GRAIN SIZE DEPENDENT DIELECTRIC AND MAGNETIC PROPERTIES OF (Y) NCCF+(1 - Y) BTO PARTICULATE COMPOSITES

摘要

The particulate composites with general formula (y) Ni_(0.85)Cd_(0.1)Cu_(0.05)Fe_2O_4 + (1 - y)BaTiO_3, (0.0 < y < 1.0) were synthesized by conventional double sintering ceramic technique. The formation of cubic spinel structure in ferrite phase and tetragonal perovskite structure in ferroelectric phase was confirmed by X-ray diffraction (XRD) measurements. The surface morphology with average grain size of the composites was studied by SEM measurements. The study of variation of dielectric constant with frequency (20 Hz to 1MHz) shows dielectric dispersion behavior in the low frequency region and almost constant at high frequency region. The linear variation in a.c conductivity with frequency shows small polaron type of conduction mechanism in the composites. The vibrating sample magnetometer (VSM) was used to study the magnetic properties such as saturation magnetization and magnetic moment.