Influence of the size of A-site ion on structure and properties of AxSr1-xBi2Ta2O9 (A = Ca, Ba) ferroelectric crystalline

• Main Authors: HSIN-CHIEN SHIH, 施信健
• Other Authors: Y. L. Jiang
• Format: Others
• Language: zh-TW
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/d6756g

碩士 === 國立中興大學 === 電機工程學系 === 90 === Abstract The AxSr1-xBi2Ta2O9 (A = Ba, Ca; X = 0.2,0.4~1.0) were synthesized by solid-state reaction sintering method. The structures and lattice constant of those crystallizations were refined by X-ray powder diffraction. Effect of ionic radius for crystallizations shows great influences on dielectric, ferroelectric and piezoelectric properties. The BaxSr1-xBi2Ta2O9 with x > 0.2 show the large dielectric constant (er’) at room temperature and low Curie temperature (Tc). The CaxSr1-xBi2Ta2O9 with x > 0.4 show that the Curie temperature over 580. The hysteresis loop could be found in CaxSr1-xBi2Ta2O9 with x = 0.0, 0.2 ~ 1.0 at room temperature. For BaxSr1-xBi2Ta2O9 with x = 0.0, 0.2 and 0.4 the hysteresis loop could be observed at room temperature. But it is not apparent with x > 0.4. Piezoelectric properties and piezoelectric parameter (kt, kp) were also found.