BaTiO3/CoFe2O4 particulate composites with large high frequency magnetoelectric response

The elastic constants of particulate composites are evaluated employing a theoretical cube-within-cube formation. Two new models of four and five components, respectively, formed by geometrical combination of three-component models existing in the literature, are used as Representative Volume Elements. Using the governing stress and strain equations of the proposed models, two new equations providing the static elastic and shear moduli of particulate composites are formulated. In order to obtain the dynamic elastic and shear moduli, the correspondence principle was applied successively to components connected in series and/or in parallel. The results estimated by the proposed models were compared with values evaluated from existing formulae in the literature, as well as with values obtained by tensile, dynamic, and ultrasonic experiments in epoxy/iron particulate composites. They were found to be close to values obtained by static and dynamic measurements and enough lower compared with values obtained from ultrasonic experiments. The latter is attributed to the high frequency of ultrasonics. Since measurements from ultrasonic's and from dynamic experiments depend on the frequency, the modulus of elasticity estimated by ultrasonic's is compared with that (storage modulus) estimated by dynamic experiments.

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Correlation between structural deformation and magnetoelectric response in (1−x) Pb(Zr0.52Ti0.48)O3–xNiFe1.9Mn0.1O4 particulate composites

Applied Physics Letters ◽

10.1063/1.2799261 ◽

2007 ◽

Vol 91 (16) ◽

pp. 162905 ◽

Cited By ~ 18

Author(s):

Rashed Adnan Islam ◽

Jiechao Jiang ◽

Feiming Bai ◽

Dwight Viehland ◽

Shashank Priya

Keyword(s):

Structural Deformation ◽

Particulate Composites ◽

Magnetoelectric Response

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Size-dependent magnetoelectric response of (Bi0.5Na0.5TiO3-Bi0.5K0.5TiO3)-(Ni0.8Zn0.2)Fe2O4 particulate composites

Ceramics International ◽

10.1016/j.ceramint.2017.11.151 ◽

2018 ◽

Vol 44 (4) ◽

pp. 3712-3717 ◽

Cited By ~ 4

Author(s):

Sheng Liu ◽

Shuoqing Yan ◽

Heng Luo ◽

Longhui He ◽

Jun He ◽

...

Keyword(s):

Particulate Composites ◽

Size Dependent ◽

Magnetoelectric Response

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Re-Design of Machine Tool Joint Components Based on Polymer Fillings for High-Speed Performance

Materials ◽

10.3390/ma14226913 ◽

2021 ◽

Vol 14 (22) ◽

pp. 6913

Author(s):

Zuzana Murčinková ◽

Pavel Adamčík ◽

Jozef Živčák

Keyword(s):

Acoustic Emission ◽

High Frequency ◽

High Speed ◽

Dynamic Properties ◽

Hybrid Structure ◽

Particulate Composites ◽

High Frequency Signal ◽

Structural Modifications ◽

Speed Performance

In this paper, we report the results of an experimental study of a re-design approach using filling polymers and particulate composites with a polymer matrix, thus creating a macroscopic hybrid structure. The re-design is focused on the joint of a textile machine. It is a re-design of already existing machine parts of a joint in order to increase the damping of components, reduce the amplitudes of high-frequency vibrations and acoustic emission for high-speed operation of textile rotors, and to compare individual structural modifications of the rotor housing body and absorber of high-speed textile rotor in a spinning unit with respect to dynamic properties of that measured mechanical system. The experiments included a bump test, determination of logarithmic decrement, measurement of vibration acceleration, a wavelet analysis, and measurement of acoustic emission. When excited by high frequency signal amplitudes up to 5 g, the benefits of polymer filling were manifested by an approximately 50% reduction in amplitude vibrations, a 66% reduction in acoustic emission amplitude, and an 85% reduction of the maximum peak in the acoustic emission FFT spectrum. In the area above 10 g, the stiffness of the component dominated to reduce the magnitude of vibrations.

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Nonlinear magnetoelectric response of a Metglas/piezofiber laminate to a high-frequency bipolar AC magnetic field

Applied Physics Letters ◽

10.1063/1.4795307 ◽

2013 ◽

Vol 102 (10) ◽

pp. 102905 ◽

Cited By ~ 14

Author(s):

Ying Shen ◽

Junqi Gao ◽

Menghui Li ◽

Jiefang Li ◽

D. Viehland

Keyword(s):

Magnetic Field ◽

High Frequency ◽

Ac Magnetic Field ◽

Magnetoelectric Response

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The Microstructure of Steatite (Protoenstatite)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100118102 ◽

1985 ◽

Vol 43 ◽

pp. 236-237

Author(s):

W. E. Lee ◽

A. H. Heuer

Keyword(s):

High Frequency ◽

Glass Ceramics ◽

Magnesium Silicate ◽

Beam Current ◽

Glassy Matrix ◽

Angle Of Incidence ◽

X Ray ◽

Mechanical And Electrical Properties ◽

Argon Ions ◽

High Temperature Polymorph

IntroductionTraditional steatite ceramics, made by firing (vitrifying) hydrous magnesium silicate, have long been used as insulators for high frequency applications due to their excellent mechanical and electrical properties. Early x-ray and optical analysis of steatites showed that they were composed largely of protoenstatite (MgSiO3) in a glassy matrix. Recent studies of enstatite-containing glass ceramics have revived interest in the polymorphism of enstatite. Three polymorphs exist, two with orthorhombic and one with monoclinic symmetry (ortho, proto and clino enstatite, respectively). Steatite ceramics are of particular interest a they contain the normally unstable high-temperature polymorph, protoenstatite.Experimental3mm diameter discs cut from steatite rods (∼10” long and 0.5” dia.) were ground, polished, dimpled, and ion-thinned to electron transparency using 6KV Argon ions at a beam current of 1 x 10-3 A and a 12° angle of incidence. The discs were coated with carbon prior to TEM examination to minimize charging effects.

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Simulations of high-resolution images of amorphous silicon films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010014419x ◽

1986 ◽

Vol 44 ◽

pp. 544-545

Author(s):

G. Y. Fan ◽

J. M. Cowley

Keyword(s):

Electron Microscope ◽

High Frequency ◽

Fourier Transformation ◽

Amorphous Materials ◽

Low Frequency ◽

Chromatic Aberration ◽

Structure Information ◽

Frequency Components ◽

High Resolution Images ◽

Spatial Frequency Spectrum

It is well known that the structure information on the specimen is not always faithfully transferred through the electron microscope. Firstly, the spatial frequency spectrum is modulated by the transfer function (TF) at the focal plane. Secondly, the spectrum suffers high frequency cut-off by the aperture (or effectively damping terms such as chromatic aberration). While these do not have essential effect on imaging crystal periodicity as long as the low order Bragg spots are inside the aperture, although the contrast may be reversed, they may change the appearance of images of amorphous materials completely. Because the spectrum of amorphous materials is continuous, modulation of it emphasizes some components while weakening others. Especially the cut-off of high frequency components, which contribute to amorphous image just as strongly as low frequency components can have a fundamental effect. This can be illustrated through computer simulation. Imaging of a whitenoise object with an electron microscope without TF limitation gives Fig. 1a, which is obtained by Fourier transformation of a constant amplitude combined with random phases generated by computer.

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