The quenching effects for depolarization temperature of (Bi _0.5 Na _0.5 )TiO ₃ ceramics with Mn dopants

Abstract

Abstract Lead-free ferroelectric and piezoelectric ceramics, (Bi 0.5 Na 0.5 )TiO 3 (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 + x Mn (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 (Δ T 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.