Nickel-substituted Lithium-Zinc-Manganese Ferritefor the Suppression of Radiated Emission Noise

Nickel-substituted lithium-zinc-manganese ferrite of the composition,  Li0.25-x/4 Zn0.5-x/2NixMn 0.1Fe2.15-x/4O4 where x = 0, 0.1, 0.2, 0.3, 0.4, 0.5 have been investigated for electromagnetic interference(EMI)  suppression to meet the EMI standards. Various compositions were prepared by theconventional ceramic technique using mixed oxides. The ferrites were characterised for theirstructural, electrical, and magnetic, properties. The ferrites were found to posses high saturationmagnetisation, permeability, Curie temperature and resistivity, which are the desirablecharacteristics for noise-suppression application. The operating frequency of the ferrite rangedfrom 1 MHz–700 MHz, which is high enough for absorbing the electrical fast transients andradiated emission noise suppression as shown for three devices–currency counting machine,energy meter and dc-dc converter where the radiated emission noise  is suppressed from 10 dBto 20 dB. In energy meter where the electrical fast transients (EFTs) are suppressed up to 5.5kV, 4.5 kV, 3.5 kV, 2.8 kV, 1.6 kV, and 1.2 kV with composition x = 0, 0.1, 0.2, 0.3, 0.4, 0.5, respectively.This material has tremendous scope of application in military equipment  to comply the EMIrequirements of the military standards

Effect of LiTiMg ferrite as substrate for linear array of equilateral triangular microstrip patches under external magnetic field

53-56An analysis of a linear array of four microstrip triangular patches modeled on LiTiMg ferrite has been carried out. Here, polycrystalline LiTiMg ferrite, which is synthesized by the solid state reaction technique (SSRT), has been used as a substrate. The comparison of radiation pattern and some other parameters when the antenna array is biased, perpendicularly with varying magnetic field, or unbiased has been presented in this paper. The results obtained are quite different in comparison to other tested ferrites like LiTi and LiTiZn. The results suggest that the proposed antenna will be useful for scanning purpose in defense systems. The electric and magnetic properties of ferrite have also been tested and presented

A TEM study on lithium zinc ferrite thin films and the microstructure correlation with the magnetic properties

Sputtered lithium zinc ferrite films were studied using transmission electron microscopy to investigate the microstructure morphology and its correlation with the observed magnetic properties as a function of annealing temperature and time. The present study showed that the films contain nanocrystallites. The observed magnetic order in the films is because of inter granular coupling through low angle grain boundaries. The anomalous magnetic properties observed earlier in these films can be explained on the basis of the presence of large grain boundary volume.© Elsevie