Relationship between structure and properties in high-temperature Bi(Al0.5Fe0.5)O3–PbTiO3 piezoelectric ceramics

Ceramic samples of xBi(Al0.5Fe0.5)O3–(1 − x)PbTiO3 (BAF-PT, x = 0.05–0.5) solid solutions were fabricated using the conventional solid state reaction method. X-ray diffraction analysis revealed that all compositions can form single perovskite phase with tetragonal symmetry. The relationship between the tetragonal lattice parameters, tetragonality c/a, cell volume, and ferro-piezoelectric characterization as a function of x was systematically investigated. The BAF modification can effectively improve the poling condition at a proper BAF content. A combination of piezoelectric constant of d33 (50–60 pC/N), electromechanical planar coupling coefficients of kp (20.3–22.5%), and high Curie temperature Tc (>478 °C) suggested that BAF–PT could be a good candidate for high-temperature piezoelectric applications.

► Low-cost Bi-based high temperature piezoceramics.
► A new high temperature system with Curie point >478 °C, compared to BiScO3–PbTiO3 (450 °C).
► Effectively improve the poling conditions.