Abstract:
Ni-Cu-Zn ferrites are well known technological magnetic material finding
applications in various electrical devices. The present work is focused on the
influence on electromagnetic and transport properties of Fe-deficient Ni-Cu-Zn
ferrites. These ferrite samples of composition (Ni0.28Cu0.10Zn0.62O)(Fe2O3)x-1 , where x = 0.00, 0.02, 0.04, 0.06 and 0.08 were prepared using the solid state reaction
technique. The phase identification was carried out by X-ray diffraction. The X-ray
diffraction analysis revealed that the samples crystallize in single phase cubic spinel
structure. A slight increase of Curie temperature (Tc) saturation magnetization (Ms)
and initial permeability µʹwith increase of Fe-deficient were observed. The
permeability spectrum with frequency follows the Snoek's limit. Sample with x =
0.00 sintered at 1100°C possess the maximum value of relative quality factor (RQF).
From the B-H loops, the remanance (Br) and coercive force (Hc) were determined.
Saturation induction (Bs) and Br/( Bs) are measured from low field B-H loops is found to
increase with increasing Fe-deficient up to x = 0.04 thereafter decrease. DC resistivity
increases with increasing Fe-deficient up to x = 0.06 and thereafter decrease. The
dielectric constant is found to decrease continuously with increasing frequency and
remains almost constant at higher frequency range. From hysteresis parameter it was
revealed that optimum soft magnetic properties corresponds to the composition with x
= 0.06 sintered at I 1000C having highest permeability, maximum induction, minimum
coercivity and hysteresis losses.
Description:
This thesis is submitted to the Department of Physics, Khulna University of Engineering & Technology in partial fulfillment of the requirements for the degree of Master of Philosophy in Physics, July 2013.
Cataloged from PDF Version of Thesis.
Includes bibliographical references (pages 105-112).