Studying the physical properties of ferrite type life 5O8 prepared by using freeze-drying method.

number: 
797
إنجليزية
department: 
Degree: 
Imprint: 
Physics
Author: 
Mohammed Hussein Ali Al-Darud
Supervisor: 
Dr. Emad K. Al- Shakarchi
year: 
2002
Abstract:

Ferrite type (β-LiFe5O8 has been prepared by using Freeze-Drying Method (FDM), and the physical properties were studied through ; the X-ray Diffraction (XRD), Fourier Transfonn Infrared (FTIR), Scanning Electron Microscope (SEM) and Magnetization Measurement. The synthesis process of freeze drying method starts from mixing a suitable amount of Li2CO3 and FeC6H5O7.5H2O according to their atomic percentages, then the mixture dissolved in distilled water, then the solution sprayed in liquid nitrogen by using a glass spray system, and then the droplets were dried by using freeze drying system with high vacuum (10¹- -10-² mbar) and low temperature (-40°C), produce a fine homogenous powder undergoes to thermal treatment in two stages, first calcination process to evolve the CO2, C6H5O7.5H2O and O2 and second sintering process in order to forming the ferrite phase. Ultrafme powder with high homogeneity was produced by FDM and this powder was pressed with different shapes such as disk, and ring, this ring was produced by using a ring mold designed in this work. The disk and ring product was sintered at different sintering temperatures (Ts) (900, 950,980 and 1000 and 1050°C) for 48hour for each temperature. The aim of this project is satisfy most properties of LiFe5O8 which satisfied at p-LiFe5O8 phase, and the best sample product was at (TS=1000°C) according to the (XRD) , (FTIR), and magnetization Measurements. In this work we got (β-LiFe5O8 at (TS=1050°C) with many properties of it without volatile of Li ions ,this was satisfied because of using FDM.