Russian Scientists Improve the Electromagnetic Properties of Materials for 5G Technologies
SUSU scientists continue to study barium hexaferrite. In a new experiment, specialists created material with very high properties of absorption of electromagnetic waves in comparison with those studied before and confirmed its features. An article on the study of the microwave properties of aluminum-substituted barium hexaferrite was published in one of the most prestigious journals of the first quartile, Journal of Alloys and Compounds.
Improvement of Electromagnetic Properties
Until recently, barium ferrites with a hexagonal structure were considered the ideal material for creating permanent magnets. However, now more and more often barium hexaferrite is considered as multiferroics, that is, materials with a double type of order—magnetic and electric. They can be employed, for example, in microwave devices. Hexaferrites are good at absorbing electromagnetic waves. Moreover, the properties of the materials depend on the concentration of ions in the material of chemical elements that replace iron ions.
Researchers of South Ural State University are constantly studying barium hexaferrite. They synthesize materials with various substitutions to examine their properties. Therefore, in the latter work, scandium ions were used to replace iron ions. Barium hexaferrite has demonstrated high wave absorption properties in the frequency range of 20-60 GHz. The obtained result opens up broad prospects for practical application, for example, in the field of 5G technologies.
Formerly, SUSU scientists have already studied the microwave properties of barium hexaferrite, but in the range of 23-50 GHz. The researchers used a material in which iron ions are replaced by titanium and aluminum ions. Such heterovalently substituted barium hexaferrite was synthesized at the Crystal Growth Laboratory.
"This study is part of a vast area of research into the effects of hexaferrite substitution on their structure and properties. It should be understood that various cations affect the properties of the initial matrix in diverse ways. We selected two that possess the other effect—titanium and aluminum. For each alloying element, it is significant to determine the value of the characteristics in the largest possible frequency range. And this demands the use of various sets of equipment. In this case, we are talking about the frequency range of 32-50 GHz. It was discovered that samples with a significant degree of substitution of aluminum possess the most superior properties of absorption of electromagnetic waves," commented Denis Vinnik, head of the Laboratory of Magnetic Oxide Materials from SUSU, professor.
New Materials Are Planned
The research was supported by the Russian Science Foundation, project No. 18-79-00154. To create hexaferrite and examine its features, scientists from two departments were involved—the SUSU School of Electronic Engineering and Computer Science and the Polytechnic Institute. The approach for examining the properties of new materials at microwave frequencies was developed by candidates of technical sciences, associate professors of the SUSU School of Economics Denis Klygach, and Maxim Vakhitov. They also took measurements and processed the results. The equipment for the experiment in the frequency range 32–50 GHz was provided by the Ural Federal University. The results obtained prove that this direction considers the prospect of research.
"Extending experiments in this area will allow us to model alternative materials with desired electrodynamic properties, for example, dielectric constant, magnetic constant, which will significantly reduce the time to develop such materials. Now work is underway to model the electrodynamic properties of composite materials, including those based on hexaferrite, in the given frequency ranges," Maxim Vakhitov told about further work.
The materials examined by scientists, demonstrating the excellent properties of absorption of electromagnetic waves, can be used to create cases and substrates for microwave devices (microwave) and to ensure the electromagnetic compatibility of electronic devices.
Research in the field of materials science is one of the three strategic directions for the development of scientific and academic activities of the South Ural State University along with the digital ecology industry.
SUSU is a participant in the 5-100 project, designed to increase the competitiveness of Russian universities among the world's leading research and academic centers.
More information:
doi.org/10.1016/j.jallcom.2019.152682
Provided by South Ural State University