采用传统固相法制备了(1-x)BiScO3-xPbTiO3(BSPT)(x=0.58~0.66)铁电陶瓷.经XRD分析发现,BSPT体系三方相和四方相的准同型相界(MPB)在x=0.62附近.在准同型相界附近x=0.62处BSPT陶瓷的压电常数d33和平面机电耦合系数kp具有极大值,但机械品质因素Qm却最小.对BSPT体系及其它钙钛矿型ABO3化合物的结构稳定性进行了讨论,发现容差因子t和离子键百分比p可作为判定钙钛矿结构形成难易程度的基本参数,容差因子t越接近1且离子键百分比p越大的化合物,越容易合成稳定的钙钛矿结构.
The ( 1-x ) BiScO3-xPbTiO3 (BSPT) ( x = 0.58 - 0.66) ferroelectric ceramics were prepared by using traditional solid state process. X-ray diffraction analysis revealed that BSPT had a pemvskite structure, in which the morphotmpic phase boundary (MPB) separating the rhombohedral and tetragonal phase exited near x = 0.62. The BSPT ceramics for x = 0.62 showed the enhancement in planar electromechanical coupling factor kp and piezoelectric constant d33, however the lowest mechanical quality factor Qm. The structural stability of the BSPT system and other pemvskite-type ABO3 compounds was discussed. It was found that the tolerance factor t and the amount of ionic bonding p are two basic parameters to effectively affect the stability of the pemvskite structure, and the ABO3 compounds, which have a tolerance factor t 1 and a high amount of ionic bonding p, should be extremely stable pemvskite structures.