BF-BT基陶瓷实现巨非对称电应变和大压电常数研究  

Research on achieving giant asymmetric electrostrain and large piezoelectric constants on BF-BT based ceramics

作　　者：张浩 周昌荣[1] ZHANG Hao;ZHOU Changrong(School of Materials Science and Engineering,Guilin University of Electronic Technology,Guilin 541004,China)

机构地区：[1]桂林电子科技大学材料科学与工程学院,广西桂林541004

出　　处：《桂林电子科技大学学报》2024年第5期489-497,共9页Journal of Guilin University of Electronic Technology

基　　金：国家科学自然基金(52262017)。

摘　　要：压电制动器广泛应用于精密定位、自适应光学和自动机器人等设备,然而,无铅压电陶瓷中低电应变和低压电应变系数(d_(33)^(*))限制了其实际应用。为了在BF-BT(BiFeO_(3)-BaTiO_(3))基陶瓷中获得高电应变且同时降低驱动场,采用传统固相法制备了SnO_(2)掺杂的BF-BT陶瓷样品,并研究了0.7BF-0.3BT-xSnO_(2)陶瓷的相结构、微观结构、铁电性能和极化老化后的非对称电致应变行为。实验结果表明,适量的掺杂成功构建了多相共存。样品在老化处理后,定向的强极性缺陷偶极子形成了内偏场,当其与外加电场方向相同时会促进自发极化的延展,相反时会阻碍自发极化的翻转,从而导致高度不对称的大电应变,同时降低驱动场以获得大的逆压电系数。研究结果表明,在0.7BF-0.3BT-0.2%SnO_(2)陶瓷中实现了0.7%的高应变和大信号压电系数d_(33)^(*)=1190 pm·V^(-1)。Piezoactuators are widely used in devices such as precision positioning,adaptive optics and automated robots,however,low electrostrain and low piezoelectric strain coefficient(d_(33)^(*))limit its practical application.In order to obtain high electrostrain and reduce the driving field in BF-BT(BiFeO_(3)-BaTiO_(3))based ceramics,a series of trace SnO_(2) doped BF-BT samples were prepared by traditional solid-phase sintering method.The phase structure,microstructure,ferroelectric properties and asymmetric electrostrain behavior of 0.7BF-0.3BT-xSnO_(2) ceramics after poling an aging were discussed.The research results show that multi-phase coexistence is successfully constructed with the appropriate amount of doping.The strongly polarized directional defect dipoles during aged process will form an internal bias field that tends to promote the effects of external fields when they follow the applied field,thereby resulting in the highly asymmetrical strain behavior along with decreased driving field to obtain a large d_(33)^(*).The results show that 0.7% electrostrain and large d_(33)^(*)=1190 pm·V^(-1) are achieved in 0.7BF-0.3BT-0.2%SnO_(2) ceramics.

关 键 词：BF-BT 电致应变 多相共存 缺陷偶极子 内偏场 

分 类 号：TK91[动力工程及工程热物理] O469[理学—凝聚态物理]