摘要
采用氧化物一次合成法制得了纯钙钛矿相的 Pb(Fe_(1/2)Nb_(1/2))O_3陶瓷。经介电和热激发电流的测量,发现热激发电流峰温度和介电峰温度不一致。用过渡相区模型作了较好的解释。认为它仍为典型的弛豫型铁电体。本文对其介电弛豫不明显,即△T(0.1—100kHz)=0℃的原因以及 Nb^(5+),Fe^(3+)离子在氧八面体中所处的状态作了讨论。
A Pb(Fe_(1/2)Nb_(1/2))O_3 ferroelectric ceramic with single perovskite phase was pre-pared using mixing and calcining the constituent oxides.The temperature dependences ofdielectric constant and thermally stimulated current were measured.The results indicate that thetemperature of maximum thermally stimulated current is lower than that of maximum dielectricconstant,and it was interpreted with the view of transitional phase region.It was concluded thatPFN is a typical ferroelectric relaxor.The reason of weak dielectric dispersion and the status ofNb^(5+),Fe^(3+)in octahedral were discussed.
基金
国家自然科学基金
B587023
关键词
弛豫型
铁电体
介电弥散
陶瓷
ferroelectric relaxor
dielectric dispersion
ferroelectric microdomain
order
disorder
