Components of Magnetic Anisotropy of Soft Magnetic Nanocrystalline Fe-Based Films

2015 ◽  
Vol 233-234 ◽  
pp. 619-622 ◽  
Author(s):  
E.V. Harin ◽  
Elena N. Sheftel
Keyword(s):  
Magnetron Sputtering ◽  
Magnetic Anisotropy ◽  
Hysteresis Loops ◽  
Anisotropy Field ◽  
The Other ◽  
Structure Parameters ◽  
Soft Magnetic ◽  
Local Anisotropy ◽  
Magnetoelastic Anisotropy ◽  
Residual Macrostresses

We present quantitative evaluation results of micromagnetic structure parameters of nanocrystalline Fe, Fe95Zr5, Fe90N10, and Fe85Zr5N10films obtained by magnetron sputtering. It is shown that quantities of magnetocrystallineK1, magnetoelasticKME, magnetostaticKMS, and surfaceKa,Sanisotropies are components of experimentally measured effective local anisotropyKeff. The shape of the hysteresis loops of the films is determined by the presence of two main macroscopic effective magnetic anisotropies, one of which is the anisotropy field of stochastic domains, and the other is the magnetoelastic anisotropy field due to residual macrostresses.

Influence of Magnetoelastic Anisotropy on Properties of Nanostructured Microwires

2013 ◽  
Vol 646 ◽  
pp. 59-66 ◽  
Author(s):  
Arcady Zhukov ◽  
Margarita Churyukanova ◽  
Lorena Gonzalez-Legarreta ◽  
Ahmed Talaat ◽  
Valentina Zhukova ◽  
...  
Keyword(s):  
Heat Capacity ◽  
Hysteresis Loops ◽  
Magnetic Behaviour ◽  
Soft Magnetic ◽  
Magnetoelastic Anisotropy ◽  
Thermal Expansion Coefficients ◽  
Magnetoelastic Energy ◽  
Expansion Coefficients ◽  
The Difference ◽  
Magneto Resistance

We studied the effect ofthe magnetoelastic ansitropy on properties of nanostructured glass-coated microwires with soft magnetic behaviour (Finemet-type microwires of Fe70.8Cu1Nb3.1Si14.5B10.6, Fe71.8Cu1Nb3.1Si15B9.1 and Fe73.8Cu1Nb3.1Si13B9.1 compositions) and with granular structure (Cu based Co-Cu microwires). The magnetoelastic energy originated from the difference in thermal expansion coefficients of the glass and metallic alloy during the microwires fabrication, affected the hysteresis loops, coercivity and heat capacity of Finemet-type microwires. Hysteresis loops of all as-prepared microwires showed rectangular shape, typical for Fe-rich microwires. As expected, coercivity, HC, of as-prepared microwires increases with decreasing of the ratio ρ defined as the ratio between the metallic nucleus diameter, d to total microwire diameter, D. On the other hand we observed change of heat capacity in microwires with different ratio ρ. In the case of Co-Cu microwires ρ- ratio affected the structure and the giant magneto-resistance of obtained microwires.

Soft Magnetic Properties and Microstructures for the Fe Based Sputtered Films with High Bs

1991 ◽  
Vol 232 ◽  
Author(s):  
Migaku Takahashi ◽  
T. Shimatsu
Keyword(s):  
Magnetic Anisotropy ◽  
Magnetocrystalline Anisotropy ◽  
Film Plane ◽  
Initial Permeability ◽  
Physical Origin ◽  
Soft Magnetic ◽  
Magnetic Anisotropy Energy ◽  
Local Anisotropy ◽  
Sputtered Films ◽  
Sufficient Reduction

ABSTRACTPhysical origin of high initial permeability, μi, in Fe based films with large magnetocrystalline anisotropy and magnetostriction is systematically discussed in connection with the microstructure of the films. In order to decrease the local anisotropy fluctuation to determine μi in these films, decrease of effective magnetic anisotropy, Ueff, of each grain mainly caused by the sufficient reduction of grain size is required. Induced uniaxial magnetic anisotropy energy, Ku, in film plane plays an important role to decrease Ueff through the micromagnetic interaction. The ratio of Ueff /Ku proposed as the important key to analyse the magnetization process. The dependence of μi Ku is classified concerning for Ueff/Ku.

scholarly journals Development of Magnetic Microwires for Magnetic Sensor Applications

Sensors ◽  
2019 ◽  
Vol 19 (21) ◽  
pp. 4767 ◽  
Author(s):  
Valentina Zhukova ◽  
Paula Corte-Leon ◽  
Mihail Ipatov ◽  
Juan Maria Blanco ◽  
Lorena Gonzalez-Legarreta ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Hysteresis Loops ◽  
Magnetic Sensor ◽  
Internal Stresses ◽  
Soft Magnetic ◽  
Magnetoelastic Anisotropy ◽  
Sensor Applications ◽  
Gmi Effect ◽  
Magnetic Softness ◽  
Magnetic Wires

Thin magnetic wires can present excellent soft magnetic properties (with coercivities up to 4 A/m), Giant Magneto-impedance effect, GMI, or rectangular hysteresis loops combined with quite fast domain wall, DW, propagation. In this paper we overview the magnetic properties of thin magnetic wires and post-processing allowing optimization of their magnetic properties for magnetic sensor applications. We concluded that the GMI effect, magnetic softness or DW dynamics of microwires can be tailored by controlling the magnetoelastic anisotropy of as-prepared microwires or controlling their internal stresses and domain structure by appropriate thermal treatment.

scholarly journals Optimization of magnetic properties and GMI effect of Thin Co-rich Microwires for GMI Microsensors

Sensors ◽  
2020 ◽  
Vol 20 (6) ◽  
pp. 1558 ◽  
Author(s):  
Lorena Gonzalez-Legarreta ◽  
Paula Corte-Leon ◽  
Valentina Zhukova ◽  
Mihail Ipatov ◽  
Juan Maria Blanco ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Magnetic Anisotropy ◽  
Hysteresis Loops ◽  
Transverse Magnetic ◽  
Wide Frequency Range ◽  
Soft Magnetic ◽  
Giant Magnetoimpedance ◽  
Giant Magnetoimpedance Effect ◽  
Annealing Temperatures ◽  
High Annealing

Magnetic microwires can present excellent soft magnetic properties and a giant magnetoimpedance effect. In this paper, we present our last results on the effect of postprocessing allowing optimization of the magnetoimpedance effect in Co-rich microwires suitable for magnetic microsensor applications. Giant magnetoimpedance effect improvement was achieved either by annealing or stress-annealing. Annealed Co-rich presents rectangular hysteresis loops. However, an improvement in magnetoimpedance ratio is observed at fairly high annealing temperatures over a wide frequency range. Application of stress during annealing at moderate values of annealing temperatures and stress allows for a remarkable decrease in coercivity and increase in squareness ratio and further giant magnetoimpedance effect improvement. Stress-annealing, carried out at sufficiently high temperatures and/or stress allowed induction of transverse magnetic anisotropy, as well as magnetoimpedance effect improvement. Enhanced magnetoimpedance ratio values for annealed and stress-annealed samples and frequency dependence of the magnetoimpedance are discussed in terms of the radial distribution of the magnetic anisotropy. Accordingly, we demonstrated that the giant magnetoimpedance effect of Co-rich microwires can be tailored by controlling the magnetic anisotropy of Co-rich microwires, using appropriate thermal treatment.

scholarly journals Application Potential of Nanocrystalline Ribbons Still Pending

2010 ◽  
Vol 61 (5) ◽  
pp. 264-270
Author(s):  
Pavol Butvin ◽  
Beata Butvinová ◽  
Peter Švec ◽  
Jozef Sitek
Keyword(s):  
Magnetic Anisotropy ◽  
Domain Structure ◽  
Power Loss ◽  
Hysteresis Loops ◽  
Wide Spread ◽  
Soft Magnetic ◽  
Principal Reason ◽  
Macroscopic Stress ◽  
Application Potential

Application Potential of Nanocrystalline Ribbons Still Pending Nanocrystalline soft-magnetic ribbons promised a wide-spread practical use when introduced at the beginning of nineties. After 20 years of extensive research there are still unclear material problems which are thought to be the principal reason why these materials show but marginal use. Poorly controllable magnetic anisotropy due to spontaneous intrinsic macroscopic stress that comes from an inevitable heterogeneity of the ribbon materials is pointed to in this work. Certain stress-based mechanisms are shown to induce the unintended anisotropy in the already familiar Finemets as well as in the newer Hitperms. Hysteresis loops, domain structure and power loss is used to reveal the anisotropy consequences and particular connected but still unanswered questions are pinpointed.

Magnetic Properties of Fe-Co Films with Tuneable In-Plane Uniaxial Anisotropy Prepared by Electrodeposition

2010 ◽  
Vol 160-162 ◽  
pp. 951-956
Author(s):  
Xu Yang ◽  
Lu Qian Gong ◽  
Liang Qiao ◽  
Tao Wang ◽  
Fa Shen Li
Keyword(s):  
Magnetic Field ◽  
Magnetic Anisotropy ◽  
Uniaxial Anisotropy ◽  
Anisotropy Field ◽  
Magnetic Films ◽  
Film Plane ◽  
Electrolyte Temperature ◽  
Soft Magnetic ◽  
Conductive Glass ◽  
Fe Content

Fe-Co soft magnetic films with tuneable in-plane uniaxial anisotropy were successfully electrodeposited onto ITO conductive glass. The influence of composition and electrolyte temperature on in-plane magnetic anisotropy field was investigated. Our results show that the in-plane uniaxial anisotropy can be induced by a magnetic field applied in the film plane during electrodeposition. Fe-Co films with various Fe content in the range from 35 at.% to 53 at.% were obtained and the magnetic anisotropy field was very sensitive to the composition. Moreover, the influence of electrolyte temperature on magnetic anisotropy field was investigated and it was found that the in-plane uniaxial anisotropy field can be tuned by varying the electrolyte temperature from 5 to 40 oC.

Recent Research on the Magnetoimpedance Effect in Co-Based Amorphous Ribbons

2013 ◽  
Vol 646 ◽  
pp. 222-227
Author(s):  
Lorena Gonzalez-Legarreta ◽  
V.M. Prida ◽  
Blanca Hernando ◽  
Mihail Ipatov ◽  
Valentina Zhukova ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Magnetic Anisotropy ◽  
Axial Magnetic Field ◽  
Anisotropy Field ◽  
Transverse Magnetic ◽  
Fabrication Process ◽  
Frequency Range ◽  
Soft Magnetic ◽  
Amorphous Ribbons ◽  
Current Annealing

We report the recent results obtained on the magnetoimpedance (MI) response in several near-zero magnetostriction Co-based amorphous ribbons with different width, and different transverse magnetic anisotropy (developed during the fabrication process or processing after production by the current annealing technique) in the frequency range of 10 MHz – 3.5 GHz. The evolution of the maximum of MI with the axial magnetic field, ascribed to the anisotropy field, as a function of the frequency provides useful information on the soft magnetic character of the ribbons.

Magnetic Anisotropy of Co-Nanostructures Embedded in Matrices with Different Pores Size and Morphology

2015 ◽  
Vol 233-234 ◽  
pp. 583-586 ◽  
Author(s):  
Elena Denisova ◽  
Lidia Chekanova ◽  
Rauf Iskhakov ◽  
Sergey Komogortsev ◽  
Ivan Nemtsev ◽  
...  
Keyword(s):  
Composite Materials ◽  
Magnetic Anisotropy ◽  
Anisotropy Field ◽  
X Ray Diffraction ◽  
Local Anisotropy ◽  
Polycarbonate Membrane ◽  
Crystalline Anisotropy ◽  
P Content ◽  
Polycarbonate Membranes ◽  
Size And Morphology

Composite materials with Co (P) particles embedded into pores of silica and track etched polycarbonate membranes were fabricated by an electroless reduction. The magnetic and structural properties of the composite materials are characterized by scanning electron microscopy, X-ray diffraction, and vibrating sample magnetometer. The macroscopic and local magnetic anisotropy of the Co (P) particles electroless deposited in the pores of the polycarbonate membrane and silica is studied. The composite materials with linear pores exhibit uniaxial magnetic anisotropy. The easy axis lies along the Co (P) rods, the shape anisotropy dominates over the intrinsic crystalline anisotropy. Information on local anisotropy field and the grain size was obtained from investigation of approach to saturation magnetization law. The local anisotropy field for all the samples depends on P content. For Co (P) rods the local anisotropy value is also determined by nominal pore sizes. It was found that the investigated Co (P) rods is nanocrystalline. The effects of different pores morphology on the FMR-spectra characteristics are studied.

scholarly journals Simulating the Hysteretic Characteristics of Hard Magnetic Materials Based on Nd2Fe14B and Ce2Fe14B Intermetallics

Crystals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 518 ◽  
Author(s):  
Natalia B. Kolchugina ◽  
Mark V. Zheleznyi ◽  
Aleksandr G. Savchenko ◽  
Vladimir P. Menushenkov ◽  
Gennadii S. Burkhanov ◽  
...  
Keyword(s):  
Magnetic Anisotropy ◽  
Magnetic Materials ◽  
Permanent Magnets ◽  
Mixed Valence ◽  
Hysteresis Loops ◽  
Anisotropy Field ◽  
Spin Reorientation ◽  
Cost Ratio ◽  
Hard Magnetic Materials ◽  
Negative Effect

The Ce2Fe14B intermetallic, like Nd2Fe14B, has the tetragonal Nd2Fe14B-type structure (space group P42/mnm), in which Ce ions have a mixed-valence state characterized by the coexistence of trivalent 4f1 and tetravalent 4f0 electron states. Despite the fact that the saturation magnetization, magnetic anisotropy field, and Curie temperature of the Ce2Fe14B intermetallic are substantially lower than those of Nd2Fe14B and Pr2Fe14B, Ce2Fe14B retains the capacity of being able to be used in the manufacturing of rare-earth permanent magnets. Moreover, at low temperatures, the anisotropy field of Се2Fe14B is higher than that of Nd2Fe14B, and Се2Fe14B does not undergo the spin-reorientation transition. In this respect, studies of (Nd, Ce)-Fe-B alloys, which are intended for the improvement of the service characteristics-to-cost ratio, are very relevant. A model and algorithm for calculating the hysteresis loops of uniaxial hard magnetic materials with allowance for the K1 and K2 (K2 > 0 and K1 > 0 and K1 < 0) magnetic anisotropy constants were developed and allowed us to obtain data on their effect on the parameters of hysteresis loops for a wide temperature range (0–300 K). The simulation and analysis of hysteresis loops of the quasi-ternary intermetallics (Nd1−хСех)2Fe14B (х = 0–1) was performed. Results of the simulation indicate that the alloying of the Nd2Fe14B intermetallic with Ce to x = 0.94 (1) does not completely eliminate the negative effect of spin-reorientation phase transition on the residual magnetization of the (Nd1−хCeх)2Fe14B intermetallic and (2) slightly decreases the slope of magnetization reversal curve.

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