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 共查询到18条相似文献,搜索用时 171 毫秒
1.
黄舒 《中国科技信息》2007,(19):269-269
本文主要介绍了钛酸钡压电陶瓷,PbTiO3—PbZrO3系以及PbTiO3压电陶瓷的发展,同时也对目前研究的无铅压电陶瓷、陶瓷聚合物压电复合材料、纳米压电陶瓷进行了综述,指出了压电陶瓷将向着无铅化、纳米化、多种聚合物复合的发展趋势。  相似文献   

2.
概述了压电陶瓷的基本特性,着重介绍了圆片型压电陶瓷的谐振特性测量。  相似文献   

3.
综述了压电陶瓷低温烧结研究的必要性以及目前压电陶瓷低温烧结所采用的主要方法.  相似文献   

4.
功能陶瓷研究进展与发展趋势   总被引:13,自引:0,他引:13       下载免费PDF全文
简要评述了陶瓷基板,微波介质陶瓷,铁电压电陶瓷,半导体陶瓷,铁电薄膜和智能材料等功能陶瓷的研究进展和发展趋势,对我院功能陶瓷的发展提出了一些建议。  相似文献   

5.
对国内外压电陶瓷材料的最新应用情况及最新研究进展做一扼要的综述,同时对近年来压电陶瓷制备技术的进展也进行了简要的评述,并对压电陶瓷材料未来的发展动态进行了展望,目的在于使相关研究人员能注意到该领域新的发展状况及亟待解决的问题,为我国实现21世纪的陶瓷工业强国而奋斗.  相似文献   

6.
BNT无铅压电陶瓷体系的设计及制备工艺研究   总被引:1,自引:0,他引:1  
本文采用传统陶瓷工艺,制备得到Bi0.5(Na1-x-yKxLiy)0.5TiO3(简称BNKLT)无铅压电陶瓷,运用X射线衍射、扫描电子显微镜对其进行了分析表征;通过压电、介电性能的对比,讨论了烧结温度对BNKLT陶瓷的影响:运用热分析及X射线衍射等手段,确定了粉体的热处理温度,并讨论了烧结温度对BNKLT陶瓷性能的影响;通过最终所得陶瓷的性能对比,确定制备的较优工艺参数.  相似文献   

7.
陈骏凯  靳晓雄 《中国科技信息》2006,(16):107-109,166
基于国内对汽车车内噪声控制标准的提升,运用目前国内外对噪声主动控制方面的研究成果,结合汽车自身特点,阐述了利用压电陶瓷对车内噪声进行主动控制的研究;并根据车内声学模态对压电陶瓷优化配置方法和基于智能模糊的控制策略进行探讨,最后通过对轿车车内噪声控制试验验证这种主动控制方法。  相似文献   

8.
压电陶瓷式柴油机电控ECU日趋复杂。CPLD用硬件原理图输入法实现控制逻辑在线编程、在线修改。在压电陶瓷ECU设计中用CPLD实现发动机选缸逻辑,充电、放电预驱动逻辑、油泵驱动逻辑。实验证实,使用CPLD前、后,ECU实现相同的功能情况下,使用CPLD的控制单元PCB面积变小,控制逻辑实现更加灵活、保密。  相似文献   

9.
利用压电陶瓷换能器等效成LC电路的方法,推导出发出最大能量时的谐振频率。通过改变电路的参数值可得到不同的频率值,结果表明电路等效法是高效的方法。  相似文献   

10.
分析了滚珠丝杠副的原理及结构形式。详细阐述了适合高速化数控机床的滚珠丝杠副形式。提出了一种新的滚珠丝杠副的调隙和预紧方式—连续可调预紧装置。运用压电陶瓷传感器与压电驱动器结合的方法。通过此种方法可以直接测量预紧力,随时精确地补偿因磨损而增大的间隙。提高了数控机床的轴向刚度和定位精度。  相似文献   

11.
为了提高电火花加工的稳定性,提出了椭圆运动微驱动技术。基于李萨如图形的原理,利用压电晶体的逆压电效应进行工作.并进行了驱动本体和驱动电路设计。实验结果表明,椭圆运动驱动技术具有频率响应快、步距小和设计简单的优点。  相似文献   

12.
This study describes the high-precision positioning control of a system with asymmetric hysteresis. A switching system concept is adopted to describe the Preisach-type hysteresis, and a systematic modeling procedure is established to obtain the parameters of the system. A piezoelectric actuator system driven by a voltage amplifier is used to verify the modeling accuracy. A control structure, comprising a feedforward controller and a PD-type feedback controller, is used to realize the high-precision positioning control of the piezoelectric actuator driven stage. To enhance tracking control, a high-frequency modified term is incorporated into the hysteresis model. The experimental results confirm that the addition of this modified term reduces the tracking error and prevents the controlling energy from being saturated.  相似文献   

13.
The problem of positioning of actuators and sensors on smart materials has been a point of interest in recent years. This is due to the fact that in many practical applications there are limitations in space, weight, etc. of the smart structures, which make the problem of positioning more complex. In addition, it is required that the actuators/sensors have the best possible performance. The development of smart structures technology in recent years has provided numerous opportunities for vibration control applications. The use of piezoelectric ceramics or polymers has shown great promise in the development of this technology. The employment of piezoelectric material as actuators in vibration control is beneficial because these actuators only excite the elastic modes of the structures without exciting the rigid-body modes. This is important since very often only elastic motions of the structures are needed to be controlled. The purpose of this paper is to introduce a novel approach developed for optimizing the location of piezoelectric actuators for vibration suppression of flexible structures. A flexible fin with bonded piezoelectric actuators is considered in this study. The frequency response function (FRF) of the system is then recorded and maximization of the FRF peaks is considered as the objective function of the optimization algorithm to find the optimal placement of the piezoelectric actuators on the smart fin. Three multi-layer perceptron neural networks are employed to perform surface fitting to the discrete data generated by the finite element method (FEM). Invasive weed optimization (IWO), a novel numerical stochastic optimization algorithm, is then employed to maximize the weighted summation of FRF peaks. Results indicate an accurate surface fitting for the FRF peak data and an optimal placement of the piezoelectric actuators for vibration suppression is achieved.  相似文献   

14.
孙建  韩庆邦 《科技通报》2012,28(2):55-57
氧化物陶瓷热电材料是一种有利于环保的新型能源转换材料.本文通过对氧化物陶瓷热电材料性能和影响因素地分析,特别是针对物性对热电性能的影响,结合实践提出了把氧化物热电材料做成多晶材料、材料的纳米结构复合化、搀杂修饰材料的能带结构等提高其性能的具体途径,用以指导具体的应用,希望具有启发意义.  相似文献   

15.
The Franklin Institute, Philadelphia, Pennsylvania, awarded the Benjamin Franklin Medal in Engineering to Robert E. Newnham for his invention of multiphase piezoelectric transducers and their spatial architecture which revolutionized the field of acoustic imaging. The background and significance of his research is presented. Attention is focused on the impact his research prompted in the field of medical imaging, in particular non-invasive, real-time visualization of internal tissue and organs of human body using ultrasound energy. Societal impact of Dr. Newnham's work is also pointed out.  相似文献   

16.
Due to growing concern for the environment and human health, searching for high-performance lead-free piezoceramics has been a hot topic of scientific and industrial research. Despite the significant progress achieved toward enhancing piezoelectricity, further efforts should be devoted to the synergistic improvement of piezoelectricity and its thermal stability. This study provides new insight into these topics. A new KNN-based lead-free ceramic material is presented, which features a large piezoelectric coefficient (d33) exceeding 500 pC/N and a high Curie temperature (Tc) of  ∼200°C. The superior piezoelectric response strongly relies on the increased composition-induced structural flexibility due to lattice softening and decreased unit cell distortion. In contrast to piezoelectricity anomalies induced via polymorphic transition, this piezoelectricity enhancement is effective within a broad temperature range rather than a specific small range. In particular, a hierarchical domain architecture composed of nano-sized domains along the submicron domains was detected in this material system, which further contributes to the high piezoelectricity.  相似文献   

17.
We used two simple control laws based on linear velocity and cubic velocity feedback to suppress the high-amplitude vibrations of a structural dynamic model of the twin-tail assembly of an F-15 fighter when subjected to primary resonance excitations. We developed the nonlinear differential equations of motion and obtained an approximate solution using the method of multiple scales. Then, we conducted bifurcation analyses for the open- and closed-loop responses of the system and investigated theoretically the performance of the control strategies. The theoretical findings indicate that the control laws lead to effective vibration suppression and bifurcation control. Furthermore, we conducted experiments to verify the theoretical analysis. We built a digital control system that consists of a SIMULINK modeling software and a dSPACE controller installed in a personal computer. Actuators made of piezoelectric ceramic material were used. The results show that both laws are effective at suppressing the vibrations. To compare the performance of both techniques, we calculated the power requirements for a simple system.  相似文献   

18.
景德镇陶瓷历史文化旅游资源非常丰富,但从景德镇所取得的旅游业绩看,旅游资源的开发却不甚理想,强大的旅游资源优势还没有完全转化为相应的旅游经济优势。本文分析了景德镇陶瓷历史文化旅游资源开发中存在的问题,并提出相关策略。  相似文献   

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