The quenching effects for depolarization temperature of (Bi0.5Na0.5)TiO3 ceramics with Mn dopants

Lead-free ferroelectric and piezoelectric ceramics, (Bi0.5Na0.5)TiO3 (BNT), with Mn dopants were prepared by a quenching procedure after sintering to examine the depolarization temperature T d, and then their electrical properties were investigated. The T d of quenched BNT + xMn (Mn x) decreased with Mn doping. Also, the T d of quenched Mn x was ~60 °C higher than that of ordinary firing (OF) samples. Furthermore, the difference of T d (ΔT d) between the OF and the quenched process increased with increasing of the Mn-substituted amount. The electromechanical coupling factors k 33 of Mn x exhibited the same value after quenching. The coercive electric field E c was increased from 62 to 95 kV cm−1 with increasing of Mn-substituted amount. Thus, the quenching procedure is an effective way of elevating the T d of Mn-doped BNT-based solid solution systems.