Piezoelectric and dielectric properties of Bi0.5(Na0.84K0.16)0.5TiO3-Ba(Zr0.04Ti0.96)O3 lead free piezoelectric ceramics

Lead free piezoelectric ceramics (1-x)Bi-0.5(Na0.84K0.16)(0.5)TiO3-xBa(Zr0.04Ti0.96)O-3 (BNKT-BZT100x, wherein x ranged from 0 to 10 mol.-%) were fabricated by a conventional mixed oxide route, whose BZT content effect on electrical properties and crystalline structures was investigated. X-ray diffraction investigation showed that BZT effectively diffused into BNKT lattice and formed a solid solution during sintering, and their crystalline structures changed from rhombohedral phase to tetragonal phase as the BZT content was increased. Piezoelectric property measurements revealed that the BNKT-BZT4 ceramics had the highest piezoelectric performance: piezoelectric constant d(33) reached 178 pC N-1 and planar electromechanical coupling factor k(p) was up to 0.33. The influence of Bi2O3 doped content on electrical properties and crystalline structure of the BNKT-BZT4 ceramics were also studied, and found that the piezoelectric property of the ceramics was enhanced when Bi2O3 was doped.