A5001919064- Magnetic properties of thin films
- Metallic Glasses and Amorphous Alloys
- Magnetic Properties of Alloys
- Magnetic Properties and Applications
- Characterization and Applications of Magnetic Nanoparticles
- Nanoparticle-Based Drug Delivery
- Advanced materials and composites
- Magneto-Optical Properties and Applications
- Rare-earth and actinide compounds
- Aluminum Alloys Composites Properties
- Theoretical and Computational Physics
- Vibration Control and Rheological Fluids
- Nanoparticles: synthesis and applications
- Electric Motor Design and Analysis
- Thin-Film Transistor Technologies
- Microstructure and Mechanical Properties of Steels
- Magnetic Properties and Synthesis of Ferrites
- Fluid Dynamics and Vibration Analysis
- Superconducting Materials and Applications
- ZnO doping and properties
- Phase-change materials and chalcogenides
- Iron oxide chemistry and applications
- Diamond and Carbon-based Materials Research
- Analytical Chemistry and Sensors
- Magnetism in coordination complexes
National Institute of Research and Development for Technical Physics
2012-2024
NTL Institute for Applied Behavioral Science
2011
Alexandru Ioan Cuza University
2010
The surface magnetization processes taking place in simple permalloy (Py) and FeGa nanowires, Py/Cu, CoFeB/Cu, CoNiP/Cu, FeGa/Py, FeGa/CoFeB multilayered nanowires have been studied by magneto-optical Kerr effect (MOKE) magnetometry. results indicate a strong correlation between the direction of anisotropy axis relative to applied field plane incidence laser spot, as well dipolar interactions or ferromagnetic layers on reversal. larger spots are inducing more noise MOKE hysteresis loops...
Results on the preparation and magnetic characterization of rapidly solidified amorphous glass-coated nanowires are reported. Rapidly have been investigated by means bulk surface hysteresis loop measurements, scanning electron microscopy, ferromagnetic resonance. Domain wall velocity has measured to demonstrate suitability new for spintronic applications. Changes in composition, thickness glass coating, nanowire dimensions allow extensive tailoring domain mobility.
Results on the magnetic behavior of glass-coated amorphous wires with metallic nucleus diameters in submicron range are reported for first time. The nearly zero magnetostrictive is different from that observed microwires typical dimensions and similar composition. Submicron bistable, whereas show an almost anhysteretic loop. Bistability maintained even a very thin surface layer, which was shown to display helical anisotropy. origin this specific shape anisotropy becomes dominant at lower...
Rapidly solidified submicron amorphous wires with positive and nearly zero magnetostriction are studied in order to understand the effect that a significant reduction diameter of metallic nucleus has on their magnetic behavior anisotropy distribution. Submicron diameters between 350 800 nm were investigated hysteresis loop measurements, magneto-optical Kerr effect, ferromagnetic resonance studies. The analysis results shows dominant role shape magnetostrictive wires, as well ones smaller...
Fe79.7−xNb0.3CrxB20 (x = 11.5–13.5 at. %) submicron powders with glassy structure and sizes between a few tens of nm 1 μm have been prepared by high-energy ball milling from melt-spun ribbons (MSRs) precursors. The existing in the MSRs, consisting Fe-Cr clusters embedded within (Fe,Nb)3B residual amorphous matrix, is preserved annealed MSRs oleic acid n-heptane. confers specific magnetic properties allows tuning Curie temperatures range 15–50 °C. precipitation α-Fe excess shifts temperature...
The controlled nucleation and propagation of magnetic domain walls in ultrathin ferromagnetic wires, such as nanowires submicrometer is extremely important for the development new high performance wall logic devices. Therefore, it equally essential to possess adequate advanced experimental investigation techniques order be able achieve a comprehensive situ analysis many possible parameters related propagation, e.g., shape besides velocity position. In this paper, we report on method...
The aim of this work was to investigate and prove the possibility real-time detection magnetic nanoparticles (MNPs) distributed in solid material by using a tunnel magnetoresistance-based (TMR) sensor. Following tests FeCrNbB transparent epoxy resin (EPON 812) measuring sensor output voltage changes at different particle concentrations, ability demonstrated. For proposed TMR sensor, we measured maximum magnetoresistance ratio about 53% sensitivity 1.24%/Oe. This type could facilitate new...
Currently, various methods based on magnetic nanoparticles are being considered for the treatment of cancer. Among these, hyperthermia and magneto-mechanical actuation most tested physical that have shown promising results when applied both separately in combination. However, combining them with specific drugs can further improve antitumor efficiency. In this study, we performed a systematic analysis to determine best combination hyperthermia, silver-coated magnetite (MNP@Ag) chemotherapy...
Magnetorheological fluids were prepared using FeSiB particles with an irregular flattened shape and also spherical Fe commercially available. In this paper we point out that oxidation size distribution can influence the MR fluid performance measurements.
α″-Fe16N2 materials are of increasing interest for their applications in products such as rare earth-free permanent magnets. The lack a method mass production powders raw delays the preparation Through employing gas atomization method, we managed to prepare whose morphology and magnetic properties were tailored by parameters. As result optimizing parameters (ejection temperature pressure, ejection nozzle diameter, pressure), with size about 30 μm content 31% phase. value saturation...
Results on the study of surface magnetization process and domain structure by magneto-optical Kerr effect in conventional rapidly quenched amorphous magnetic wires are reported. Domain imaging confirms presence a bamboo-type near-surface region these materials. Surface loops show that overall has large axial component, besides circular one. A bistable behavior direction been emphasized. circularly applied field leads to disappearance bistability. changed 180° interdomain walls region.
Composite magnets were obtained by spark plasma sintering (SPS) consolidation of a mixture ball-milled powders prepared from nonstoichiometric Nd15Fe79B6 and Nd16Fe78B6 nanocrystalline melt-spun ribbons, and, respectively, Fe77.5Si7.5B15 Co68.25Fe4.5Si12.25B15 amorphous wires 100–125 μm in diameter in-rotating water quenching method. The have been mixed different weight ratios the was done at pressures 50 70 MPa, respectively. addition FeSiB CoFeSiB soft magnetic increases remanent...
The effect of annealing and applied stresses on the magnetic properties giant magneto-impedance in as-cast cold drawn FINEMET wires has been studied. results show major changes evolution permeability, coercivity, response with drawing stages. These have explained considering structural transformations, intrinsic, applied, drawing-induced stresses, as well their global magnetostriction wires. observed sensitivity to recommends this class nanocrystalline for applications miniaturized sensors...
The iron nitride materials, especially α″-Fe16N2, are considered one of the most promising candidates for future rare-earth-free magnets. However, mass production α″-Fe16N2 powders as a raw material permanent magnets is still challenging. In this work, starting from lumps material, we have managed to prepare via gas atomization method, followed by subsequent nitriding in an ammonia–hydrogen mixture stream. particle size was controlled changing preparation conditions. X-ray diffractograms...
Nearly zero magnetostrictive microwires have been proven to be very versatile, due their extremely soft magnetic properties, the changes in magnetization mechanism with dimensions, and appearance of sensitive application-related effects, such as large Barkhausen giant magnetoimpedance effects. Their response originates specific domain structure, composed an inner core outer shell (OS), since OS a circumferential easy axis is main region involved effect. The believed display bamboolike...
This paper presents the influence of sintering on structure, morphology and compressing strength alumina/nickel composite compacts obtained by spark plasma (SPS). Al2O3/Ni composites were prepared SPS in argon atmosphere at temperatures range 1000–1200 –C with a holding time 2, 5 10 minutes. The heating rate was 200 C min−1. These have been characterised X-ray diffraction, SEM EDX. relative density compressive as-obtained determined. results showed that alumina particles are uniformly...
Surface magnetization processes in ferromagnetic glass-coated amorphous microwires with positive, negative, and nearly zero magnetostriction have been investigated. The results indicate helical the surface region of positive magnetostrictive enhanced soft magnetic properties on axial direction. typical bistable behavior such is maintained within region. Nearly diameters larger than 20 ¿m also display bistability region, whilst negative ones are not bistable. values metallic nucleus diameter...
Results on the control of domain wall displacement in cylindrical Fe77.5Si7.5B15 amorphous glass-coated submicron wires prepared by rapid quenching from melt are reported. The methods have relied conical notches with various depths, up to a few tens nm, made glass coating and metallic nucleus using focused ion beam (FIB) system, use small nucleation coils at one sample ends order apply magnetic field pulses aimed enhance reverse domains. notch-based method is used for first time case...