Structural, dielectric, and piezoelectric properties of mn-doped BaTiO 3-Bi(Mg1/2Ti1/2)O3-BiFeO 3 ceramics

Abstract

Mn-doped (0.9 - x)BaTiO3-0.1Bi(Mg1/2Ti 1/2)O3-xBiFeO3 (x = 0.6, 0.7, and 0.8) ceramics were studied as candidate lead-free piezoelectric materials. The crystal structures were a pseudo-cubic perovskite at x = 0.6, a rhombohedral perovskite at x = 0.8, and a mixture of the pseudocubic and rhombohedral perovskite at x = 0.7. The Curie temperature was found to be 470 °C at x = 0.6 and more than 600 °C at x = 0.7 and 0.8. A strong pinning of domain walls was observed for high-field responses at x = 0.7 and 0.8, which was relaxed by high-temperature annealing and subsequent quenching. Piezoelectric properties increased with decreasing x, and the small-field piezoelectric constants d33 and d31 were 94 and 31 pC/N at x = 0:6, respectively. © 2011 The Japan Society of Applied Physics.