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1.
超磁致伸缩材料的热效应严重影响其控制精度.文章分析了超磁致伸缩器系统的热源,采用试验的方法确定了一定条件下的热应变和磁应变;设计了适合超磁致伸缩器的冷却子系统;基于热应变和磁应变试验曲线提出了软件向上补偿方法.  相似文献   

2.
采用IBS法在锡青铜衬底上溅射沉积Sm-Fe非晶态超磁致伸缩薄膜,研究衬底的表面状态和薄膜热处理对Sm-Fe薄膜磁致伸缩性能的影响.实验结果表明,锡青铜衬底状态对Sm-Fe超磁致伸缩薄膜磁伸性能有很大影响.样品经过200℃真空热处理后,100 mT内dλ/dH值从制备态Sm-Fe薄膜的0.71×10-3 T-1提高到2.48×10-3 T-1,薄膜低场磁敏性得到显著提高.  相似文献   

3.
基于大型铁磁材料的磁致伸缩特性是电力设备发生电磁振动的主要因素,提出了一种适用于普通实验室环境的硅钢片磁致伸缩测量系统,设计了能产生外加磁场的螺线管用来激励硅钢片发生形变,运用陶瓷发热片和温度传感器对硅钢片温度进行调节和控制。基于高精度应变电阻片实现对硅钢片形变的测定,通过理论仿真和实验研究,该装置能准确测量饱和状态和不同温度下的磁致伸缩率。为电磁测量实验及电磁振动分析提供了可靠依据。  相似文献   

4.
采用磁致伸缩测试仪测量无取向硅钢片50WW800的磁致伸缩系数,并对不同钢种及不同退火工艺的无取向硅钢片的磁致伸缩系数进行比较,发现磁致伸缩系数存在最大值,且与磁感的大小、退火时间的长短及试样方向等因素密切相关。  相似文献   

5.
介绍了磁致伸缩位移传感器的结构、工作原理及信号特点,利用单片机对位移进行精确的测量,并对磁致伸缩位移传感器的输出模拟信号进行数字化处理,得到准确的数字信号,使得磁致伸缩位移传感器操作简单、互换性好、有效传递数据距离长.  相似文献   

6.
目的:超声导波是一种有潜力的无损检测方法,磁致伸缩换能器是一种重要的导波换能器。利用经典的简正模态展开法分析弹性空心圆柱体在磁致伸缩载荷下的激励响应,包括磁致伸缩局部载荷、轴向阵列载荷和圆周阵列载荷。空心圆柱体在磁致伸缩载荷作用下的扰动分析将为磁致伸缩换能器以及换能器阵的进一步发展提供理论依据。创新点:1.利用简正模态展开方法,讨论弹性空心圆柱体在磁致伸缩载荷作用下的扰动分析和激励响应;2.通过数值仿真和试验研究,验证空心圆柱体在磁致伸缩局部载荷、轴向阵列载荷和圆周阵列载荷作用下不同的激励响应,得到有效的结论。方法:1.通过理论推导,构建典型磁致伸缩换能器数学模型(公式(15)和(17));2.通过理论推导,建立弹性空心圆柱体在磁致伸缩局部载荷、轴向阵列载荷和圆周阵列载荷作用下的波源分析模型(公式(25~26)、(30~31)和(34~35)),求解得到典型载荷形式下的激励响应(图6~8和11~13);3.通过仿真模拟和试验研究,对空心圆柱体在不同磁致伸缩载荷作用下的激励响应进行验证(图14~21)。结论:1.磁致伸缩局部载荷能够激励产生同一族的导波模态,但是不具有良好的频率选择性和相速度选择性,轴对称载荷仅能激励轴对称模态;2.磁致伸缩轴向阵列载荷具有良好的频率选择性和相速度选择性,中心频率和中心相速度取决于阵列单元间距,对导波模态控制非常有益;3.磁致伸缩圆周阵列载荷能够激励周向阶次为阵列单元数整数倍的导波模态。  相似文献   

7.
随着高新技术的发展,集传感、驱动和控制功能于一体的智能材料的研究,具有十分重要的意义,作为主要研究的智能材料有压电材料、电致伸缩材料、磁致伸缩材料等。本文主要介绍了电致伸缩效应、压电效应、磁致伸缩效应的产生机理和当前在工业及日常生活中的应用,并简单探讨了其发展前景。  相似文献   

8.
介绍采用巨磁电阻传感器与配对小磁钢设计组成新型位移传感器,测量材料的磁致伸缩系数,并对自旋阀巨磁电阻(NVEAA002-02)位移传感器以及多层膜巨磁电阻(SS501A)位移传感器的测量结果进行分析比较,得出用多层膜巨磁电阻(SS501A)位移传感器测量磁致伸缩系数时灵敏度较高,结果较准确,对磁致伸缩系数的传统测量方法有明显的改进。  相似文献   

9.
笔者在前人针对硅钢片振动理论研究的基础上,优化了硅钢片由磁致伸缩而产生振动的数学模型。通过计算结果与试验结果的比较,分析影响硅钢片磁致伸缩的主要因素,并提出抑制措施。  相似文献   

10.
根据铁磁材料和亚铁磁材料的磁致伸缩和压磁效应,描述了压磁式传感器理论数学模型,并介绍了磁致伸缩式扭矩传感器和压磁式测力传感器构造及其在工程中的应用。  相似文献   

11.
针对信息显示技术专业的特点,建立了平板显示技术的核心——薄膜晶体管的工艺实验,并且以薄膜晶体管工艺为主线,分模块建立了平板显示技术实验平台,开设了从显示技术基础到显示系统的实验系列.平板显示技术工艺实验平台在教学与科研、基础与创新、教师与学生之间建立起了一座桥梁.  相似文献   

12.
A giant magnetostrictive material (GMM) model is developed based on the hysteretic nonlinear theory. The Gram-Schmidt regression method is introduced to determine the parameters of the model as well as the relation- ship between the material strain and the strength and frequency of magnetic field in the model. Through comparison, it is shown that this regression method has good performance in significance test. Then the model is applied to study the motion law of a circular plate in classical GMM transducer, which helps control the transducer rapidly and accurately.  相似文献   

13.
基于超磁致伸缩材料的非圆曲面形活塞销孔加工新型机构   总被引:2,自引:0,他引:2  
To bear more loads for heavy truck pistons, the shape of heavy truck piston pinhole is often designed as noncylinder form. Current methods cannot meet the needs for precision machining on non-cylinder piston pinhole (NCPPH). A novel mechanism based on giant magnetostrictive materials (GMM) is presented. New models are established for the servo mechanism, GMM, and magnetizing force of the control solenoid to characterize the relationship between the control current of the solenoid and the displacement of the giant magnetostrictive actuator (GMA). Experiments show that the novel mechanism can meet the needs to perform fine machining on NCPPH effectively.  相似文献   

14.
Research on control method for machining non-cylinder pin hole of piston   总被引:1,自引:3,他引:1  
INTRODUCTION With the development of engine power and ro- tational speed, the load of pin hole of piston is more and more heavy. By analyzing the load of common cylindrical pin hole, the load of each part of the pin hole is asymmetric when the engine is working. The stress of inner side is the most and that of the outer side is the least. So, to improve engine performance, people reduce the stress concentration of the inner side of the pin hole by changing the geometric shape and improve …  相似文献   

15.
1 Introduction The giant magneto-i mpedance ( GMI) effect is alarge change of AC i mpedance of soft magnetic con-ductor upon application of an external magnetic field .It has drawn much research attention because of itsprospective applications in high sensitive magnetic sen-sors. GMI materials can be of the forms of homoge-neous wires[1-3], ribbons[2 ,4 ,5], fil ms[3], inhomoge-neous forms of microtubes[6 ,7]and sandwich structuredfil ms[8-10]. Thin fil ms are more preferable for sensorappl…  相似文献   

16.
This study presents a new method to solve the difficult problem of precise machining a non-cylinder pinhole of a piston using embedded giant magnetostrictive material (GMM) in the component. We propose the finite element model of GMM smart component in electric, magnetic, and mechanical fields by step computation to optimize the design of GMM smart component. The proposed model is implemented by using COMSOL multi-physics V3.2a. The effects of the smart component on the deformation and the system resonance frequencies are studied. The results calculated by the model are in excellent agreement (relative errors are below 10%) with the experimental values.  相似文献   

17.
文章通过介绍阻抗匹配原则来分析和研究扩音机与扬声器的配接方法和配接要点,掌握简便正确的使用方法,以便运用好扩音设备,使广播宣传发挥应有的作用。  相似文献   

18.
To understand the vibration noise behaviors of amorphous metal alloy core distribution transformer(AMACDT), a 10 k VA prototype was tested under no-load and short-circuit conditions, respectively. The vibration characteristics were described when rated voltage was applied to the secondary side, and the primary side was connected with different load resistances. The largest amplitude positions on the upper bracket and tank surfaces were recorded by vibration sensors arranged on the surface. A data-acquisition platform was set up for signal measurement. The vibration amplitude related to frequency was discussed, and experimental results indicated that the position with the largest amplitude accrued in the middle of the upper bracket and tank surface, at phases a and c, respectively. The experimental results suggest that magnetostrictive and electrodynamic forces play a major role in exciting the vibration noise. At the same time, some rib-reinforcements were welded on the upper bracket and tank surfaces to lessen the vibration energy, which reduced the noise.  相似文献   

19.
Ag/AgCl electrode has been prepared using pressed powder techniques. In order to verify the feasibility of this type of electrode used as detecting electric field generated by vessels in seawater, its characteristics of DC resistance, low frequency AC impedance, and receiving impedance in artificial seawater have been studied by polarization measurements, low frequency electrochemical impedance spectra, the open and short circuit cell conditions. The results show that the electrode can keep a low resistance when it responses the weak electrostatic field in seawater. The AC impedance of the electrode decreases as the frequency of the signal increasing. The receiving impedance decreases when the frequency of external field increases too. The valid detection bandwidth is determined by the properties of the impedance and the reactions occurring on the surface of the electrode.  相似文献   

20.
用超磁致伸缩材料做成的换能器具有输出力大、响应速度快的特点,这就要求其驱动电源瞬间能输出较大的电流以形成强磁场.由于该换能器是处于间歇工作状态,利用电容的储能原理制成的驱动电源能满足要求,其关键的难点是储能电容的容量要与换能器线圈的参数相匹配,才能得到良好的效果.可用Matlab软件,通过计算机辅助分析的方法确定储能电容的参数值.储能电容的充放电转换开关可用继电器或场效应管实现.实验表明,该电源可用小型的充电电池供电,并具有连续工作时间长,工作可靠,瞬间输出功率大,体积小、重量轻的特点,特别适合野外使用.  相似文献   

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