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The microstructure and high temperature magnetic properties of Fe-Co-2V and Fe-Co-2V-0.3Nb alloys are investigated. In the Fe-Co alloys the soft magnetic property are strongly influenced by the gamma2 phase precipitated at high temperature.

The hysteretic losses of a series of eight nanocrystalline soft magnetic alloys with compositions (Fe,Co,Ni)-Zr-B-Cu are investigated. The lower coercivity values observed in alloys containing Cu are attributed to grain refinement and the reduction in hysteresis losses is observed for the nanocrystalline alloy with composition [([Fe.sub.0.75][Co.sub.0.125][Ni.sub.0.125]).sub.85.5][Zr.sub.8.5][B.sub.5][Cu.sub.1].

The non-resonant and soft resonant magnetic x-ray scattering technique is employed to explain the impact of annealing on the junction profile of the various different CoFeB/MgO tunnel junctions. The structural quality of the junctions is shown to remain unaffected by the annealing procedure.

An anomalous angular dependence of the coercive field of physically nonpercolated granular CoFeB-Si[O.sub.2] films with oriented anisotropy of the granules, where the presence of the superferromagnetic phase is established, is seen at temperatures above the blocking temperature. The studies have shown that the anomaly is determined by a singularity of the angular dependence of the critical field causing the absolute loss of the superferromagnetic phase stability in the ensemble of weakly interacting ferromagnetic nanoparticles.

The low-temperature anomaly is revealed in the temperature and angular dependencies of the coercivity in granular [(CoFeB)-[(Si[O.sub.2]).sub.1-x] films with oriented in-plane anisotropy. The results are described in terms of a random field model, which has described the onset of spin glass-like correlations in the ensemble of oriented weakly interacting Stoner-Wohlfarth particles.

The light and heat induced transformation between diamagnetic [Fe.sub.LS.II]([micro]-CN)[Co.sub.LS.sup.III] (LS = low spin) units and paramagnetic [Fe.sub.LS.sup.III]([micro]-CN)[Co.sub.HS.sup.II] (HS = high spin) units is exploited to show the photoswitched transformation from a paramagnetic state to an antiferromagnetic ordered single-chain magnet (SCM) state and the thermally induced reverse transformation. An effective way is provided to control the spin topology of the SCM through light or a thermally induced metal-to-metal charge transfer.

The article explains the microstructure, as well as the mganetocaloric effects of the various La[Fe.sub.10.8][Co.sub.0.7][Si.sub.1.5][C.sub.0.2] compounds observed at different annealing times. The grains of the compounds are shown to considerably increase with an increase in the annealing time.

The impact of temperature on the spontaneous remagnetization observed in the various [Nd.sub.60][Fe.sub.30][Al.sub.10] and [Nd.sub.60][Fe.sub.20][Co.sub.10][Al.sub.10] bulk amorphous ferromagnets is discussed. The spontaneous remagnetization measure is shown to increase linearly with the temperature.

The spark plasma sintering technique is employed to explain the structure, as well as the magnetic properties of the bulk nanocrystalline [Tm.sub.2][([Co.sub.1 - x][Fe.sub.x]).sub.17] permanent magnet. Optimal annealing is shown to lead to a sharp increase in the coercivity of the sintered magnet.

Several studies are conducted to explain the impact of the changes taking place in the B and Si contents on the glass-forming ability and soft-magnetic properties in [(Co.sub.0.89][Fe.sub.0.057][Nb.sub.0.053]).sub.100?x][([B.sub.0.8][Si.sub.0.2]).sub.x] glassy alloys. An increase in the B and Si contents is shown to lead to a significant enhancement in the thermal stability of the supercooled liquid.

The article discusses the synthesis, properties and applications of the various Fe-Co-Cr nanocomposites that are shown to exhibit low Curie temperatures and moderate magnetic moments. The compounds are shown to be widely used for self-regulated rf heating employed in polymer curing.

The article discusses a new approach, which can be used for the synthesis of the [Fe.sub.x][Co.sub.100?x] nanoparticles by employing a modified aqueous reduction of iron and cobalt sulfate. The crystallite size of the nanoparticles is shown to considerably increase with annealing.

Several studies are conducted to explain the various effects of temperature variation on the different magnetorestrictive properties of the Co[Al.sub.x][Fe.sub.2- x][O.sub.4] systems. The magnetorestriction, strain sensitivity and the other properties of the compounds are shown to be completely dependent on the temperature.

The magnetic force microscopy technique is employed to explain the structures and properties of the various magnetically annealed [Tb.sub.0.36][Dy.sub.0.64][([Fe.sub.0.85][Co.sub.0.15]).sub.2] polycrystals. Field annealing is shown to completely change the initial magnetic states of the crystals.

Several studies are conducted to explain the magnetic properties and the magnetocaloric effect of the different La[Fe.sub.11.2][Co.sub.0.7][Si.sub.1.1][C.sub.x] materials. The refrigerant capacity of the materials is shown to decrease with an increase in the C content of the materials.

Structurally gradient layered A1/[L1.sub.0] films are fabricated by heat treatment of magnetron sputter deposited FePt(20 nm)/CoPt(x nm) bilayers where x=0-120 nm. The magnetic properties of the films could be tuned by adjusting the layer thicknesses and using different heat-treatment temperatures required for the ordering of the [L1.sub.0] phase between FePt and CoPt.

The microstructure and local chemistry of Ta/Ru/Ta/CoFeB/MgO/CoFeB/Ta/Ru magnetic tunnel junctions are examined with different values of tunneling magnetoresistance (TMR) as a result of annealing at different temperatures. The degradation in TMR of the samples annealed at 650 [degree]C has resulted from the loss of bcc-CoFe (001) texture in the bottom CoFeB electrode because of the pronounced Ta diffusion into the CoFe/MgO/CoFe layers.

The magnetic and magnetocaloric properties of La[Fe.sub.11.9-y][Co.sub.y][Si.sub.1.1] compounds are examined. Direct measurements of the temperature change for La[Fe.sub.11.9-y][Co.sub.y][Si.sub.1.1] compounds are performed around room temperature and the isothermal entropy change is measured in adiabatic conditions with practice-oriented method by using a specially developed test bench.

The synthesis of [Nd.sub.25][Fe.sub.40][Co.sub.20][Al.sub.10][B.sub.5] by high-energy milling and melt-spinning techniques followed by subsequently annealed temperature range from 400 to 1100 degree Celsius for 20 min, is described. The findings from x-ray diffraction combined with high-resolution transmission microscopy for the annealed samples showed the presence of ferromagnetic [Nd.sub.2][(Fe,Co,Al).sub.14]B crystallites coexisting with antiferromagnetic [Nd.sub.6][(Fe,Co,Al).sub.14] ones, among an amorphous matrix.

FeCo magnetic nanoparticles (MNPs) are examined for curing polymer epoxy composites through radio-frequency (rf) heating and they are prepared by using rf induction plasma torch. The results have shown that rf heating of FeCo MNPs have provided an effective method for curing epoxy composites.

The exchange bias fields and compositional depth profiles of the NiFe/FeMn/CoFe trilayers after a thermal treatment at different annealing temperatures are examined. The in situ applied fields during sample growth and ex situ cooling fields after sample growth have a different effect on the exchange bias fields of both top and bottom interfaces.

The switching probability is dependent on bias voltage V and bias magnetic field H for bias voltage pulse durations t long enough to allow thermally activated reversal of CeFeB/MgO-based magnetic tunnel junctions. The probability of magnetic switching in spin-torque-driven switches has decreased due to a backhopping behavior occurring at high bias and it is asymmetric in bias voltage.

Pseudo-single-crystal Cu underlayer (UL) with thermal tolerance is obtained on base Si waver by using diffusion-blocking layer and magnetic tunnel junctions in a stacking sequence of [Fe.sub.4]N/MgO/CoFeB has displayed an inverse tunnel magnetoresistance (TMR) effect at room temperature. The largest magnitude of the TMR ratio, -75.1%, is obtained, where the large inverse TMR ratio is due to the improvement of the crystallinity of the [Fe.sub.4]N film as the small lattice is misfit between [Fe.sub.4]N and Cu.

The exchange-coupling fields of CeFe/Ru/CoFe synthetic antiferromagnetic (SyAF) structures with a Ru underlayer and capping layer before and after annealing are examined. The results have shown that distribution is caused by the existence of the AF coupling of various coupling fields due to annealing and a large exchange-coupling field after high temperature annealing is obtained by suppressing the distribution of the exchange coupling in the SyAF structure.

High-magnetic-moment [Fe.sub.70][Co.sub.30] nanoparticles with a cubic shape are prepared by using a gas condensation sputtering method for potential magnetic hyperthermia application. Micromagnetic simulation of the experimental hysteresis loop of the particles has shown that their behavior is dominated by a uniaxial anisotropy.

A new analysis approach is developed for evaluating the atomic ordering in full-Heusler alloys, which is extension of the commonly used Webster model. The model is applied to full-Heusler [Co.sub.2]FeSi alloy thin films formed by rapid thermal annealing.

Magnetic and magnetocaloric properties of single crystal [Er.sub.2][([Co.sub.0.4][Fe.sub.0.6]).sub.17] are examined. First order spin reorientation phase transition is observed at 272 K, magnetic easy-axis anisotropy is below this temperature and the easy-plane one above.

The temperature stability of field induced uniaxial anisotropy ([K.sub.U]) is examined by thermomagnetic treatments of [([Co.sub.1-x][Fe.sub.x]).sub.89][Zr.sub.7][B.sub.4] amorphous ribbons after field annealing below and the above the crystallization temperature. Field crystallization is required for elevated temperature applications when field induced anisotropy is vital for performance.