Bi3.55Nd0.45Ti3-xNbrO12(x=0, 0. 02, 0. 04, 0. 08, 0. 15) ferroelectric ceramics of a layered perovs-kite structure with no lead were prepared using the solid-state reaction. Bi3.55 Nd0. 45 Ti3-x NbxO12 ceramics were pure phases and no other phases appeared by X-ray diffraction( XRD); and it showed the peak(117) had a lower angle shift with niobium concentration increasing. Scanning electron microscope(SEM) showed the platelike shapes of the samples, which were related to the layered perovskite structure of bismuth titanate. Dielectric properties were measured with an impedance analyzer LCR(HP 4284A). The Curie temperature of A- and B-site-modified Bi4Ti3O12 ceramic was 275℃. Compared with the Curie temperature of Bi4Ti3O12 (675℃), it was 400℃ lower. In the process of studying the ferroelectric properties through Radiant Ferroelectric test system, in contrast to x=0. 05, when x=0. 15, the coercive field and remnant polarization decreased 5kV/cm and 2μC/cm2, respectively.%采用固相烧结法制备了Bi3.55 Nd0.45 Ti3-xNbx O12 (x=0、0.02、0.05、0.08、0.15)系层状钙钛矿结构无铅铁电陶瓷.通过X射线衍射仪(XRD)可以看出陶瓷样品为铋层状钙钛矿结构,并无杂相生成.随着Nb的含量增多,其衍射峰向低角度移动.从扫描电子显微镜( SEM)可以看出陶瓷晶粒为片状.利用阻抗分析仪LCR(HP4284A)测试了陶瓷的介电性能,研究表明AB位共掺钛酸铋陶瓷的居里温度在275℃左右,而Bi4 Ti3 O12的居里点是675℃,前者比后者下降了400℃.在利用铁电综合测试系统对铁电性能的研究过程中发现,与x=0.05相比,x=0.15的矫顽场(Ec)和剩余极化强度(2Pr)分别减小了5kV/cm和2μC/cm2.
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