Liknande böcker
Fabrication and Characterization of Zn Substituted Cu-Cr Ferrites : Fabrication and Characterization of Spinel Ferrites
Bok av Nazli Hina
This research project is aimed to fabricate and characterize zinc substituted copper chromium spinel ferrites of compositional scheme of ZnxCu1-x Cr0.5Fe1.5O4 (Where x=0, 0.2, 0.4, 0.6, 0.8) prepared by powder metallurgical methods using 99.99% commercially available ZnO, CuO, Cr2O3 and Fe2O3 as starting material. Accurately weigh powder were ball milled and calcined for 24 hours at 1100ºC. Then the calcined powders were homogenized using A-gate motor- pestle then sintered at 900oC for 10hours. Thermal, structural, morphological, elemental, magnetic, optical and dielectric properties were carried out using TGA-DTA, XRD, FESEM, EDS, VSM, FTIR and LCR meter respectively. TGA-DTA data provides the optimum temperature for the fabrication of spinel ferrites and later XRD micrographs reveal the formation of single phase spinel structure showing lattice parameters increases and x-ray and bulk density decreases as Zn content increases. FESEM shows the aggregated grain growth. FTIR spectra show two prominent bands in the range of 400-800 cm-1 which confirm the formation of spinel ferrites. The dielectric loss tangent and dielectric constant (e) decreases as frequency increases.