Ferroelectric and piezoelectric properties of 0.82(Bi0.5Na0.5) TiO3-(0.18-x)BaTiO3-x(Bi0.5Na0.5)(Mn1/3Nb2/3)O3 lead-free ceramics

Abstract It is an urgency to find capable lead-free piezoelectric ceramics to show effort towards environmental protection. Bi 0.5 Na 0.5 TiO 3 (BNT)-based piezoelectric ceramics is one of the most promising lead-free systems, for which compositional modification is an efficient way to enhance the piezoelectric performance. In this work, lead-free 0.82(Bi 0.5 Na 0.5 )TiO 3 -(0.18- x )BaTiO 3 - x (Bi 0.5 Na 0.5 )(Mn 1/3 Nb 2/3 )O 3 ceramics were synthesized by a conventional solid state reaction method. Polarization and strain hysteresis loops implies a phase transition from FE (ferroelectric phase) to ER (ergodic relaxor). An electric field induced high strain of 0.28% occurred at x  = 0.0275, which was attributed to the coexistence of FE and ER phases. It is considered that our work can help to understand the complex phenomenon observed in BNT-based lead-free system.