Electric field and temperature dependent ferroelectric behavior of Bi0.5Na0.5TiO3-Bi0.5K0.5TiO3-BiMg0.5Ti0.5O3 piezoceramics

The ferroelectric (FE) hysteresis behavior of solid state synthesized 72.5Bi(0.5)Na(0.5)TiO(3)-22.5Bi(0.5)K(0.5)TiO(3)-5BiMg(0.5)Ti(0.5)O(3) ceramics were studied at different electric field amplitudes (E-0) and temperatures (T). The three-stage dynamic behavior was identified on the basis of hysteresis shape in different E-0 regions (stage I: 0 < E-0 < 8.7 kV/cm, stage II: 8.7 < E-0 < 39.2 kV/cm, stage III: 39.2 < E-0 < 68 kV/cm). The variation in electro-strain (S) with E-0 also support the same and indicates a correlation between S and polarization (P), which was further confirmed by dS/dP vs E-0 and S vs P-2 plot. The T dependent FE and electro-strain loops was investigated at 55 kV/cm in 25 degrees C-180 degrees C. On the basis of its hysteresis shape, the FE loops were grouped into three T regimes, i.e., (i) 25 degrees C-70 degrees C (ii) 80 degrees C-120 degrees C and (iii) 130 degrees C-180 degrees C.