Microphotographs of Textured Polycrystalline Ceramic Sample of Ba3Co2Ti0.8Fe23.2O41 (Co2Z). Upper picture - larger crystalline grains are parallel to the (x0y) surface; the lower picture - the cross-section (100) surface.
This is at least the 4-scale magnetic medium.
This kind of heterogeneous media as well as the known few scale physics of magnetism along with apparent gaps between each scale homogeneous physics description and modeling had landed my attention as the area for scaling application using the Two-, Three and more Scale volumetric and surficial tools of the VAT.
Most of developed up to these days the magnetism multiscale hierarchical HSP-VAT advancements are not published and not presented in this section materials describing modeling, and experimental data, electrodynamics' properties of multiscale media of magnetic materials. Nevertheless, few of our published works would be constructive in terms of the principles and of priorities in this field.
This approach accounts for few levels of scaling in a multiphase material and introduces the parameters that characterize the morphology of the material.
It has also been used to describe acoustic and electrical properties of polymer composites, diffusion, electrical and magnetic properties of porous composites including some structures of ferrite media, as well as heat conductivity in HTSC ceramics.
Dielectric and magnetic properties of liquid-impregnated porous ferrite media were analyzed using Multiscaled Local, Non-local Hierarchical Scaled Physics-Volume Averaging Theory (HSP-VAT). Experimental procedures were designed for morphologies with tunable levels of reflection and absorption of electromagnetic waves. Tunability was accomplished by varying composition and concentration of the liquid, as well as by changing a temperature. Powders of ferrites with NFMR frequency in the microwave range were used as the porous magnetic media in a polymer housing. Water, alcohols, heptane, water-alcohol and hepatne-alcohol mixtures were used as liquid dielectrics to impregnate the porous media. Composition of the liquid, the liquid to solid phase ratio, the temperature and the shape of the polymer housing were varied. The spectra of microwave complex permittivity and the permeability of both dry and liquid-impregnated porous ferrite media were measured and the method of composite approximation was used to model the measured properties. In the case of ethyl alcohol or water-alcohol mixtures the real and imaginary permittivities exceed the upper Wiener boundary, indicating limited applicability of the composite approximation method for these systems.
It is still lacking of simulation efforts as long as of experiments, designed specifically for evidences of scaled properties and of inter-scale properties communications.
The modeling approach of HSP-VAT should substantially enhance our understanding of multi-scaled phenomena in ferromagnetics. Taking even the lower scales into considered simultaneously magnetic medium physics we will have the four- and more scales magnetism. Our ability to design and manufacture nanometric ferromagnet powders and ceramic processing, to predict thermo-mechanical, diffusive and electrical properties are dependent on having a correct theoretical description of the physical processes.
Among important features of the HSP-VAT those allowing it to recognize specific medium types and morphologies, lower-scale fluctuations of variables, cross-effects of different variable fluctuations, and interface variable fluctuations effects, etc. to be considered. It is not possible to include all these characteristics in current models using conventional theoretical approaches of one scale composite materials.
Thus, we are going to take the full advantage of using the HSP-VAT for conceptualizing,
theory, modeling, simulation, and design of
the multi-scale media of Magnetic Materials(MM).
This section is not the appropriate ground for exposition of the Ht Multiscaled Magnetism from A to Z, meanwhile the setting an impulse for curious student's minds as well as analyzing the current trends in the scaled description direction of Magnetism would be a worthwhile work.
From time to time we will be analyzing also the other publications that make allegations on multiscaling in Ferromagnetism (as well as in magnetism in general). Our few remarks on "pseudo-scaling" already have been posted in -
and in
Later on, in 2000s we finally developed for the other physics - Physics 2, the critical analysis with regard of reality of claims of orthodox physics on identity of Maxwell-Heaviside-Lorentz (all three scientists made the substantial input and at the same time - the substantial change in philosophy of electrodynamics) electrodynamics at sub-atomic and continuum scale. Only coefficients are different. We subjected this like a "law," by H.A.Lorentz primarily, to a thorough scrutiny and got to the conclusion - that it is not true:
Meanwhile, in the following sub-sections of this section we intend to portray few resent studies having contentions on multiscaling specifically in this physics field. In most of these works there is even no intention to provide the Averaging at all ?!
5) Travkin, V.S., Catton, I., and Ponomarenko, A.T., "Three Scale Hierarchical Modeling of Electrostatics and Electrodynamics in Porous Ferrites; Effective Dielectric Properties and Experiments," in Proc. 5th IUMRS-Int. Conf. Advansed Materials'99, Beijing, Vol. 2, p. 684, (1999)
9) Ponomarenko, A.T., Ryvkina, N.G., Kazantseva, N.E., Tchmutin, I.A., Shevchenko, V.G., Catton, I.,and Travkin, V.S., "Modeling of Electrodynamic Properties Control in Liquid-Impregnated Porous Ferrite Media", in Proc. SPIE Smart Structures and Materials 1999, Mathematics and Control in Smart Structures, V.V. Varadan, ed., Vol. 3667, pp. 785-796, (1999)
11) Travkin, V.S., Catton, I., Ponomarenko, A.T., Gridnev, S.A., Kalinin, Yu.E., Darinskiy, B.M., (2000), "Ferromagnetism in Scaled Hierarchical Materials. Wave Absorption on Micro- and Macroscale," in Proc. PIERS'2000: Progress in Electromagnetics Res. Symp., p. 1029, (2000)
16) Travkin, V.S., Catton, I., Ponomarenko, A.T., and Kalinin, Yu.E., "Bottom Up and Top Down, from Nano-Scale to Micro-Scale, Hierarchical Descriptions of Electrodynamic, Thermal and Magnetic Fields in Ferromagnets and HTSCs", in Proc. DOE 20th Symposium on Energy Engineering Sciences, Argonne National Laboratory, pp. 296-304, (2002)
17) Travkin, V. S. and Ponomarenko, A. T., "Electrodynamic Equations for Heterogeneous Media and Structures on the Length Scales of Their Constituents", Inorganic Materials, Vol. 40, Suppl. 2, pp. S128 - S144, (2004)
see the abstract via this link -
http://www.springerlink.com/app/home/... - "Electrodynamic equations for heterogeneous media..." ,
The latest our studies (of a few years) actually brought in the results summarizing many previous investigations (1988-2012) with regard of base for polyscale electrodynamics - as it is in the nature, and for the imbalance ground for magnetism, when electrons and atoms (molecules) magnetic moments, force fields could not be integrated, averaged via conventional orthodox Homogeneous physics (COHP) approaches, methods, and mathematics. Now our findings are available for scientists, engineers in the sections -
and
