摘要
采用传统固相烧结法制备性能良好的铁酸铋(BiFeO3,BF)掺杂的铌酸钾钠(K0.5Na0.5NbO3,KNN)压电陶瓷(BF-KNN),着重研究BF摩尔(下同)掺量对KNN结构与压电性能的影响规律以及BF-KNN陶瓷的烧结工艺。结果表明:适量BF有利于提高BF-KNN的压电性能,当BF掺量≥1%后,压电性能急剧降低。与仅烧结一次的样品相比,二次烧结BF-KNN陶瓷形成更加稳定的正交晶系钙钛矿结构,陶瓷组织致密,压电性能大幅度提高,压电常数(d33)、平面机电耦合系数(kp)与机械品质因数(Qm)分别达134pC/N、46%和364,但介电性能明显降低,相对介电常数(εr)从退火前的554降至388。一次、二次烧结样品的体积密度分别为4.12g/cm3和4.36g/cm3,相对密度分别为91.35%和96.67%。在温度低于490℃、频率为100kHz时,二次烧结样品的介电损耗tanδ<5%,其Curie温度高达420℃。
Piezoceramics BiFeO3-K0.5Na0.5NbO3（BF-KNN） with good piezoelectric properties was prepared by a traditional sintering technique.The sintering process and effects of BF mole fraction（the same below） on microstructure and piezoelectric properties of the KNN were investigated.Results show that adding a small quantity of BF can increase the piezoelectric properties of the KNN. However,the piezoelectric properties of the KNN evidently decrease when BF content is over 1%.Compared with the ceramics first sintered,the ceramics sintered secondarily form a stable perovskite structure with orthorhombic system,a dense structure and good electrical properties with the piezoelectric constant（d33） ,electromechanical coupling factor（kp） and mechanical quality factor（Qm） at 134 pC/N,46%and 364 respectively.However,its dielectric property evidently decreases,with the relative dielectric constant（εr） decreasing from 554 to 388.The bulk densities of the ceramics first sintered and then secondarily sintered are 4.12 g/cm^3and 4.36 g/cm ^3 respectively,with relative densities at 91.35%and 96.67%,respectively.The dielectric loss（tanδ） of the ceramic sintered secondarily is lower than 5%at 100 kHz.The ceramic sintered secondarily has also higher Curie temperatures of 420℃.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2010年第3期363-368,共6页
Journal of The Chinese Ceramic Society
基金
广西信息材料重点实验室基金(桂科能0710908-09-Z
0710908-15-Z)
广西创新团队基金
广西教育厅科研(200807LX121)资助项目
关键词
铌酸盐压电陶瓷
压电性能
烧结工艺
二次烧结
niobate piezoceramics
piezoelectric properties
sintering process
sintering secondarily
