On the basis of eutectic behavior of PbTiO3-PbZrO3-Bi(Zn0.5Ti0.5)O-3 ternary system, perovskite-structured Pb0.98Bi0.02Zr0.51Ti0.48Zn0.01O3 ceramics were able to be prepared using conventional electronic ceramic processing at low sintering temperature compatible with Ag as inner electrode materials, promising for co-firing technology to fabricate monolithic multilayer piezoelectric transducers. The dependence of its piezoelectric properties on sintering temperature and various dopants were investigated experimentally and a piezoelectric property with dielectric constant of epsilon(T)(33)/epsilon(0) = 1190, dielectric loss of tan delta = 0.6%, piezoelectric coefficient of d(33) = 270 pC/N, planar coupling coefficient of k(p) = 0.54, thickness coupling coefficient of k(t) = 0.46 and Curie temperature of T-c = 346 degrees C was obtained for the 0.5% Co-doped Pb0.98Bi0.02Zr0.51Ti0.48Zn0.01O3 ceramics sintered at 950 degrees C. (c) 2011 The Japan Society of Applied Physics

Perovskite-structured Pb0.6Bi0.4(Ti0.75Zn0.15Fe0.1)O-3 ceramic patches were prepared with conventional electronic ceramic processing on the basis of its near-zero thermal expansion coefficient, in contrast to most of PbTiO3-based solid solutions with decreasing tetragonality and Curie temperature. For the 1% Nb+0.5% Mg-doped samples sintered at 1050 degrees C, enhanced tetragonality of c/a=1.100 and Curie temperature of T-c=705 degrees C, dielectric constant of epsilon=204, dielectric loss of tan delta=1.7%, and piezoelectric constant of d(33)=2.0 pC/N were obtained.

Two kinds of robust modified lead titanate piezoelectric ceramics were prepared with conventional solid state reaction methods, corresponding to two techniques of decreasing tetragonality and thermal expansion coefficient to reduce those crack stresses resulting from ferroelectric phase transition. Their structure, dielectric, ferroelectric and piezoelectric properties were experimentally studied in comparison for the Pb0.88Sm0.08 Ti0.98Mn0.02O3 and Pb0.6Bi 0.4(Ti0.75Zn0.15Fe 0.10)O 3 systems. © Taylor & Francis Group, LLC.

介绍了V形超声电机的结构和驱动原理。利用有限元理论建立了具有复杂形状的V形超声电机定子的动力学模型,并对定子的动力学特性进行了求解。利用参数化语言APDL编程对电机定子进行相应的优化计算,优化了定子压电陶瓷的安装配置形式,提高了驱动端面质点的振幅。研究表明,优化后的定子结构满足了预期的设计要求,并且提高了计算精度和设计效率。

摩擦界面对超声电机的性能有至关重要的影响。文章针对一种基于面内振动的直线驻波超声电机,结合电机的工作振型,对电机的定、转子的接触过程进行了详尽的论述,建立了堵转情况下的最大输出力模型;并进行了仿真研究。通过仿真可以得出超声电机的堵转推力受定、转装配间隙的影响最大。在电机已完成制造的情况下。如要得到较大的堵转推力,可适当调整定转子的装配间隙。

A V-shaped linear ultrasonic motor with a stator and a slider has been developed. The stator consists of two orthogonal Langevin actuators which is joined together in their ends. The Langevin actuators are symmetrical and have same first order longitudinal mode. A linear motion of the slider is generated by friction between the stator and the slider when the two first order longitudinal modes are combined. In this paper, structural dynamic design on the stator is completed with Finite Element Method(I-EM). The prototype motor is manufactured based on the design results. The operation modes of the stator and the output performances of the motor are tested. The diameter and length of the Langevin actuator are 20mm and 58mm, respectively. The mass of the stator is 290g. The first order longitudinal frequency of the Langevin actuator is 27.47 kHz (FEM simulating result) and 27.36 kHz (expermental result), respectively. The maximum driving force of the motor approaches 40N. The maximum velocity of the motor is about 100 mm/s. So the stator's operation modes are consistent with the design results, and the motor output properties have characteristics of slower velocity and stronger force.

In general, commercial PZT piezoceramics are sintered at temperature above 1200°C. Here, one low-temperature sintering technology was developed for PZT piezoceram-ics by adding perovskite-type ferroelectrics with low sintering temperature, alternative to adding non-piezoelectric low-melting glass or eutectic oxides. Through solid state reaction mechanism, very densified piezoceramics of (Pb0.95Sr0.05)(Zr0.53 Ti 0.47)O3 with 0.6PbTiO3-0.3Bi(Zn0.5Ti 0.5)O3-0.1BiFeO3 as sintering additive were obtained below 1050°C. The phase of (Pb,Bi,Sr)(Zr,Ti,Zn,Fe)O3 solid solution piezoceramics was demonstrated to be single-phased perovskite structure and the measurements of dielectric, ferroelectric and piezoelectric properties showed good piezoelectric performance equivalent to PZT-8.