Pb(Zr,Sn,Ti)O_3反铁电陶瓷场诱相变性能的改进

ELECTRIC FIELD INDUCED ANTIFERROELECTRIC TO FERROELECTRIC PHASE TRANSITION OF Pb(Zr,Sn,Ti)O_3 CERAMICS AND TAILORING OF PROPERTIES THROUGH COMPOSITION MODIFICATION

为了获得场诱反铁电 (AFEt)—铁电 (FER)相变临界电场Ef 小、电滞ΔE小、场致应变x适当的反铁电陶瓷 ,对Pb(Zr ,Sn ,Ti)O3 采用Ba2 + 置换Pb2 + ,同时在四方反铁电相AFEt—三方铁电FER 相界附近调节Ti/Sn比 ,来控制FER AFEt,AFEt 顺电相 (FEC)之间的相变温度TFA,TC,最终实现了对场诱相变参量 (Ef,ΔE)和反铁电工作温区 (ΔT =TC-TFA)的优化与调节 .获得了ΔE =0 85kV/mm ,Ef=1 6kV/mm ,x =0 1% - 0 2 %可用作开关致动器的新型反铁电陶瓷 .借助于X射线衍射、介电温谱、去极化电流谱、电滞回线等手段得到了这一系统AFEt/FER相界附近的温度 Ti含量相图 .

In order to obtain a new kind of antiferroelectric (AFE\-t) ceramics with lower AFE\-t\|Ferroelectric (FE\-R) switching field E\-f and less hysterisis loss ΔE for application of large displacement actuator, Ba\+\{2+\} ionics was employed to control the relative stability between AFE\-t, FE\-R, and parroelelctrics (PE\-c) phases in (Pb 0 97-x Ba x La 0 02 )(Zr 0 55 Sn 0 35 Ti 0 1 )O 3 (0≤x≤0 2) system. Structural changes and electric properties as a function of Barium content \%x\% have been investigated by X\|Ray diffraction, dielectric properties, polarization and longitudinal strain measurement. It is observed that AFE\-t changes to FE\-R, and finally to ferroelectric relaxors(RFE) as Ba content x increases from zero to 0 2. Based upon these expermental result, we are able to tailor the AFE\|FE switching parameters such as E f, ΔE and AFE\-t operating temperature range ΔT through modifying the Ti/Sn ratio near AFE\-t/FE\-R phase boundary in the (Pb 0 87 Ba 0 1 La 0 02 )(Zr 0 6 Ti y Sn 0 4-y )O 3 (0 04≤y≤0 09) system. Finally, a new kind of AFE\-t ceramics with E f=1 6?kV/mm,ΔE=0 85?kK/mm, and longitudinal strain x=0 1%—0 2% which is appropriate for application of digital actuators has been obtained. Phase diagram with composition located near AFE\-t/FE\-R boundary of the studied system has been determined.