【摘要】 用分析电镜和高分辨电镜观测了BaTiO₃电容器陶瓷的晶粒壳-芯结构与铁电畴。首次发现本实验的BaTiO₃陶瓷的晶粒壳-芯结构由Nb原子的不均匀分布而形成。晶粒芯为贫Nb的铁电相区,而晶粒壳处由富Nb的顺电相组成。并且,壳-芯晶粒含量和壳-芯区域的大小与BaTiO₃陶瓷的性能可能存在一定关系。研究结果表明,壳-芯边界不同于通常晶粒边界结构,而在铁电畴的畴界处,存在一维方向几埃到数十埃的原子紊乱过渡区。更多还原

【Abstract】 The grain core-grain shell structure and ferroelectric domains of BaTiO₃ capacitor ceramics were studied by using analysis electron microscopy and high resolution electron microscopy. The results have firstly revealed that the core-shell structure is formed due to the inhomogeneous distribution of Nb atoms. The grain core is a ferroelectric domain region with a few of Nb atoms and the grain shell is no-ferroelectric domain region with rich Nb atoms. The content of grains with core-shell and the thickness of the grain shell may influence the dielectric properties. The results also show that the disordered region located at the ferroelectric domain boundary is about several to tens angstrom along the {001} lattice and the interface of core-shell is different from the general grain boundary and the domain boundary.更多还原