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31.
为了提高直线超声电机的输出性能,研制了纵弯复合模态“工字形”直线超声电机,对“工字形”弹性体的几种复合振动模态及其驱动方案进行了分析,确定了振子的工作模态。完成了“工字形”振子的结构设计,利用ANSYS软件对“工字形”压电振子进行了优化设计,确定了定子各结构参数。纵向伸缩振动模态固有频率和弯曲振动模态固有频率分别为33.07kHz和33.08kHz,频率差8Hz。根据优化设计结果,试制了原理样机。对样机的输出性能进行了实验研究。实验结果表明:当驱动频率为31.10 kHz,激励电压峰峰值为250V时,电机动子Vmax为240mm/s;驱动力Fmax为0.5N。 相似文献
32.
Xiuming Li Quan Xu Guangtao Wu Baozhi Cheng Yonghao Liu Rui Yang 《Integrated ferroelectrics》2017,183(1):36-42
Surface acoustic wave propagation in a 0.955Pb (Zn1/3Nb2/3)O3-0.045PbTiO3 multidomain single crystal poled along [001]c has been analyzed theoretically using Christoffel wave equations. From the measured experimental data, the orientational dependence of surface acoustic wave phase velocities, electromechanical coupling coefficients and power flow angles was calculated. The results showed that surface acoustic wave propagations of 0.955Pb (Zn1/3Nb2/3)O3-0.045PbTiO3 are poor than 0.93Pb(Zn1/3Nb2/3)O3-0.07PbTiO3 crystal slightly. However, the 0.955Pb (Zn1/3Nb2/3)O3-0.045PbTiO3 single crystals have higher rhombohedral-tetragonal phase transition temperature and much stabler electromechanical properties. This may expand applications range of SAW devices. 相似文献
33.
Control of structural vibrations has significant applications in manufacturing, infrastructure engineering, aerospace engineering and various consumer products. In last two decades, considerable attention has been focused to suppress structural vibrations using active vibration control technique. Various researchers have proposed various optimization criteria for optimal placement of piezoelectric patches over a smart structure to suppress vibrations using various optimization techniques. This paper presents a review of various optimization criteria and techniques that have been used by various researchers in the field of smart structures. Mathematical expressions of objective functions of twelve optimization criteria have been presented and their justifications have been reasoned. Step by step procedures of commonly used optimization techniques have also been presented. 相似文献
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基于自主研制高精度数字化相移干涉仪的需求,针对干涉仪的压电陶瓷移相器设计了一种高压放大电路。通过双极性运算放大器OP07构成低噪声,非斩波稳零的低压放大电路与中功率线性三极管MJE340和MJE350构成高压放大电路进行直流耦合,结合反馈网络,功率放大电路,滤波电路以及限流保护电路,将计算机输出的0~5 V低电压的移相控制信号稳定线性放大到-30 V~+130 V范围,且输出低至10 mV 峰值的纹波,满足压电陶瓷移相器的高压驱动控制要求和相移干涉仪的高精度移相测量的要求。 相似文献
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探讨了直角域附近一圆形衬砌对压电材料的反平面动力学行为的影响.通过利用镜像法对直角域情况进行等效处理到全空间中,在复数域中利用衬砌周围的边界条件构造方程求解未知系数,并通过编程进行最终的数值计算得出压电材料在衬砌周围的动应力和电场集中系数.在数值计算中,重点讨论了衬砌和基体为不同材料、衬砌和基体电极化方向相同和不同时,它们随压电材料物理系数、结构几何参数,以及入射波的频率变化的计算结果.结果表明,在SH波的作用下,压电材料在衬砌周围的动应力集中系数和电场集中系数都有一定的相似性,并且沿衬砌周围有规律的分布,然而在入射波的频率较低时二者的值相对较大,同时计算结果还与全空间衬砌下的计算结果有一定的相似性. 相似文献
39.
Shuai Yang Mingwen Wang Lu Wang Jinfeng Liu Jie Wu Jinglei Li Xiangyu Gao Yunfei Chang Zhuo Xu Fei Li 《Journal of the American Ceramic Society》2022,105(5):3322-3330
Textured piezoelectric ceramics, such as textured Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT) ceramics, have attracted considerable attention from both academia and industry, as they possess crystal-like piezoelectric properties, high composition homogeneity, and low manufacturing cost. However, the main difficulty with the textured piezoelectric ceramics is the presence of BaTiO3 (BT) templates, which greatly reduces their piezoelectricity and phase transition temperature. Thus, it is highly recommended to fabricate textured piezoelectric ceramics using as few templates as possible. Here, we successfully fabricated high-quality <001>-textured PMN-28PT ceramics (texturing degree of 99%) by using an extremely small amount of BT templates (1 vol.%) with the help of CuO/B2O3 sintering aids. The textured PMN-28PT ceramic exhibits 80% piezoelectric coefficient (d33 ∼ 1200 pC/N), 96% electromechanical coefficient (k33 ∼ 88%) and the same temperature stability (Trt ∼ 100, Tc ∼ 150°C) when compared to its single crystal counterpart. In addition, by using an alternating current electric field poling (AC-poling), the piezoelectric coefficient d33 and dielectric permittivity ε33 of the textured PMN-28PT ceramics were further enhanced around 5–8%. It is believed that the advantages of high electromechanical properties, low cost, and easy mass production of textured PMN-28PT ceramic will make it a promising candidate for advanced electromechanical devices. 相似文献
40.
Moolchand Sharma Tanisha Singhal Rahul Vaish 《Journal of the American Ceramic Society》2022,105(5):3165-3176
A 0.5(Ba0.7Ca0.3)TiO3–0.5Ba(Zr0.1Ti0.9)O3 (BCT-BZT) ceramic was studied for photocatalysis and piezocatalysis effects using dye degradation (methylene blue, rhodamine B, and methyl orange) and bacterial (Escherichia coli) disinfection from aqueous solution. To examine the effect of ferroelectric polarization, BCT-BZT powder was poled using the corona poling technique. Same time, BCT-BZT was converted into Ag/BCT-BZT composites as Ag induced surface plasmon resonance effect during photocatalysis. Piezocatalysis performance was assessed for dyes mineralization under ultrasonication. There was a significant impact of silver nanoparticles on the photo/piezocatalysis performance of BCT-BZT. Similarly, electric poling has also played a positive role in improving the photo/piezocatalysis in view of various dye degradation. These samples also showed effective antibacterial performance. 相似文献