Electrical properties and low temperature sintering of BiAlO_3 doped (Ba_(0.85)Ca_(0.15))(Zr_(0.1)Ti_(0.9))O_3 lead-free piezoelectric ceramics

摘要

(1 - x)(Ba_(0.85)Ca_(0.15))(Zr_(0.1)Ti_(0.9))O_3-xBiAlO_3((1-x)BCZT-xBAO) piezoelectric ceramics were synthesized by a solid-state reaction method. Effects of BAO content on the sintering temperature, phase structure, microstructure and electrical properties of BCZT ceramics were investigated. X-ray diffraction revealed a phase transition from orthorhombic to tetragonal phases at x = 0.3-1.0 mol%. The grain size gradually becomes smaller with increasing the BAO content. It was observed that the introduction of BAO content not only decreased the sintering temperature from 1450 to 1300 ℃ but also enhanced the electrical properties and temperature stability. The favorable electrical properties (d_(33) = 568 pC/N, k_p = 0.54, P_r = 8.17 μC/cm~2, E_c = 3.45kV/cm, ε_m = 13,298, ε_r = 3375, tanδ = 0.021, T_c = 72 ℃ and S = 0.06 %) were demonstrated for the BCZT based ceramics sintered at 1300 ℃ with x = 0.8 mol%. These results indicated that the ceramics sintered at low temperatures was promising for piezoelectric applications.