INFLUENCE OF Ni/Zn RATIO VARIATION ON STRUCTURAL AND MAGNETIC PROPERTIES OF NiZn FERRITES

Elemír Ušák - Mariana Ušáková

   Pure single phase polycrystalline NiZn ferrite materials with the chemical composition Ni_xZn_1-xFe₂O₄, where x = 0.30, 0.33, 0.36, 0.42 and 0.50 were prepared by solid state reaction with a slow cooling from the sintering temperature 1200°C for 6 hours. The in-fluence of Ni/Zn ratio in composition on structural and magnetic properties prepared ferrite samples was investigated. The struc-tural properties were analysed using by the X–ray diffraction method, the particle size and shape were studied using by the Scan-ning Electron Microscope. Low-frequency magnetic properties of prepared NiZn ferrites were determined from the measured mag-netisation curves. The results have confirmed known, a little bit surprising fact, that for x > 0.3 the addition of ferromagnetic metal (Ni) into the chemical composition deteriorates some magnetic properties (especially the permeability, coercivity, etc), meanwhile the Curie temperature increases.

Keywords: ferrites, structural properties, magnetic properties

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