Fig. 1. XRD patterns of (a) pure (Ni_0.5Zn_0.5)Fe₂O₄ powders, (b) 25 wt% ceramics, (c) 50 wt% ceramics, (d) 72 wt% ceramics, and (e) pure BaTiO₃ powders. All the ceramics are sintered at 1200  C for 7 h, while the pure (Ni_0.5Zn_0.5)Fe₂O₄ and BaTiO₃ powders are sintered at 1200  C for 2 h.

Fig. 2. XRD patterns of 72 wt% ceramics sintered at different temperatures of (a) 1000, (b) 1200, (c) 1220, and (d) 1230  C for 7 h.

Fig. 3. SEM micrographs of (a) 25, (b) 50, and (c) 72 wt% ceramics sintered at 1200  C for 7 h.

Fig. 4. Surface morphologies of 72 wt% ceramics sintered at (a) 1000, (b) 1200, (c) 1220, and (d) 1230  C for 7 h.

Fig. 5. DC electric resistivities of 25, 50, and 72 wt% ceramics as a function of sintering temperature.

Fig. 6. (a) Magnetization–magnetic field hysteresis loops, (b) saturation magnetizations, and coercive fields of 25, 50, and 72 wt% ceramics sintered at 1200  C.

Fig. 7. Frequency dependences of (a) real and (b) imaginary relative permeabilities of 25, 50, and 72 wt% ceramics sintered at 1200  C, together with pure (Ni_0.5Zn_0.5)Fe₂O₄ ferrite ceramics sintered at 1200  C.

Fig. 8. Polarization–electric field hysteresis loop of 72 wt% ceramics sintered at (a)1200 and (b) 1220  C.

Fig. 9. (a) Temperature dependences of relative permittivity at different frequencies of 1 kHz to 1 MHz for 72 wt% ceramics sintered at 1200  C, and (b) frequency dependences of relative permittivity and loss tangent of 72 wt% ceramics sintered at 1200  C.