Magnetic Anisotropy Effects on Squareness Ratio of Nd–Fe–B Sintered Magnets With Different Coercivity

CoFeB nanotubes were fabricated by electroless plating in magnetic field using anodized aluminum oxide template, and the structural and magnetic properties of CoFeB nanotubes were investigated. It is found that some nano-scale particles form on the wall of nanotubes. Both coercivity ratio and squareness ratio of out-of-plane to in-plane are significantly changed by the applied magnetic field during electroless plating, which indicates that directional ordering in amorphous CoFeB nanotubes are achieved during electroless plating under magnetic field. The results show that the applied field impacts the magnetic anisotropy of amorphous nanotubes. The anisotropy is stronger with the magnitude of applied field increasing.

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Magnetic Anisotropy and Growth Texture in Co35Pd65 Films

MRS Proceedings ◽

10.1557/proc-475-149 ◽

1997 ◽

Vol 475 ◽

Cited By ~ 1

Author(s):

S. U. Jen ◽

J. Y. Huang ◽

K. B. Huang

Keyword(s):

Magnetic Anisotropy ◽

Saturation Magnetization ◽

Easy Axis ◽

Profile Analysis ◽

Surface Topology ◽

Perpendicular Anisotropy ◽

Atomic Force ◽

Squareness Ratio ◽

Out Of Plane ◽

Pd Alloy

ABSTRACTPd-rich Co-Pd alloy films are well known to exhibit perpendicular anisotropy. In this study, Co35Pd65 films were made by the vapor deposition method. The thickness of the films ranged from 80 to 2000 Å. Following measurements were carried out on each film sample: the impurities and alloy compositions were checked by Auger depth profile analysis (AES), the surface topology was mapped out by an atomic force microscope (AFM), the structural analysis was done by using the X-ray diffractometer (XRD), and the magnetic properties, such as magnetic anisotropy and saturation magnetization, were measured by a SQUID magnetometer and/or a MOKE (using the longitudinal or polar effect) apparatus. Magnetic quantities, such as the out-of-plane (either hard or easy axis) squareness ratio Mr/Ms, saturation magnetization Ms, and anisotropy energy Ku, are closely related to the structural properties, such as the degree of (111) texture, grain size D, mode of growth (nucleation texture or growth texture), and impurities in films. The emphasis is placed on the thickness dependence of these quantities, and the interrelationship among them.

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Development of Co-Rich Microwires with Graded Magnetic Anisotropy

Sensors ◽

10.3390/s22010187 ◽

2021 ◽

Vol 22 (1) ◽

pp. 187

Author(s):

Valentina Zhukova ◽

Paula Corte-Leon ◽

Juan Maria Blanco ◽

Mihail Ipatov ◽

Alvaro Gonzalez ◽

...

Keyword(s):

Temperature Gradient ◽

Magnetic Anisotropy ◽

Hysteresis Loop ◽

Domain Structure ◽

Variable Temperature ◽

Anisotropy Field ◽

Gradual Change ◽

Simple Route ◽

Squareness Ratio

In this paper, a gradual change in the hysteresis loop of Co-rich glass-coated microwire stress-annealed at variable temperature is observed. Such microwires annealed with a temperature gradient also present a variable squareness ratio and magnetic anisotropy field along the microwire’s length. The obtained graded anisotropy has been attributed to a gradual modification of the domain structure along the microwire originated by a counterbalance between shape, magnetoelastic, and induced magnetic anisotropies. Accordingly, we propose a rather simple route to design graded magnetic anisotropy in a magnetic microwire.

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TEM Study of Co/Pd and Co/Au Multilayers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100151015 ◽

1993 ◽

Vol 51 ◽

pp. 1036-1037

Author(s):

A.E.M. De Veirman ◽

F.J.G. Hakkens ◽

W.M.J. Coene ◽

F.J.A. den Broeder

Keyword(s):

Magnetic Anisotropy ◽

Ion Beam ◽

Perpendicular Magnetic Anisotropy ◽

Optical Recording ◽

Magnetic Multilayer ◽

Ion Beam Sputtering ◽

Cross Sectional ◽

Transmission Electron ◽

Beam Sputtering ◽

Substrate Temperatures

There is currently great interest in magnetic multilayer (ML) thin films (see e.g.), because they display some interesting magnetic properties. Co/Pd and Co/Au ML systems exhibit perpendicular magnetic anisotropy below certain Co layer thicknesses, which makes them candidates for applications in the field of magneto-optical recording. It has been found that the magnetic anisotropy of a particular system strongly depends on the preparation method (vapour deposition, sputtering, ion beam sputtering) as well as on the substrate, underlayer and deposition temperature. In order to get a better understanding of the correlation between microstructure and properties a thorough cross-sectional transmission electron microscopy (XTEM) study of vapour deposited Co/Pd and Co/Au (111) MLs was undertaken (for more detailed results see ref.).The Co/Pd films (with fixed Pd thickness of 2.2 nm) were deposited on mica substrates at substrate temperatures Ts of 20°C and 200°C, after prior deposition of a 100 nm Pd underlayer at 450°C.

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