Fabrication of 0.7BaTiO3-0.3Ni0.7Zn0.3Fe2O4 Multiferroic Composite Ceramics Prepared by the Solid-State Combustion Technique

Lead-free multiferroic composite ceramics of 0.7BaTiO(3)-0.3Ni(0.7)Zn(0.3)Fe(2)O(4) (BT-NZF) were prepared by the solid-state combustion technique. The BT and NZF powders were calcined in the range of 1100 to 1200 degrees C for 4 h and 900 to 1100 degrees C for 2 h, respectively. Afterward, BT-NZF composite ceramics were sintered between 1100 and 1250 degrees C for 4 h. The effect of the firing temperature on the phase formation, microstructure, electrical, and magnetic properties of BT-NZF composite ceramics was investigated. X-ray diffraction of BT and NFZ powders showed the highest purity phase were prepared the calcination temperatures of 1100 and 1050 degrees C, respectively. The BT-NZF composite ceramics exhibited coexisting tetragonal perovskite and cubic spinel phases. The maximum density of 5.85 g/cm(3) was obtained when sintering the composite ceramics at 1125 degrees C. The dielectric constant at room temperature increased with increased sintering temperature. The hysteresis loops showed leakage current in all samples. Ferromagnetic properties showed the highest M-s similar to 24.56 emu/g measured under a magnetic field of 10,000 Oe from the sample sintered at 1150 degrees C.