Dielectric and piezoelecrtic properties of lead-free (Na0.5Bi0.5)TiO3–NaNbO3 ceramics

In this paper, lead-free [Na0.5(1+x)Bi0.5(1−x)](Ti(1−x)Nbx)O3 (x = 0–0.08) ceramics were fabricated by using conventional ceramic technique. The phase structure of the solid solution has been determined by the X-ray diffraction. Dielectric study revealed that the dielectric relaxor behavior becomes more obviously by doping of NaNbO3 into (Na0.5Bi0.5)TiO3. The samples in the composition range from x = 0.01 to 0.02 exhibited excellent electrical properties, piezoelectric constant d33 = 80–88 pC/N; electromechanical planar coupling coefficients kp = 17.92%. The results show that the [Na0.5(1+x)Bi0.5(1−x)](Ti(1−x)Nbx)O3 ceramics are one of the promising lead-free materials for ultrasonic transducer applications.