退火对Ba4Sm2Fe2Nb8O30铁电体结构和性能的影响  

Effect of annealing on structure and properties of Ba4Sm2Fe2Nb8O30 ferroelectric

作　　者：罗国仕[1] 郑兴华[1] 骆统领 刘洋[1] 肖腾[1] Luo Guoshi, Zheng Xinghua, Luo Tongling, Liu Yang, Xiao Teng(College of Materials Science and Engineering, Fuzhou University, Fuzhou Fujian 350108, Chin)

机构地区：[1]福州大学材料科学与工程学院

出　　处：《金属热处理》2018年第3期151-154,共4页Heat Treatment of Metals

基　　金：国家自然科学基金(51001027);福建省发改委项目(NDRC2013);福州大学福州基金(2010-XQ-01)

摘　　要：采用高温烧结制备钨青铜型Ba_4Sm_2Fe_2Nb_8O_（30）铁电体,研究了氧气下退火热处理对其晶体结构、介电性能和铁电性能的影响。研究表明,退火处理后,Ba_4Sm_2Fe_2Nb_8O_（30）铁电体仍为钨青铜单相,但是晶胞体积略有增大;介电常数明显降低,而介电损耗略有升高。退火前后Ba_4Sm_2Fe_2Nb_8O_（30）铁电体均观测到典型的电滞回线：退火前其矫顽电场E_c=8.35 k V/cm,剩余极化强度P_r=0.62 C/cm^2;而退火后铁电性能改善为E_c=7.2 k V/cm,P_r=1.57 C/cm^2。The Ba_4Sm_2Fe_2Nb_8O_（30）ferroelectrics with tungsten bronze structure were prepared by high temperature sintering.And effect of annealing in O_2on the structure,dielectric and ferroelectric properties was investigated.The results show that the tungsten bronze phase is detected in the as-sintered and annealed Ba_4Sm_2Fe_2Nb_8O_（30）ferroelectric.After annealing in O_2atmosphere,the unit cell of the Ba_4Sm_2Fe_2Nb_8O_（30）ferroelectric expands slightly.And the dielectric constant obviously reduces and the dielectric loss slightly increases.Typical electric hysteresis loops can be observed for both as-sintered and annealed Ba_4Sm_2Fe_2Nb_8O_（30）ferroelectric.The coercive electric field E_c,and residual polarization P_r,are 8.35 k V/cm and 0.62 C/cm^2,respectively for as-sintered Ba_4Sm_2Fe_2Nb_8O_（30）ferroelectric,but both parameters improve to 7.2 k V/cm and 1.57 C/cm^2,respectively for as-annealed Ba_4Sm_2Fe_2Nb_8O_（30）,which is with stronger ferroelectricity.

关 键 词：钨青铜结构 退火 氧空位 介电性能 铁电性能 

分 类 号：TQ28[化学工程—有机化工]