of conventional refrigerants used in gas–vapor compressors and the demand for environmentally friendly efficient cooling make search alternative technologies more important than ever. Magnetic refrigeration utilizing magnetocaloric effect magnetic materials could be that alternative. However, there are still several challenges to overcome before having devices competitive with those based on technology. In this paper a rigorous assessment most relevant...
We report on the high irreversible adiabatic temperature change of −8 K in a magnetic field 1.95 T Heusler compound Ni45.7Mn36.6In13.5Co4.2 showing first-order magnetostructural transition. Due to large thermal hysteresis 10 K, this ΔTad cannot be obtained cyclic way but still reversible magnetocaloric effect amounts −3 K—an unexpectedly value which compares La(Fe,Si,Co)13. In order reveal nature effect, in-situ dependent optical microscopy minor loops has been done.
Hysteresis is more than just an interesting oddity, which occurs in materials with a first-order transition. It real obstacle on the path from existing lab-scale prototypes of magnetic refrigerators towards commercialization this potentially disruptive cooling technology. Indeed, reversibility magnetocaloric effect, being essential for heat pumps, strongly depends width thermal hysteresis and therefore it necessary to understand mechanisms causing find solutions how minimize losses...
The magnetization of a Ho${}_{2}$Fe${}_{17}$ single crystal has been measured along the principal crystallographic directions in pulsed magnetic fields up to 60 T. Stepwise discontinuities occur at 45 and 55 T [120] [100] directions, respectively. data allowed us deduce molecular field Ho site. As cross check, was determined as well from measurement when let rotate freely. Both values are good agreement with each other.
We have investigated the anisotropy of magnetocaloric effect in a ${\mathrm{NdCo}}_{5}$ single crystal wide range temperatures, including spin-reorientation temperature region. In field ${\ensuremath{\mu}}_{0}H=1.3\text{ }\text{ }\mathrm{T}$ region 250--310 K, we discovered giant rotating $\ensuremath{\sim}1.6\text{ }\mathrm{K}$, caused by rotation magnetization vector. The calculations for been carried out.
Magnetic cooling prototypes based on the magnetocaloric effect require magnetic refrigerant to be shaped into geometries that enable quick and efficient heat-transfer transfer fluid. Simple solutions include a stack of parallel-plates or bed packed-spheres. Here, we demonstrate how more sophisticated can made by using selective laser melting, rapid prototyping technique form three-dimensional shapes. Using excellent La(Fe,Co,Si)13 as starting-powder two geometries: wavy-channel block with...
In this paper, we illustrate the dilemma of inverse magnetocaloric materials using example Heusler alloys. For such materials, magnetic and lattice contribution to total entropy change are competing with each other. two paradigmatic systems Ni-Mn-In Ni-Mn-In-Co, provide a systematic comparison experimental data under different fields hydrostatic pressures properties obtained from Heisenberg model. This allows us separate martensitic transition. Our analysis reveals that large magnetization...
Achieving a very strong magnetic anisotropy in 3d material is difficult, but not an impossible task. It difficult because there no general recipe (necessary condition) for band magnet. Several strategies can be pursued this situation. One of them to re-examine the less studied compounds, somewhat neglected since discovery Nd-Fe-B magnets 30 years ago. As example, single crystal (Fe0.7Co0.3)2B has been investigated work.
Hysteresis features of the direct and inverse magnetocaloric effect associated with first-order magnetostructural phase transitions in Ni-Mn-X (X $=$ Ga, Sn) Heusler alloys have been disclosed by differential calorimetry measurements performed either under a constant magnetic field, $H$, or varying $H$ isothermal conditions. We shown that these crucially depends on employed measuring protocol. Experimentally observed peculiarities explained framework model accounts for different...
Abstract Magnetic refrigeration relies on a substantial entropy change in magnetocaloric material when magnetic field is applied. Such changes are present at first‐order magnetostructural transitions around specific temperature which the applied induces phase transition and causes conventional or inverse effect (MCE). First‐order show large effects, but involve transitional hysteresis, loss source that hinders reversibility of adiabatic Δ T ad . However, required for efficient operation heat...
The magnetocaloric effect of gadolinium has been measured directly in pulsed magnetic fields up to $62\phantom{\rule{0.16em}{0ex}}\mathrm{T}$. maximum observed adiabatic temperature change is $\mathrm{\ensuremath{\Delta}}{T}_{\mathrm{ad}}=60.5\phantom{\rule{0.16em}{0ex}}\mathrm{K}$, the initial ${T}_{0}$ being just above $300\phantom{\rule{0.16em}{0ex}}\mathrm{K}$. field dependence $\mathrm{\ensuremath{\Delta}}{T}_{\mathrm{ad}}$ found follow usual ${H}^{2/3}$ law, with a small correction...
Magnetocaloric hydrogen liquefaction could be a "game-changer" for liquid industry. Although heavy rare-earth-based magnetocaloric materials show strong effects in the temperature range required by (77 ~ 20 K), high resource criticality of rare-earth elements is major obstacle upscaling this emerging technology. In contrast, higher abundances light make their alloys highly appealing liquefaction. Via mean-field approach, it demonstrated that tuning Curie ($T_C$) an idealized material towards...