Composition- and Temperature-Dependent Large Strain in (1-x) (0.8Bi0.5Na0.5TiO3-0.2Bi0.5K0.5TiO3)-xNaNbO3 Ceramics
Composition- and Temperature-Dependent Large Strain in (1-x) (0.8Bi0.5Na0.5TiO3-0.2Bi0.5K0.5TiO3)-xNaNbO3 Ceramics
复制标题
DOI：
10.1111/jace.13407
复制
发表时间：
2015-04-01
影响因子：
3.9
通讯作者：
Li, Mengmeng
中科院分区：
文献类型：
--
作者：
Dong, Guangzhi;Fan, Huiqing;Li, Mengmeng
采用固相反应法制备了（1-x）（0.8Bi（0.5）Na（0.5）TiO（3）-0.2Bi（0.5）K（0.5）TiO（3））- xNaNbO（3）（BNKT-xNN）无铅压电陶瓷。纯BNKT组合物在室温下表现出电场诱导的不可逆结构转变从伪立方铁电菱面体相。随着NN的替代，铁电-弛豫温度TF-R降低到室温以下，出现了由非遍历到遍历的弛豫转变，其特征为夹捏状极化和芽状应变滞回线。BNKT-0.04NN复合材料在55 kV/cm驱动电场下的应变值约为0.445%，归一化应变约为810 pm/V，其大应变归因于电场诱导的弛豫相和铁电相的可逆相变。
Ternary solid solutions of (1-x)(0.8Bi(0.5)Na(0.5)TiO(3)-0.2Bi(0.5)K(0.5)TiO(3))- xNaNbO(3) (BNKT-xNN) lead-free piezoceramics were fabricated using a conventional solid-state reaction method. Pure BNKT composition exhibited an electric-field-induced irreversible structural transition from pseudocubic to ferroelectric rhombohedral phase at room temperature. Accompanied with the ferroelectric-to-relaxor temperature TF-R shifted down below room temperature as the substitution of NN, a compositionally induced nonergodic-to-ergodic relaxor transition was presented, which featured the pinched-shape polarization and sprout-shape strain hysteresis loops. A strain value of similar to 0.445% (under a driving field of 55kV/cm) with large normalized strain of similar to 810pm/V was obtained for the composition of BNKT-0.04NN, and the large strain was attributed to the reversible electric-field-induced transition between ergodic relaxor and ferroelectric phase.