Synthesis, characterization and magnetic properties of glass ceramics containing nanoparticles of both Ba-hexaferrite and Zn-ferrite

Differential thermal analysis, X-ray diffractometry and transmission electron microscopy were used to study the crystallization behavior of glass ribbons with a composition of 35% BaO, 35% Fe2O3, 20% B2O3 and 10% TiO2 (mol.%). Replacement of different amounts of BaO by ZnO was studied. Heat treatment was applied at both 700 and 1000 degrees C for 1 h with heating rate 3 degrees C/min. Both Ba-hexaferrite and Zn-ferrite, with crystallite size 2-7 nm, were detected by XRD and TEM. The magnetic properties of ribbons prepared via cooling the melts between steel rollers were measured with a vibrating sample magnetometer. Magnetization saturation (Ms) was increased by increasing ZnO, while coercivity (Hci) increased by increasing BaO. Partial replacement of Ba by Zn revealed preparation of samples contains both Zn ferrite and Ba hexaferrite which give wide range for engineering application. (C) 2013 Elsevier Ltd and Techna Group S.r.l. All rights reserved.