A位掺杂对BF-PZT压电陶瓷性能的影响

采用XRD分析了固相法制备0.10BF-0.90PZT压电陶瓷不同锆钛比的相结构,并研究了A位掺杂量对体系介电、压电性能的影响。研究表明:体系的相结构均为单一的钙钛矿结构;随着锆钛比的降低,体系的相结构由三方相向四方相转变,且体系的准同型相界位于锆钛比为1.24附近;在锆钛比为1.24组分中A位掺杂量为0.16时,介电和压电性能达到最佳值,即:相对介电常数(ε33T/ε0)为4118、机电耦合系数(kp)为0.85、压电常数(d33)为803 pC/N、介电损耗(tanδ)为2.21%、机械品质因子(Qm)为49.8;居里温度(Tc)为214℃且掺杂浓度达到饱和;并发现该体系具有典型的介电弛豫特性。

The Effect of A Doping on the Electric Properties of BF-PZT Piezoelectric Ceramics

The phase structure of 0.10 BF-0.90 PZT piezoelectric ceramics by traditional solid-state process with different Zr/Ti ratio were analyzed by XRD. And the influence of A-site doping on the dielectric and piezoelectric properties of 0.10 BF-0.90 PZT ceramics were studied. The results showed that the phase structure of ceramics are single perovskite, and the phase structure of system changes from trigonal phase to tetragonal phase with the Zr/Ti ratio decreasing. the morphotropic phase boundary(MPB) of system lies near 1.24 of Zr/Ti ratio,and the dielectric and piezoelectric properties reach the best value when the doping amount of A-site is 0.16 mol in the Zr/Ti ratio of 1.24. Namely the dielectric constant( ε33T/ε0) is 4118, the electromechanical coupling factor(kp) is 0.85,the piezoelectric constant(d33) is 803 pC/N, the loss tangent(tanδ) is 2.21%, the mechanical quality factor(Qm) is 49.8, the Curie temperature is 214 ℃,and the doping concentration reaches saturation. It is found that the dielectric relaxation characteristic of the system is typical.