Lead-Free Relaxor-Like 0.75Bi0.5K0.5TiO3-0.25BiFeO3 Ceramics with Large Electric Field-Induced Strain

Dense and phase-pure ferroelectric ceramics of 75 mol.% Bi0.5K0.5TiO3 - 25 mol.% BiFeO3 are prepared by the conventional solid state reaction method. Their crystal structure is analyzed and discussed. The dielectric and piezoelectric properties of the ceramics are investigated at various temperatures. The ceramics exhibit relaxor-like dielectric properties and high electric field-induced strain (equivalent to 250-300 pm/V at 25-75 degrees C), not previously reported for this composition, making it a promising lead-free alternative for actuator applications.