Search Results (8)
Enhancing the performance of highly filled polymerbonded Nd-Fe-B magnets: Integrated advanced surface treatments and additive manufacturing
This doctoral dissertation present research aimed into enhancing polymer-bonded Nd–Fe–B magnets through innovative surface treatments and additive manufacturing techniques, focusing on improving their mechanical strength, magnetic characteristics, and environmental stability. This research is critical for broadening the applicability of these magnets in sectors like green technologies and motion control systems. …
Mechanisms for colloidal stabilization of magnetic nanoplatelets
The dissertation presents a study of the colloidal stabilization of ferrimagnetic barium hexaferrite nanoplatelets in various isotropic and nematic media for the preparation of ferromagnetic fluids. Colloidal stability is the most important requirement to obtain a ferromagnetic liquid of barium hexaferrite nanoplatelets that exhibits spontaneous magnetization in the absence of …
Processing of heavy-rare-earth-lean Nd-Fe-B permanent magnets for high-temptrature applications
Permanent magnets are materials that generate a magnetic field in free space without electricity or other external energy sources. They are essential components of modern technologies, used in many electrical devices. Nowadays, they are included in technology for renewable sources of energy, such as electrical vehicles, generators and wind turbines. …
Heterogeneous nucleation of iron oxide (γ-Fe2O3) in colloidal systems
Presented work is a study of magnetic iron oxide (referred to as spinel) coating synthesis. The coatings were synthesized on the surfaces of selected core nanoparticles with heterogeneous nucleation during the co-precipitation of the Fe3+/Fe2+ ions. The work is divided into three parts. The first part comprise the synthesis of …
Laser Ablation - Inductively Coupled Plasma Mass Spectrometry (LA-ICPMS) - Fundamental Study of Ablation and Deposition Processes
Laser ablation (LA) is a versatile technique that can be used for the elemental analysis of diverse materials as well as for synthesis purposes, i.e. for pulsed laser deposition (PLD) of a wide range of materials. Analysis and synthesis will only be successful if the ablated material can be stoichiometrically …
Radio wave propagation in special environments
In this doctoral thesis, radio signal propagation in special environments is discussed. The primary focus is on the development of a path loss model for radio signal propagation in long road tunnels and underground passageways, which allows a rather precise calculation of radio signal path loss and, consequently, a quick …
Microstructural investigations of rare-earth transition-metal-based magnetocaloric materials for near-room-temperature applications
Magnetocaloric materials are promising materials for magnetic refrigerators which would substitute present compressor refrigerators. They work on the principle of the magnetocaloric effect (MCE), where the magnetocaloric material increases its temperature when exposed to an external magnetic field. These new type of refrigerators are energetically more efficient and environmentally friendly. …
Hydrogen absorption in Ti-Zr-Ni alloys
Our research focused on the formation of Ti40Zr40-xNi20Cux (x=3, 5), Ti45Zr38-xNi17Cux (x=3, 5), Ti53Zr27-xNi20Cux (x=3, 5) and Ti58Zr24-xNi18Cux (x=3, 5) icosahedral (i-phase) quasicrystals by three different techniques and their subsequent characterization and high-pressure hydrogenation. The quasicrystals of this system are thermodynamically stable and they have a relatively good affinity for …