Piezoelectric Properties of Bismuth Layer-Structured Ferroelectric SrBi_2Ta_2O_9-Bi_3TiTaO_9 Ceramics

摘要

Dielectric, ferroelectric and piezoelectric properties of SrBi_2Ta_2O_9 (SBTa) and Bi_3TiTaO_9 (BTT) solid solution system, that is, Sr_(x-1)Bi_(4-x)Ti_(2-x)Ta_xO_9 [SBTT2(x)] (1 <= x <= 2), were investigated. The Q_m and k_p were enhanced the maximum value of 13500 and 0.12, respectively, on the SBTT2(1.25) with poling conditions of E_p = 7-10 kV/mm, T_p= 300 deg C and t_p=7 min, respectively. This value is extremely high in piezoelectric ceramics. In the same poling conditions, Q_m of (33) and (15) vibration modes for SBTT2(1.25) were about 8800 and 6000. Temperature coefficients of the resonance frequency, TC-f_r, of SBTT2(1.25) were -82 ppm/deg C for (33) mode and -97 ppm/deg C for (15) mode, respectively.