一种人体能量收集系统的研制

为实现利用压电材料收集人体能量,将其转化成电能在某些特殊应用领域替代电池或自动为电池充电的目的,我们设计了一种人体能量收集系统,它可以在人行走过程中产生电能,该机构被安装在人腿的膝盖部位,选择性地在腿部摆动结束阶段连续地按压压电陶瓷片参与发电,它还能帮助关节完成减速动作,非常适合给假肢或者其他便携式医学设备充电。     

PZT及掺La~（3＋）、Nb~（5＋）PZT的性能初探和态密度计算

用固相化学反应陶瓷烧结法制备了ＰＺＴ及掺Ｌａ３＋、Ｎｂ５＋的ＰＺＴ压电陶瓷片，利用ＸＲＤ、ＸＰＳ现代测试手段分析了样品的结构和性能，并测试了其压电性能。从理论上阐述了掺杂Ｌａ３＋、Ｎｂ５＋离子对ＰＺＴ样品的性能影响。用量子化学计算方法计算了样品的电子态密度．并将计算结果与ＸＰＳ测试结果作比较。     

PZT/PVDF压电复合材料微观结构与性能研究

采用溶液混合法制备 PZT/ PVDF压电复合材料。首先用固相法制备出适合溶液混合的 PZT陶瓷粉末 ,并且通过陶瓷粉末对 PVDF的吸收量选择乙醇为 PVDF的溶剂进行混合 ,然后烘干制备出 PZT/ PVDF复合粉末 ,再成型极化。实验结果表明这种复合方法提高了 PZT陶瓷颗粒在 PVDF有机基体中的分散度 ,使制得的材料内部均匀 ,结构致密 ,从而提高了 PZT/ PVDF压电复合材料的压电和介电性能。     

基于压电陶瓷的交通传感器的输出特性研究

设计并制备了以PZT、PLMN压电陶瓷为敏感材料的交通传感器,比较研究了单调荷载、疲劳荷载作用下的输出特性,以及荷载作用时间、环境温度对两种传感器输出的影响。试验结果表明,虽然两种传感器在疲劳荷载后应力-输出电压输出特性和初始时比较基本没有变化,但基于PZT型压电陶瓷的交通传感器在-20～60℃温度范围内输出与荷载有很好的线性关系,且在荷载作用时间小于0.1 s时输出受荷载作用时间影响小,因此具有更好的输出特性。     

热处理PZT对PZT/PVDF复材电性能的影响

用高温处理PZT陶瓷粉末与PVDF制成压电复合材料,研究了高温处理PZT对复合材料的微观结构、极化特性、压电和介电性能的影响．结果表明：高温处理PZT制备的复合材料孔隙少,其剩余极化明显提高,提高了复合材料的压电系数和介电常数。     

Dielectric and Piezoelectric Properties of 0-3 PZT/PVDF Composite Doped with Polyaniline

Lead zirconate titanate （ PZT ） / polyvinylidene fluoride （PVDF） 0-3 piezoelectric composites doped with polyaniline （PANI） were obtained by hot-press method. The polarization properties of the composites were characterized by XRD and P- E hysteresis loops at room temperature. And the dielectric and piezoelectric properties were also measured. The results show that the poling of PZT could be effectively carried oat and the dielectric constant e, and dissipation tanδ increase monatonously by increasing the volume fraction of PANI in the composite. The piezoelectric constant d33, and the planar electromechanical coupling factor kp increase while the mechanical quality factor Qm decreases with the increase in the content of PANI. The d33, kp and Qm show the extremum values at 8 vol%-10 vol% PANI.     

用于模拟声发射信号的PZT柱状相位调制器设计

为了便于在实验室进行管道泄漏实验,通过PZT柱状相位调制器的逆压电效应模拟泄漏声发射信号,结合压电方程和机电等效原理推导了PZT柱状相位调制器的传递函数,并设计了PZT柱状相位调制器,同时进行了数值模拟．结果表明,设计的相位调制器可有效模拟低于25kHz的泄漏声发射信号．     

周边简支空心压电圆板表面均载弯曲

本文利用横观各向同性压电材料的通解和所构造的三个调和函数,给出了受均布载荷的周边简支空心圆板的解析解,退化得到实心圆板的解,比较了ＰＺＴ－４实心圆板和ＰＺＴ－４有相同弹性常数的横观各向同性圆板的中心挠度和弯矩。     

不同铅气氛对PMSZT压电陶瓷机电性能的影响

采用固相烧结法制备了三元系压电陶瓷Pb0.98Sr0.02（Mn1/3Sb2/3）x（Zr0.5Ti0.5）1-xO3（0%〈x〈0.1）（PMSZT）,研究了铅气氛和非铅气氛保护条件烧结对其相结构、微观结构、介电性能以及压电性能的影响．实验结果表明：在烧结温度1100-1300℃范围内,铅气氛保护烧结的试样其综合性能优于非铅气氛保护烧结的试样．铅气氛保护条件下于1200℃得到最佳性能：εr=1717、d33=301、Kp=0．55、tanδ=0．42％、Qm=1453．     

Harvesting energy from asphalt pavement by piezoelectric generator

This paper presents the way to harvest mechanical energy from asphalt pavement by piezoelectric generator. Results show that the potential energy in asphalt pavement can be up to 150 kW/h per lane per kilometre. Part of the mechanical energy can be harvested by piezoelectric transducers. The performance of seven typical transducers is examined through finite element analysis. Results show that PZT piles and multilayer, cymbal and bridge can work in asphalt pavement environment. PZT piles and multilayer have higher energy converting rate, However, the total harvested energy is small if these transducers are embedded directly in pavement. A prototype pavement generator is developed using PZT piles to increase the harvested energy. The generator can harvest more than 50 kW/h energy from the pavement under heavy traffic. 8-16 PZT piles are recommended for one generator. Round shape is suggested for the PZT piles to reduce the concentration of stress. And multilayer structure is recommended for PZT piles to decrease the electric potential of generator. The generator can be extended as sensor in the asphalt pavement, which can be used to monitor the traffic, pavement stress and temperature.     

界面缺陷对压电薄层复合结构中Love波的影响

基于剪切弹簧模型,建立考虑界面缺陷情形的弹性基底上覆盖压电薄层的复合结构中Love波的频散方程,并研究界面缺陷对Love波传播特性的影响,给出铝基底上覆盖PZT4压电薄层复合结构中Love波的频散曲线.数值结果表明:(1)对于长波情形,不同缺陷程度复合结构的Love波一阶模态的相速度均趋于弹性基底层的剪切波波速,而对于短波情形,则趋于压电薄层的Bleustein-Gulyaev(B-G)波波速;(2)界面缺陷的存在总是降低该复合结构内Love波的相速度,在一些特殊频率范围,Love波的相速度对界面缺陷非常敏感;(3)界面缺陷对压电层内的机械位移模态和电势模态有显著影响,且影响最大区域出现在界面附近.     

基于显微视觉的宏/微双重驱动微动台的自动标定

提出了基于压电技术的微操作系统的自动标定方法,采用混合式步进电机直接驱动的宏动平台,实现系统大行程宏动定位,安装在宏动平台上的压电陶瓷驱动的微动平台和精密光栅,实现亚微米级的分辨率和定位精度,通过以上两部分实现定位机构的全闭环反馈控制,采用显微视觉反馈获取微动台操作器在图像中的位置信息进行标定。实验结果表明:系统的动态和稳定性能良好,自动标定运算速度快,运行速度达到11 frame/s,实现了对系统的精确标定,标定精度达到0.1μm。     

PZT压电陶瓷液相低温烧结技术的研究进展

阐述了PZF压电陶瓷烧结过程中的液相传质机理及实现液相烧结的主要途径.综述了PZY压电陶瓷材料的液相低温烧结研究方向与进展.     

Design and optimization of the piezoelectric micromechanical ultrasonic transducer with an AlN thin film

Because existing ultrasonic transducers mostly use PZT and ZnO materials as piezoelectric thin films, while the PZT contains lead and ZnO has the problem of contaminating CMOS manufacturing, a piezoelectric ultrasonic micromechanical transducer with circular bi-laminate bending vibration which uses the aluminium nitride as the piezoelectric layer is designed. The working principle of the transducer is analyzed, the finite element model is established, and the finite element simulation is carried out for the size parameters of the transducer. It is found that the resonant frequency of the transducer is proportional to the thickness of each layer and inversely proportional to the square of the radius of the transducer; when the radius of the upper electrode is about 65% of the radius of the transducer, the resonant amplitude of the transducer is the largest; when the thickness ratio of the silicon and the aluminum nitride of the piezoelectric layer is about 0.6, the resonant amplitude is also the largest. The optimized transducer is simulated and compared with the original model. The results show that the working frequency in air is 9.21MHz, the electromechanical coupling coefficient increases from 21.44% to 27.16% in air and from 3.55% to 11.93% in water. These conclusions provide basic data for the research on the medical imaging probe.     

Enhanced piezoelectric properties of Nd^3＋ doped nano-lead zirconate titanate piezoelectric ceramics

Nd^3＋ doped lead zirconate titanate （Pb1-3x/2NdxZr0.52Ti0.48O3, PNZT） nanopowders were prepared through a modified sol-gel method. The effects of Nd^3＋ doping on the microstructures and properties of PNZT ceramics have been studies. The grain sizes of the perovskite PNZT nanopowders were about 100nm and the lattice distortion of the PNZT increased with the content of Nd^3＋ up to 9 mol%. The dopant of Nd^3＋ resulted in the decrease of crystal lattice parameter a and the obvious increase of c and c/a, which effectively improved the sintered densification and activity of the PNZT ceramics. Due to lead vacancies caused by the doping of Nd3^＋ in the PZT, the piezoelectric constant, electromechanical coupling coefficient and dielectric constant observed were much higher than the monolithic PZT.     

压电相体积分数对1-3 型压电复合材料的性能影响

采用有限元软件仿真研究了不同的压电相体积分数对1-3 型压电复合材料性能的影响, 并进行了实验验证。结果表明: 当压电相体积分数按照47% 、52% 、68% 、74% 、100% 变化时, 串联谐振频率和并联谐振频率均随压电相体积分数增大而增大; 机电耦合系数在压电相体积分数为52% 时获得最优值0.698; 复合材料的频率常数、密度、纵波声速和声阻抗均随着压电相体积分数的增大而增大。有限元仿真与实验结果较为一致。该材料有望用于制备高性能的无损检测用超声换能器。     

Structure of Pb(Zr,Ti)O<Subscript>3</Subscript>(PZT) for Power Ultrasonic Transducer

To improve the performance of ultrasonic transducer, the samples of PZT were improved by doping. The doped PZT was observed and analyzed from the following aspects: the crystal phase structures, the surface morphologies and the dielectric constant. According to the transducer parameter requirements for ultrasonic machining, there are also requirements for the parameters of piezoelectric ceramics. The high performance PZT was prepared by doping the elements of Ga, Ba, Nb, Sn, and Sr in PZT. The doped PZT is suitable for power ultrasonic machining at 20 kHz through analysis using X-ray diffraction (XPD), a scanning electron microscope (SEM) and LCR meter. Therefore, the excellent performance of transducer for power ultrasonic machining is guaranteed.     

Structure of Pb(Zr,Ti)O_3(PZT) for Power Ultrasonic Transducer

To improve the performance of ultrasonic transducer, the samples of PZT were improved by doping. The doped PZT was observed and analyzed from the following aspects: the crystal phase structures, the surface morphologies and the dielectric constant. According to the transducer parameter requirements for ultrasonic machining, there are also requirements for the parameters of piezoelectric ceramics. The high performance PZT was prepared by doping the elements of Ga, Ba, Nb, Sn, and Sr in PZT. The doped PZT is suitable for power ultrasonic machining at 20 kHz through analysis using X-ray diffraction(XPD), a scanning electron microscope(SEM) and LCR meter. Therefore, the excellent performance of transducer for power ultrasonic machining is guaranteed.     

新型压电精密步进旋转驱动器

提出一种新型的压电精密步进旋转驱动器。该驱动器采用仿生运动的原理,以定子内箝位的方式和均布薄壁柔性铰链微变形结构,解决了以往压电精密驱动器箝位不牢固、旋转步进频率较低、行程小、分辨率低、速度低、输出不稳定等问题。研制的精密旋转驱动器能够实现高频率(30 Hz)、高速度(380μrad/s)、大行程(>270°)、高分辨率(1μrad/step)、且输出稳定,大幅度提高了压电步进旋转驱动器的驱动性能。该驱动器在精密运动、微操作、光学工程、精密定位等精密工程中有广阔的应用前景。     

SCNN无铅压电陶瓷的制备和特性研究

为制备高性能的无铅压电陶瓷,在传统工艺下,制备了Ca_xSr_(2-x)NaNb_5O_(15)陶瓷各组分的样品,研究了压电介电性能随组分的变化.结果表明:在x=0.14附近Ca_xSr_(2-x)NaNb_5O_(15)材料具有较好的压电和介电性能.该材料有2个相变点,一个接近280℃,另一个在-20℃附近,具有明显的介电弛豫现象.X射线衍射和Raman光谱实验表明该材料是四方钨青铜结构,Ca~(2+)替代Sr~(2+)引起了晶格畸变,从而导致物理性能的提高.电镜扫描照片显示瓷体致密.