Extremely polysubstituted magnetic material based on magnetoplumbite with a hexagonal structure: Synthesis, structure, properties, prospects

Crystalline high-entropy single-phase products with a magnetoplumbite structure with grains in the µm range were obtained using solid-state sintering. The synthesis temperature was up to 1400 °C. The morphology, chemical composition, crystal structure, magnetic, and electrodynamic properties were studied and compared with pure barium hexaferrite BaFe 12 O 19 matrix. The polysubstituted high-entropy single-phase product contains five doping elements at a high concentration level. According to the EDX data, the new compound has a formula of Ba(Fe6Ga1.25In1.17Ti1.21Cr1.22Co1.15)O19. The calculated cell parameter values were a = 5.9253(5) Å, c = 23.5257(22) Å, and V = 715.32(9) Å3. The increase in the unit cell for the substituted sample was expected due to the different ionic radius of Ti/In/Ga/Cr/Co compared with Fe3+. The electrodynamicmeasurements were performed. The dielectric and magnetic permeabilities were stable in the frequency range from 2 to 12 GHz. In this frequency range, the dielectric and magnetic losses were??0.2/0.2. Due to these electrodynamic parameters, this material can be used in the design of microwave strip devices. © 2019 by the authors. Licensee MDPI, Basel, Switzerland.Funding: The work was supported by the Russian Science Foundation, project No. 18-73-10049

Adaptive system with frequency control channel division and bootstrapping

Construction of adaptive control system on the basis of the principle of frequency-dependable feedback and with application of multi-frequency identification action has been shown. The adaptation algorithm possesses relative simplicity, accuracy suitable for most of the industrial enterprises, does not require large calculating resources and is capable of operating in the real time mode

Effects of severe plastic deformation on the magnetic properties of terbium

We report on the magnetic and magnetocaloric properties of Terbium ribbons subjected by cold rolling. The magnetic entropy change ΔS = 8.66 J/(kg·K) and adiabatic temperature change ΔT = 4.38 K for a bulk sample of Terbium in an external magnetic field change of 1.9 T are larger by about 12% and 26% respectively, than those values of cold rolled Terbium. The changes are fully reversible and can be fully restored by an additional annealing

Effects of severe plastic deformation on the magnetic properties of terbium

We report on the magnetic and magnetocaloric properties of Terbium ribbons subjected by cold rolling. The magnetic entropy change ΔS = 8.66 J/(kg·K) and adiabatic temperature change ΔT = 4.38 K for a bulk sample of Terbium in an external magnetic field change of 1.9 T are larger by about 12% and 26% respectively, than those values of cold rolled Terbium. The changes are fully reversible and can be fully restored by an additional annealing