Quenching effects on electrical properties of Cu-doped (Bi1/2Na1/2)TiO3-based solid solution ceramics

Quenching effects on electrical and piezoelectric properties were investigated for Cu-doped (Bi1/2Na1/2)TiO3 (BNT)-based solid solution systems, 0.90(Bi1/2Na1/2)TiO3-0.06BaTiO(3)-0.04(Bi1/2Li1/2)TiO3 (BNLBT), aiming to increase the depolarization temperature T-d without deteriorating the piezoelectric properties. A dense BNLBT ceramics doped with CuO 1.0 wt% was fabricated by a conventional ceramic fabrication process with a low-sintering temperature at 940 degrees C, which is 200 degrees C lower than those for non-doped BNLBT ceramics. In addition, the CuO-doped BNLBT ceramic was quenched immediately after the sintering process at 940 degrees C, and the piezoelectric constant and T-d were measured. The T-d values of CuO-doped BNLBT systems with and without quenching were 143 and 78 degrees C, respectively. This showed that T-d Cu-doped ceramics increased by approximately 60 degrees C due to quenching. In addition, the electromechanical coupling factors k(33) of quenched and non-quenched Cu-doped BNLBT ceramics were approximately 0.58, showing no significant deterioration of piezoelectric activity caused by quenching.