National University of Science and Technology MISiS:

T. A. Bulatov

S. V. Ketov

V. P. Menushenkov

Yu. D. Yagodkin

Structural changes of strontium hexaferrite powders after milling in water and toluene and after subsequent annealing were studied using X−ray diffraction, Scanning Electron Microscopy and Laser diffraction. Also magnetic properties changes were studied. The coarse−grain powder milling leads to an abrupt decrease of its particles size and the average crystallite size as well as an increase of SrFe₁₂O₁₉ phase lattice microstrains. Saturation magnetization and remanence decrease after milling in both media. At the same time coercive force of milled powders changes insignificantly with increasing milling time. The subsequent annealing allowed us to increase the magnetic properties of the powder. The annealed powders are characterized by the following magnetic properties: μ₀Н_ci = 0,42÷0,49 T, μ₀I_r = 0,23÷0,24 T, (BH)_max = 8−9,6 kJ/m³.

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