Synthesis and piezoelectric properties of lead-free (Bi0.5Na0.5)1−x(BaaSrb)xTiO3 ceramics

A new group of lead-free piezoelectric ceramics, (Bi0.5Na0.5)1−x(BaaSrb)xTiO3 (abbreviated as BNBST[100x−100a/100b], 0<x<1, a+b=1), was synthesized. The ceramics were prepared by conventional ceramic sintering technique, and the ceramics with density of 95% of the theoretical one can be sintered without the atmosphere control during the sintering process. The results of the X-ray diffraction (XRD) data show that the ceramics possess a single perovskite phase. The measurements of dielectric and piezoelectric properties reveal that the ceramics provide relatively high piezoelectric charge constant d33 and high planar electromechanical coupling factor kp. For the BNBST6-95/5 ceramics, d33 is equal to 170pC/N, and kp is equal to 32.0%. The fabrication technique for these ceramics is conventional and stable.