Temperature Stability of V_2O_5-Doped KNN-LS-BF Lead-Free Piezoelectric Ceramics

摘要

V_2O_5-doped Na_(0.5)K_(0.5)NbO_3-LiSbO_3-BiFeO_3 (KNN-LS-BF) lead-free piezoelectric ceramics were prepared by the traditional sintering method, and their temperature stability was studied. Characterization of the temperature dependences of dielectric and piezoelectric properties of the V_2O_5-doped KNN-LS-BF ceramics showed that V_2O_5 doping could significantly improve the temperature stability in the temperature range of 30℃ to 420℃ and cause a downward shift in the orthorhombic-tetragonal phase transition to below room temperature. It was also found that the V_2O_5-doped KNN-LS-BF ceramics possess good dielectric and piezoelectric properties (ε_r > 1066, tan δ < 4%, d_(33) > 185 pC/N, k_p > 0.25) in the temperature range of 30℃ to 300℃.