摘要
用两步合成法制备了（１－ｘ）Ｐｈ（Ｎｉ１／３Ｎｂ２／３）Ｏ３－ｘＰｂＴｉＯ３（ｘ＝０．３０～０．４０）陶瓷，对其相 结构和介电性能进行了研究．ＸＲＤ分析表明，准同型相界在ＰＴ含量ｘ＝０．３４～０．３８范围内． 介电性能研究结果表明；组成在准同型相界处的试样，其介电常数呈现最大值．同时还发现， 准同型相界处的陶瓷出现介电双峰，其中一个为弛豫型铁电相向顺电相转变的相变峰；另一个 介电峰处于１３０～１５０℃的高温区，可能是由镍离子变价、相结构变化等缺陷引起的松弛极化 产生的．
x)PNN-xPT(x=0.30-0.40) ceramics were prepared by a two-steps synthesis method. Phase structure and dielectric properties were studied. Morphotropic phase boundary exists in (1-x)PNN-xPT system at about x=0.34-0.38 composition range according to XRD analysis. Di- electric properties measurments showed that the optimum value of dielectric constant was obtained and the phenomenon of dielectric dual peaks was found for composition near the morphotropic phase boundary. One dielectric peak is phase transition peak from relaxor ferroelectric phase to paraelectric phase. The other peak lying in 130-150℃ temperature range results from relaxational polarization of the valence change of Ni ion and kinds of defects in (1-x)PNN-xPT system.
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
2000年第5期839-843,共5页
Journal of Inorganic Materials
基金
西安交通大学科学研究基金!(1999年度)资助
关键词
铌镍酸铅
准同型相界
介电性
铁电体
驰豫型
lead nickle niobate
morphotropic phase boundary
dielectric properties
dielectric dual peaks
relaxational polarization
