Microstructure and Properties of 0.95K_0.47Na_0.47Li_0.06NbO₃-0.05Ba_xSr_1-xTiO₃ Lead-free Piezoelectric Ceramics

The 0.95K0.47Na0.47Li0.06NbO3-0.05BaxSr1-xTiO3 lead-free piezoelectric ceramics were prepared by traditional ceramic sintering technique,and their microstructure,piezoelectric and dielectric properties were analyzed.The results indicate that the ceramics sintered at 1 165 ℃ for 4 h in air exhibited a single structure.The properties of the ceramic first increase then decrcased with inceasing x and the ceramic with x=0.85 exhibited the following optimum properties: piezoelectric constant d33 =136 pC/N,electromechanical coupling coefficient kp=39%,mechanical quality factor Qm=146,dielectric constant εr=1 327 and dielectric loss tan δ=0.021.