High Piezoelectric and Dielectric Properties of La-Doped 0.3Pb(Zn1/3Nb2/3)O3–0.7Pb(ZrxTi1−x)O3 Ceramics Near Morphotropic Phase Boundary
Abstract:La-doped 0.3Pb(Zn1/3Nb2/3)O3–0.7Pb(ZrxTi1−x)O3 (x=0.5–0.53) piezoelectric ceramics with pure perovskite phase were synthesized by a two-step hot-pressing route. The piezoelectric properties of various compositions near the morphotropic phase boundary (MPB) were systematically investigated. Not only was the exact MPB of this system determined via X-ray diffractometry analysis, but also the peak of piezoelectric properties was found near the MPB. The optimum piezoelectric properties of this series were observed in the specimen with Zr/Ti=51/49. The piezoelectric coefficient (d33) and electromechanical coupling factor (kp) were 845 pC/N and 0.70, respectively, which have not been reported in this system so far. Large permittivity (r=4088) and permittivity maximum (m=29 500) were also obtained for the poled specimens. The temperatures (Tmax) of the permittivity maxima ranged from 206° to 213°C with various Zr/Ti ratios.
Document Type: Research Article
Affiliations: State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China
Publication date: August 1, 2005