CASPIAN JOURNAL
MANAGEMENT AND HIGH TECHNOLOGIES
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Read | Bulatov Marat F., Rybakov Alexey V. // Caspian journal : management and high technologies. — 2012. — №2. — pp. 108-114. |
Bulatov Marat F. - Sc.D. (Physics and Mathematics), Professor, Astrakhan State University, 414056, Russia, Astrakhan, 20a, Tatishchev st., bulatov_agu@mail.ru.
Rybakov Alexey V. - lecturer of department, Astrakhan State University, 414056, Astrakhan, 20a Tatishchev st., rybakov_alex@mail.ru.
W-type hexagonal strontium ferrites synthesized by using the cryochemical method. The main problems to preparing this compositions by traditionally ceramic method are difficult synthesis of single phase materials that the reason is neighborhood of different structure type in the phase diagram. As a source of salt for the preparation of the solution were chosen nitrates. Solution as a monodisperse stream of droplets subjected kryocrystallization and freeze-drying. The phase composition and crystal structure of the synthesized samples identified by X-ray diffraction. To study the microstructure we used scanning electron microscopy. It is shown that the formation of W-hexaferrite is possible in the entire range of compositions SrNixCo 2-xFe16O27 (x = 0.2, 0.4, 0.6, 0.8, 1). It was found that at a temperature of 1100–1200 °C lamellar particles hexaferrite are formed, which become larger with increasing temperature in the process of recrystallization. The influence of synthesis conditions on the size and morphology of the particles in the powders are installed. Measured lattice parameters of samples and set their dependence on chemical composition.
Key words: hexaferrites,cryochemical method,scanning electronic microscopy,microstructure,freeze-drying,X-ray diffraction