The dielectric, piezoelectric and ferroelectric properties of LaAlO3-doped Bi0.5Na0.5TiO3-BaTiO3 lead-free piezoceramics

摘要

LaAlO3-doped Bi0.5Na0.5TiO3-BaTiO3(BNT-BT) lead-free piezoelectric ceramics with compositions near the rhombohedral-tetragonal morphotropic phase boundary (MPB) were prepared and investigated. The introduction of LaAlO3, which makes the ceramics samples avoid being fused, has a relatively large influence on the dielectric, piezoelectric and ferroelectric properties of BNT-BT ceramics. With the increase of doping concentration, these properties get weaker. But when the doping concentration of LaAlO3 is 0.2mol%, the remnant polarization (P-r) and coercive field (E-c) are better than those in pure 0.93BNT-0.07BT ceramics. The ferroelectric properties of this ceramics appear an eccentric enhancement and the domain switch becomes more easily.