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The constant electric field effect on the radio absorption of crystals BaTiO_(3) and piezoceramics PCR-1

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Journal of Advanced Dielectrics 2020年第1期10卷 144-151页

作者： Eugeny Sidorenko Chan Thi Beat Ngoc Gennady Prikhodko Ivan Natkhin Alexander Shloma Diana Kharchenko Southern Federal University Stachki Avenue 194 Rostov-on-Don 344090Russia University of Transport and Communications Hanoi Vietnam

The effect of a constant electric field(E)on the absorption of microwave electromagnetic energy(L)by BaTiO_(3) crystals and the highly sensitive PCR-1 piezoceramic was *** field dependence of the absorption value LeET at the maximum of the spectrum Lef T has the form of a“butterfly”,and the dependence of the frequency shift of the maximum on the field strength f eET has a hysteretic *** PCR-1 Lef T absorption spectrum at high E is modulated by pulses in a wide frequency *** is assumed that the cause of the amplitude-frequency modulation of the spectrum may be the electromagnetic radiation of incomplete local discharges at the surface of *** change in the magnitude and position of the resonance maximum in the absorption spectra and the appearance of amplitude-frequency modulation Lef T when exposed to a constant field is interpreted from the point of view of changes in the parameters and concentration of the domains walls,as well as the a-and c-domain wedges of mechanical twins resonating in the electromagnetic field.

关键词： Microwave absorption spectrum piezoceramics dispersion domain walls micro breakdowns

Processing and Properties of Porous (K,Na)NbO_3-based Lead-free piezoceramics

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Journal of the Chinese Ceramic Society 2016年第1期3卷 9-16页

作者： BABA Ryosuke KARAKI Tomoaki FUJII Tadashi Department of Intelligent Systems Design Engineering Toyama Prefectural University

Porous piezoceramics are of interest for applications such as low frequency hydrophones. Porous(K,Na,Li)NbO_3-BaZrO_3-(Bi,Na)TiO_3 lead-free piezoceramics having vertical morphotropic phase boundary composition were fabricated by adding 30 μm-diameter acrylic resins. The ceramic powders were synthesized by a conventional solid-state reaction method and then mixed with the resins. Volume ratios of ceramics to resin were 90:10, 80:20, 70:30, and 60:40. After burning out the resins and binder, the specimens were sintered at 1170–1190 ℃ for 5 h. The porous specimen with 30 vol% acrylic resin had longitudinal acoustic velocity of 4518 m/s, acoustic impedance of 16.44 Mkg/(m^2·s), and hydrostatic figure of merit of 405×10^(-15)m^2/N. The hydrostatic figure of merit was about 4 times of that of monolithic ceramics. Compared with monolithic ceramics, the porous specimen had a better transducer sensitivity for underwater applications.

关键词： porous materials lead-free piezoceramics acoustic impedance hydrostatic figure of merit

MULTI-OBJECTIVE SHAPE OPTIMIZATION FOR piezoceramics

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MULTI-OBJECTIVE SHAPE OPTIMIZATION FOR PIEZOCERAMICS

A NOVEL METHOD FOR EXACT SOLUTIONS OF ELLIPTICAL CRACKS IN PIEZOELECTRICS

第三届全国压电和声波理论及器件技术研讨会

作者： Fang WANG College of Environment and Safety Engineering,Qingdao University of Science and Technology, Qingdao,Shandong 266042,China Michael DELLNITZ Institute for Mathematics,University of Paderborn,Paderborn 33100,Germany

This work first introduces a mathematical model which describes the property of a piezoelectrically excited in resonance under weak electric *** linear equation of motion for a general shape is given and solved *** usual shapes(e.g.a rectangular shape) and unusual ones(e.g.a shape with curved sides) are considered,and the results show that some curved side piezoceramics perform better than those with a rectangular shape when using a linear model for the *** the next step a multi-objective shape optimization problem for the design of piezoelectric actuators is *** objectives,the maximum amplitude(better performance) and the minimum curvature(,simple manufacturing),need to be optimized at the same *** optimization is conducted with a subdivision algorithm based on the software package GAIO and the corresponding Pareto-optimal solutions are obtained for a linear model.

关键词： piezoceramics shape optimization subdivision algorithm multi-objective optimization

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Acta Mechanica Solida Sinica 2005年第4期18卷 326-333页

作者： Xu Jian Chen Mengcheng Noda Nao Aki School of Civil Engineering and Architecture East China Jiaotong University Nanchang 330013 China Kyushi Institute of Technology Kitakyushu shi 804-8550 Japan

According to the constitutive relationship in linear piezoceramics, elliptical crack problems in the impermeable case are reconsidered with the hypersingular integral equation method. Unknown displacement and electric potential jumps in the integral equations are approximated with a product of the fundamental density function and polynomials, in which the fundamental density function reflects the singular behavior of electroelastic fields near the crack front and the polynomials can be reduced to a real constant under uniform loading. Ellipsoidal coordinates are cleverly introduced to solve the unknown displacement and electric potential jumps in the integral equations under uniform loading. With the help of these solutions and definitions of electroelastic field intensity factors, exact expressions for mode Ⅰ, mode Ⅱ and mode Ⅲ stress intensity factors as well as the mode Ⅳ electric displacement intensity factor are obtained. The present results under uniform normal loading are the same as the available exact solutions, but those under uniform shear loading have not been found in the literature as yet.

关键词： piezoceramics elliptical planar crack hypersingular integral equation uniform loading exact solution

Piezoelectric material selection for transducers under fuzzy environment

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Journal of Advanced Ceramics 2013年第2期2卷 141-148页

作者： Gaurav VATS Rahul VAISH School of Engineering Indian Institute of Technology MandiHimachal Pradesh 175001India

Piezoelectric ceramics are extensively investigated materials for transducer *** selection of optimal piezoelectric material for this particular application is a tedious *** depends upon various physical properties,including piezoelectric charge coefficient(d33),electromechanical coupling factor(K_(p)),dielectric constant(ε_(r)),and dielectric loss(tanδ).The classical multiple attribute decision making(MADM)can be used for decision making if these properties are known ***,these properties cannot be expressed by exact numerical values,since they are dependent upon the microstructure and fabrication ***-based MADM approaches can be helpful in such *** this paper,we have determined the ranks and rank indices(for degree of closeness)of important piezoelectric materials using fuzzy VlseKriterijumska Optimisacija I Kompromisno Resenje(VIKOR)***(8/65/35)((Pb_(1-x)La_(x))(Zr_(y)Ti_(1-y))O_(3))and KNN-LT-LS((K_(0.44)Na_(0.52)Li_(0.04))-(Nb0_(.84)Ta_(0.10)Sb_(0.06))O_(3))consecutively are found to be the top-rank piezoelectric *** indicates that KNN-LT-LS can be used on behalf of lead-based piezo-ceramics.

关键词： piezoceramics selection MADM fuzzy approach transducer application

Wind turbine blade health monitoring with piezoceramic-based wireless sensor network

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International Journal of Smart and Nano Materials 2013年第3期4卷 150-166页

作者： Gangbing Song Hui Li Bosko Gajic Wensong Zhou Peng Chen Haichang Gu Department of Mechanical Engineering University of HoustonHoustonTX 77004USA School of Civil Engineering Harbin Institute of TechnologyHarbin 150000P.R.China

In this paper,a piezoceramic-based wireless sensor network(WSN)was developed for health monitoring of wind turbine blades with active sensing *** WSN system has an access point that coordinates the network and connects to a PC to control the wireless *** wireless node functions as an actuator to excite an embedded piezoceramic patch with desired guided *** remaining wireless nodes function as sensors to detect and transmit the wave responses at distributed *** damage status inside the blade was evaluated through the analysis of the sensor *** on wavelet packet analysis results,a damage index and a damage matrix were developed to evaluate the damage status at different *** verify the effectiveness of the proposed approach,a static loading test and a wind tunnel test were performed in the Laboratory of Joint Wind Tunnel and Wave Flume at Harbin Institute of Technology(HIT),*** results show that damage in wind turbine blades can be detected and evaluated by the proposed approach.

关键词： piezoceramics active sensing wireless sensor network structural health monitoring wind turbine blade

Multiobjective Optimal Design of Underwater Acoustic Projector with Porous Piezocomposite Active Elements

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Journal of Applied Mathematics and Physics 2013年第6期1卷 89-94页

作者： A. V. Nasedkin M. S. Shevtsova J.-C. Liu S.-H. Chang J.-K. Wu 1Mathematical Modeling Department Southern Federal University Rostov-on-Don Russia 2Department of Electrical Engineering National Taiwan Ocean University Zhongzheng Taiwan 3Departments of Microelectronics & Marine Engineering National Kaoshiung Marine University Kaoshiung Taiwan

This paper concerns the optimization problem for multilayered ultrasonic transducer with active porous piezoelectric layer. The dependences of the effective moduli for porous piezoelectric material on porosity have been previously obtained and allowed to decrease the number of design variables. The multiobjective optimization problem based on the Pareto-frontier calculation has been solved using the live-link of finite-element (FE) package Comsol Multiphysics with MATLAB.

关键词： Porous piezoceramics Multiobjective Optimization Pareto Frontier Multilayered Acoustic Projector Underwater Applications