Ferroelectric and piezoelectric properties of (Bi1/2K1/2)TiO3 ceramics fabricated by hot-pressing method

Abstract

Bismuth potassium titanate, (Bi1/2K1/2)TiO3 (BKT), ceramics were prepared by the hot-pressing (HP) method without dopant and with dopants of Bi2O3, La2O3 and MnCO3. The relative density of BKT ceramics hot-pressed at 1,060 and 1,080 °C (hereafter abbreviated to BKT-HP1060°C and BKT-HP1080°C) and x mass% Bi2O3, La2O3 and MnCO3 doped BKT ceramics hot-pressed at 1,060 °C (hereafter abbreviated as BKTBix; x = 0.1–0.6, BKTLax; x = 0.1–0.6 and BKTMnx; x = 0.1–0.3) were all higher than 97%. In this study, the ferroelectric properties of BKT ceramics were successfully obtained, and the remanent polarization P r and coercive field E c of BKT-HP1080°C were 22.2 μC/cm2 and 52.5 kV/cm, respectively. A small amount of La tends to increase P r, and the P r of BKTLa0.1 was 19.2 μC/cm2. The piezoelectricities were improved to optimize poling conditions, and the electromechanical coupling factor k 33 and piezoelectric constant d 33 of BKT-HP1080°C were 0.34 and 82.8 pC/N, respectively.