本文从材料科学的角度出发，利用传统固相反应法制备了系列立方Bi基焦绿石材料，对在不同气氛下的退火处理材料进行结构、性能表征。讨论了材料组成、退火工艺对固体微结构和介电弛豫机制的作用规律。主要研究成果如下： （1）对比BZNM系列材料的的结构信息和介电温度特性，发现B位四价离子半径的增加使得氧偏移量变大，发生畸变的顶角相连的BO6八面体骨架结构对填充在其间的A、O‘离子造成了一定程度的挤压，使得A、O‘离子之间的作用力增强，弛豫度也随之增加；B位的易变价四价离子在高温或是还原气氛下易被还原为低价离子，由于局域的电价不平衡易产生弱束缚电荷，在较高温度下和电场作用下形成漏导电流，造成介电损耗增加。产生高温漏导现象的温度向低温方向移动。 （2）研究了(Bi1.5Zn0.5-xSrx)(Ti1.5Nb0.5)O7（BZSTN，x=0～0.5）系列陶瓷的结构和介电弛豫特性。结合对弛豫能等参数的计算发现低温区的弛豫现象源于偶极子转向极化效应；而高温区的弛豫现象则源于形成偶极子、缺陷偶极子的荷电载流子、正、负离子空格点在外界热扰动下克服之间的Coulomb力重新形成游离在结构中的离子、缺陷、带点空格等荷电粒子的振动、转动所产生的共振效应。 （3）研究了(Bi1.5Zn0.5-xLix)(Ti1.5Nb0.5)O7-xFx（BZTN-LiF，x=0、0.1、0.2、0.3、0.4、0.5）系列陶瓷的结构和介电弛豫特性。随着LiF掺杂量的增大，晶胞的体积也逐渐增大，LiF的添加利于陶瓷材料的烧结。弛豫温度随着LiF掺杂量的增大向高温方向移动，说明氧空位、缺陷数目的增加使得材料中缺陷偶极子的数目增加，而在液氮的测试温度下，偶极子的极化反转频率在我们所测试的频率范围内，因此有弛豫现象产生；弛豫温度向高温方向移动则说明偶极子之间的作用力增强，偶极子随外电场反转需要的能量随之增加； （4）通过对Debye、V-F关系、新玻璃等弛豫模型及C-W、Barrett Equation等介电模型对材料的弛豫能、弛豫度等弛豫参数进行计算，结合材料的组成、结构可以有效地分析材料的弛豫特性同结构的关系。 （5）对比不同热处理气氛下材料的结构和介电性能，发现：热退火工艺可以有效减少玻璃相、晶界等对介电性能的恶化；对大半径离子取代、高浓度离子掺杂材料的介电性能、弛豫特性对热处理气氛尤其敏感：结构上无序程度较大的材料在还原气氛下使得结构中弱束缚的O’离子失去O变成氧空位，结构上的松弛化导致性能上出现弛豫现象。

Taken Materials Science as the viewpoint and the relationship of structures and properties the springboards, groups of Bi-based pyrochlore materials were prepared by conventional solid-state reaction methods. Annealing processing was applied to verify the micro-defects information of series ceramics. The defects information and dielectric relaxation properties had been studied. The detailed microstructure information related to the dielectric relaxation of materials had been summarized. The influence of chemical composition on the microstructure and dielectric properties of pyrochlores materials had been investigated. We have got some conclusion as following: The effect of B site substitution on dielectric properties of BZMN ceramics was investigated. It is discovered that a shift of the relaxation peak for the dielectric properties is obviously observed. The difference in the temperature peaks of dielectric relaxation and the parameters of dielectric relaxation was analyzed: The increasing of B site ion radius causes strong correlation among highly polarizable octahedrals. The valence of B site ion may change easily in reducing atmosphere, which raises the conductivities of the material. The dielectric relaxation properties of (Bi1.5Zn0.5-xSrx)(Ti1.5Nb0.5)O7 (BZSTN, x=0~0.5) ceramics had been studied, It is discovered that a shift of the relaxation peak for the ε is obviously observed, When x increases samples, A shift of the relaxation peak to high temperature was indicate These provide a experimental basis for further exploration of dielectric relaxation,mechanism:A defect dipole model can explain the phenomenon relaxation in low temperature; ionic polarization model can explain the phenomenon relaxation in high temperature. The dielectric relaxation properties of (Bi1.5Zn0.5-xLix)(Ti1.5Nb0.5)O7-xFx（BZTN-LiF, x=0~0.5) ceramics had been studied. When x increases a shift of the relaxation peak for the dielectric loss is obviously observed, a shift of the relaxation peak to high temperature was caused by activation energy increasing or the interaction energy increasing. Debye model, V-F relationship, New glass model Curie-Wiss’s law and Barrett Equation were used to analysis the property of dielectric relaxation, which can explain the relationship between microstructure and dielectric properties of pyrochlores materials. Thermal annealing is a good way to improve the dielectric properties of Cubic Bi-based pyrochlores, and this effect can be attributed to the decrease of grain boundary. The experimental results revealed after annealing in oxygen ambient, the oxygen vacancies were largly reduced, the stress between boundaries is largly decrease, therefore a decrease of relaxation and an improvement of dielectric properties ware observed in the oxygen annealing samples