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Project titleDevelopment and study of the physical properties of polymeric magnetic composite materials based on oxide ferrimagnets to ensure the electromagnetic compatibility of technical aids

Research area 09 - ENGINEERING SCIENCES, 09-205 - Development of new structural materials and coatings

KeywordsMagnetic composite materials, electromagnetic compatibility, hexagonal ferrites, spinel ferrites, magnetic permeability, saturation magnetization, magnetic field, electromagnetic field

Annotation
The aim of the project is to develop and study the structural and physical properties of magnetic polymer composite materials based on ferrimagnetic powders with the further formation of recommendations for their use as coatings absorbing side electromagnetic radiation. It is planned to synthesize and study the structure of microsized ferrite powders with a spinel-type crystal structure (Fe3O4, CoFe2O4, MnFe2O4), with a Y-type hexagonal crystal structure (Ba2Co2-xZnxFe12O22, Ba2Co2-xTixFe12O22, Ba2Ni2-xCuxFe12O22, x = 0; 0,5; 1; 1,5; 2). Based on these ferrites, polymeric magnetic composites absorbing electromagnetic radiation with a given structure of the magnetic phase will be manufactured. The structure in the material will be created by exposing the composite to a constant magnetic field in various directions during polymerization. The magnetic, structural and electrical properties of the fabricated composites will be investigated, including size properties, shape and surface effects, magnetization values, resonant frequencies, permeability and permittivity values, stoichiometry effects and their influence on the magnetic and structural properties of magnetic particles, important for assessing the possibility of their applications in space technology, microelectronics, computer technologies. Based on the data obtained, it is possible to design and manufacture magnetic composites with controlled properties, such as permeability, saturation magnetization, remanent magnetization, permittivity, and electrical conductivity. The main objective of the project is to develop methods for manufacturing new composite magnetic coatings based on ferrimagnets to absorb side electromagnetic radiation from electronic devices. To implement the project, two first-year graduate students of the Faculty of Radiophysics of Tomsk State University will be engaged: Kareva Katerina Valerievna, who has experience in conducting experiments on the study of structural and electrical characteristics, and Suraev Alexander Sergeevich, who is engaged in self-propagating high temperature synthesis (SHS) of oxide ferrimagnets, will be involved.

Expected results
As a result of the work, new magnetic composite materials can be obtained to ensure electromagnetic compatibility of modern electronic devices. As well as materials based on synthesized ferrites for spintronic devices and computer technology, for the point delivery of drugs in a living organism, can be created. Composites with high values of magnetic permeability can be manufactured, which will make it possible to replace the old element base, which has more bulky dimensions and greater weight. These limitations do not allow the use of existing components and elements of electronics in modern instrumentation. At the moment, scientists of the highest level are engaged in such research, which emphasizes the relevance and significance of the project for the scientific world. The results obtained will be published in scientific articles in high-ranking international journals included in the Web of Science and Scopus databases.

Annotation of the results obtained in 2022
During the reporting period, the following works were carried out: 1. The synthesis of oxide ferrimagnets with a hexagonal and cubic structure was carried out using standard ceramic technology, self-propagating high-temperature synthesis (SHS), the sol-gel method, and the mechanochemical method. 2. Studies of the structural characteristics and phase composition of the ferrites have been carried out. 3. Studies of the magnetic properties (saturation magnetization, remanent magnetization, coercive force, anisotropy field, ferromagnetic resonance method for hexaferrites, and according to the law of approach to saturation for ferrites with structural spinel) of the ferrite powders have been carried out. 4. The particle sizes of BaFe12O19 hexaferrites were determined from calculations of the coherent scattering region for all ferrite powder samples. 5. The temperature dependences of the initial permeability of the ferrite powders were measured. 6. The selection of a binder for the manufacture of samples of composite materials was carried out. 7. Samples of composite materials based on the ferrites were made. 8. Measurements of the reflection and transmission coefficients of composite materials were carried out. 9. The values of the initial permeability of samples of composite materials are determined. 10. The full spectra of the complex permeability have been reconstructed using the Kramers-Kronig relations. 11. The article was prepared and published the journal "Inventions". 12. The results of the work will be presented at the international conference "Uglerod: fundamentalnye problemy nauki, materialovedenie, tekhnologiya" (CFPMST 2023), June 7-9, 2023. The results obtained during the work: 1. BaFe12O19 hexaferrite samples synthesized according to a) standard ceramic technology, b) mechanochemical method, c) sol-gel method. 2. Samples of NiFe2O4 and CoFe2O4 ferrites with a spinel structure. 3. Samples of the system of Y-type hexaferrites Ba2Co2-xZnxFe12O22 (x = 0.0; 0.5; 1.0; 1.5), obtained by the method of self-propagating high-temperature synthesis without application of mechanical activation of powders of the initial oxides. 4. Samples of a system of Y-type hexaferrites Ba2Co2-xZnxFe12O22 (x = 0.0; 0.5; 1.0; 1.5) obtained by self-propagating high-temperature synthesis with application of preliminary mechanical activation of the initial oxides. 5. Samples of a system of Y-type hexaferrites Ba2Co2-xTixFe12O22 (x = 0,0; 0,5; 1,0; 1,5). 6. Samples of NiFe2O4 (S-type), Ba2NiCuFe12O22 (Y-type) and Ba3Co1,9Ti0,4Fe23,7O41 (Z-type) ferrites obtained by standard ceramic technology. 7. Hysteresis loops of the studied samples. 8. Pictures of scanning electron microscopy of the studied samples. 9. X-ray diffraction diagrams of the studied samples. 10. Samples of composite materials of the following compositions: a) 70 % wt Ba3Co1,9Ti0,4Fe23,7O41 + 30 % wt ED-20; b) 70 % wt NiFe2O4 + 30 % wt ED-20; c) 70 % wt BaFe12O19 + 30 % wt ED-20; d) 70 % wt Ba2CoZnFe12O22 + 30 % wt ED-20; e) 65 % wt + 34,95 % wt ED-20 + 0,5 % wt MWCNT; f) 75 % wt Ba2NiCuFe12O22 + 25 % wt ED-20. 11. Spectra of the real (μ') and imaginary (μ'') parts of the permeability; 12. Spectra of the real (ε') and imaginary (ε'') parts of the permittivity; 13. Initial values of the real and imaginary parts of the permeability and permittivity; 14. Reflection coefficient spectra of samples of composite materials. Links to information resources on the Internet dedicated to the project: Kompozity, sozdannye na RFF, budut luchshe pogloshchat' elektromagnitnoe izluchenie. ¬– URL: https://news.tsu.ru/news/v-tgu-sozdayut-materialy-sposobnye-pogloshchat-elektromagnitnoe-izluchenie/ (access date 04.05.2023)

Publications

1. Wagner D.V., Kareva K.V., Zhuravlev V.A., Dotsenko O.A., Minin R.V. Investigation of BaFe12O19 Hexaferrites Manufactured by Various Synthesis Methods Using a Developed Pulsed Magnetometer Inventions, Volume 8, Issue 1 (year - 2023) https://doi.org/10.3390/inventions8010026

2. - Композиты, созданные на РФФ, будут лучше поглощать электромагнитное излучение Сайт Томского государственного университета, 23.11.2022 (year - )