Doping Effects on the Characteristics of PbTiO3-based Ceramics and Their Applications
| Autor: | Te-Yi Chen, 陳德一 |
|---|---|
| Rok vydání: | 2001 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 89 It is essential for piezoelectric materials with large electromechanical coupling factor kt and small planar electromechanical coupling factor kp for the applications of piezoelectric transformers with thickness extension vibration mode. In general, lead zirconate-titanate (PZT) solid solution family ceramics not only have a large coupling factor kt for piezoelectric stiffened mode, but also have a large electromechanical coupling factor k31 and kp for piezoelectric unstiffened effect. However Lead titanate (PbTiO3) family ceramics have large piezoelectric anisotropy, where kt is larger than 50﹪and kp is less than 5﹪, which can be utilized for the piezoelectric transformer applications. In this research, effects of calcium, strontium and cadmium dopants on the piezoelectric and dielectric properties of Sm-modified PbTiO3 ceramics have been investigated. Sm-modified PbTiO3 ceramics were prepared by conventional mixed-oxide methods. We successfully showed that Ca, Sr and Cd additives are helpful to obtain much higher thickness electromechanical coupling coefficient, kt, than that of conventional PbTiO3 based ceramics and still keep small planar electromechanical coupling coefficient, kp. Microstructural and compositional analyses of these doped ceramics have been carried out using XRD and SEM. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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