Synthesis, magnetic properties and microstructure of Ni-Zn ferrite by sol-gel technique

In the study, the Ni-Zn ferrite powder of a Ni0.3Zn0.7Fe2O4 composition was synthesized by sol-gel route using metal acetates at low temperatures. Both the scanning electron microscope and X-ray diffraction analyses of various get samples heated at different temperatures were used to identify the reaction stages where the amorphous-gel-to-crystalline phase transition occurred. The electrical, magnetic and microstructural properties of the toroidal cores were studied. It was found that the initial permeability increased with a large frequency band (0.1-31.39 MHz) and the magnetic loss was small. The electrical resistivity was higher as compared to the ones which were obtained by the conventional process. Therefore, well-defined polycrystalline microstructure nickel-zinc ferrite and a short processing time of gel preparation have become the major achievements of this study. (c) 2006 Elsevier B.V. All rights reserved.