Fabrication, structure and magnetic properties of nanocrystalline NiZn-ferrite by high-energy milling

Nanocrystalline NiZn-ferrite was fabricated by a high-energy milling method with Fe3O4+NiO+ZnO. The structure and magnetic properties of the milled powder were measured and analyzed. The results show that the grain possesses a single-phase NiZn-ferrite structure in a typical size of 10-50 nm. The magnetic measurement gives a typical value of the saturation magnetization of 45 emu/g and a coercivity of 367 Oe. Superparamagnetic behavior is not observed. The experiment reveals that a purer NiZn-ferrite material can be obtained after the milled powder is annealed at relatively low temperature of about 1000 °C. The mechanism and efficiency of the synthesis technique are also discussed in this paper.