Effects of sintering temperature and holding time on the microstructure and electric properties of Ba(Zr0.3Ti0.7)O3 ceramics

Abstract

Ba(Zr0.3Ti0.7)O3 (BZT) ceramics was prepared by using conventional solid state reaction. The effects of sintering temperature and holding time on the crystal structure, surface morphology, dielectric, ferroelectric and piezoelectric properties of the BZT ceramics were systematically investigated. X-ray diffraction (XRD) results confirm single cubic perovskite phase in all the sintered samples. Microstructure analysis using scanning electron microscopy (SEM) reveals that the grain sizes increase with increasing the sintering temperature. Dielectric spectroscopy performed in the range of 20Hz to 2MHz at room temperature shows that the dielectric constant increases with the sintering temperature and the dielectric constant of the BZT ceramics sintered at 1400?C for 8 h is around 11500. The ferroelectric hysteresis loops show that the coercive field decreases with the holding time, while the remnant polarization does not change obviously. The maximum strain is 0.023%for the sample sintered at 1400?C for 4 h. It is found that the maximum value of the direct piezoelectric coefficient (d33) of the BZT ceramics sintered at 1400?C for 8 h measured at room temperature is 36.7 pC/N.