High-power piezoelectric characteristics of textured bismuth layer structured ferroelectric ceramics

The high-power piezoelectric characteristics in (001) oriented ceramics of bismuth layer structured fer-roelectrics (BLSF), SrBi₂Nb₂O₉ (SBN), (Bi,La)₄Ti₃O₂ (BLT), and CaBi₄Ti₄Oi₅ (CBT), were studied by a constant voltage driving method. These textured ceramics were fabricated by a templated grain growth (TGG) method, and their Lotgering factors were 95%, 97%, and 99%, respectively. The vibration velocities of the longitudinal mode (33-mode) increased proportionally to an applied electric field up to 2.5 m/s in these textured BLSF ceramics, although, the vibration velocity of the 33-mode was saturated at more than 1.0 m/s in the Pb(Mn,Nb)O₃-PZT ceramics. The resonant frequencies were constant up to the vibration velocity of 2.5 m/s in the SBN and CBT textured ceramics; however, the resonant frequency decreased with increasing over the vibration velocity of 1.5 m/s in the BLT textured ceramics. The dissipation power density of the BLT was almost the same as that of the Pb(Mn,Nb)O₃-PZT ceramics. However, the dissipation power densities of the SBN and CBT were lower than those of the BLT and Pb(Mn,Nb)O₃-PZT ceramics. The textured SBN and CBT ceramics are good candidates for high-power piezoelectric applications.