Kinetics of Structural Changes in Strontium Hexa-Ferrite Powder during Milling in Beater Mill

Abstract:

The paper presents the results of experimental studies of strontium hexa-ferrite average particle size and structural characteristics changes during milling process. Coarse strontium hexaferrite was milled in beater mill, without and with electromagnetic effect. Electromagnetic effect was produced by constant and alternating gradient magnetic fields with mutually perpendicular induction lines. Particle sizes were measured by microscopic methods, and structural characteristics were calculated by processing of X-ray diffractograms. Diffraction studies showed that during milling process, both with and without electromagnetic effect, the most intensive changes of coherent scattering region (CSR) sizes, dislocation densities and relative deformation of particulate material occur at earlier stage of milling. At this stage the speed of average particle size decrease is maximal. At later stage both average particle size and structural characteristic changes correlate and have asymptotic character.

• Periodical: Materials Science Forum (Volume 989)
• Pages: 199-203
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.989.199
• Online since: May 2020
• Authors: Ivan N. Egorov*, Nikolay Ya. Egorov, Viktor P. Kryzhanovsky
• Keywords: Fluidized Bed, Magnetic Materials, Microstructure, Milling, Strontium Hexa-Ferrite

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