Studies on Electromagnetic Properties of Lithium Based Ferrimagnetic Spinel Oxides Prepared with Different Additives and Microwave Sintering

Soft ferrimagnetic spinel lithium based oxides were prepared with additives like V2O5 and Na2SiO3 and sintered with the efficient microwave sintering technique. Tetravalent metal ions substituents like Mn+4, Ti+4 were used to enhance the important properties like D. C. resistivity, saturation magnetization, permeability, hysteresis and dielectric behavior. The ferrites were sintered at different sintering temperatures viz., 900, 950 and 1000 degrees C for 10 min by microwave technique and by conventional technique at 1050 degrees C for 4h. X-ray diffraction (XRD) studied the structural behavior which confirmed the spinel characteristics, Scanning electron microscopy (SEM) and EDAX revealed the microstructural and elemental compositions respectively of the ferrites. The use of additives and the microwave sintering significantly influencing the microstructural behavior and subsequently on the electromagnetic properties could be observed. Studies of initial permeability and initial permeability loss found to remain nearly constant with change in frequency until at certain frequency they showed resonance behavior. The resonance frequency's dependence on the microstructures of the ferrites could be observed. Temperature dependence behavior of the dielectric parameters and the B-H loop traced from torroidal samples of the ferrites were studied.