钨青铜结构化合物(1–x)Ba_(2)NaNb_(5)O_(15)–xSr_(2)KNb_(5)O_(15)准同型相界的组成及其铁电性能

Ferroelectric Properties of(1–x)Ba_(2Na) Nb_5O_(15)–xSr_2KNb_5O_(15) Tungsten Bronze Structural Compounds with Morphotropic Phase Boundary

与传统铁电材料相比,具有准同型相界(MPB)的铁电体具有增强的介电、压电和电光性能。通过传统固相烧结技术获得致密的(1–x)Ba_(2)Na Nb_(5)O_(15)–x Sr_(2)KNb_(5)O_(15 )(BNN–SKN)钨青铜结构陶瓷二元固溶体系,系统研究了BNN–SKN的结构、介电和铁电性能,探究迄今尚未确定的MPB区域。Ccm2与P4bm共存的MPB在x=0.7附近,随着SKN含量的增加,所测样品的相变温度及介电常数均在x=0.7附近取得极值,T_(m)=170.1℃,ε_(T R)=1 211,ε_(m)=3 326,给出了BNN–SKN体系的铁电性能,并讨论了该二元体系铁电性变化的影响因素。

Ferroelectric materials with a morphotropic phase boundary (MPB) can exhibit enhanced dielectric,piezoelectric,and electrooptic properties,compared with conventional ferroelectric materials.In this paper,dense (1–x)Ba_(2Na) Nb_5O_(15)–x Sr_2KNb_5O_(15)(BNN-SKN) tungsten bronze structured ceramics of binary solid solution system were obtained by a solid-state sintering method.The microstructure and electric properties of BNN-SKN were investigated to explore the potential MPB regions.The MPB coexisting with Ccm2 and P4bm appears as x=0.7.As the SKN content increases,the phase transition temperature and dielectric constant of the measured samples reach their extreme values as x=0.7,i.e.,T_m=170,ε_(TR)=1 211,and ε_m=3 326.In addition,the ferroelectric properties of BNN-SKN system were also analyzed,and the factors affecting the ferroelectric change in this binary system were discussed.