Microstructure and Magnetic Properties of Sr۲Co۱.۷Mg۰.۳Fe۱۱.۲ Hexaferrite Synthesized by Auto-Combustion Sol-Gel Method

A single phased Y-type hexagonal ferrite Sr۲Co۱.۷Mg۰.۳Fe۱۱.۲Sn۰.۴Zn۰.۴O۲۲ was synthesized by the sol–gel auto combustion method. Structural and magnetic properties of this composition of Y-type hexagonal ferrite have been investigated. The X-ray diffraction (XRD) patterns confirm single phase Y-type hexagonal ferrite and various parameters such as lattice constants and cell volume have been calculated from XRD data. The morphology and size distribution of the particles have been studied using high resolution field emission scanning electron microscopy (FESEM). The Fourier transform infrared (FTIR) spectra show the characteristics absorption ferrite peaks of the sintered sample. The thermo gravimetric (TG) and differential thermal analysis (DTA) are used to study the systematic weight loss and subsequent transformation during heat treatment. Magnetic properties were determined using a vibrating sample magnetometer (VSM). Single phase Y-type ferrite powders were obtained after calcinations at ۱۰۰۰ °C. The XRD results showed that the crystallite size of particles is ۴۴ nm. The microstructures of the pure powders appeared as a hexagonal platelet-like structure. The saturation magnetization (Ms) and the coercivity (Hc) of the samples were in the range, ۲۶.۵۸–۵۰.۴۲ emu/g and ۵۴۶-۱۱۰۸ Oe, respectively. The effect of the heat treatment temperature was to increase the magnetization, following a slight coercivity decrease due to replacing of intermediate phases by single Y-type hexaferrite. Which it can be used as soft magnetic materials for multilayer inductors for high frequency applications.

Keywords:

Y , type hexaferrite , sol , gel auto combustion , Magnetic properties , calcination temperature