Dielectric and ferromagnetic properties of BaTiO_3/Ni_(0.93)Co_(0.02)Cu_(0.05)Fe_2O_4 composites

摘要

xBaTiO_3 + (1 - x)Ni_(0.93)Co_(0.02)Cu_(0.05)Fe_2O_4 (x = 0.5, 0.6, 0.7, 0.8) composites with ferroelectric-ferromagnetic characteristics were synthesized by the ceramic sintering technique. The presence of constituent phases in the composites was confirmed by X-ray diffraction studies. The average grain size was calculated by using a scanning electron micrograph. The dielectric characteristics were studied in the 100 kHz to 15 MHz. The dielectric constant changed higher with ferroelectric content increasing; and it was constant in this frequency range. The relation of dielectric constant with temperature was researched at 1, 10, 100 kHz. The Curie temperature would be higher with frequency increasing. The hysteresis behavior was studied to understand the magnetic properties such as saturation magnetization (M_s). The composites were a typical soft magnetic character with low coercive force. Both the ferroelectric and ferromagnetic phases preserve their basic properties in the bulk composite, thus these composites are good candidates as magnetoelectric materials.