磁流变阻尼器集成式电磁活塞结构设计及磁路分析

对传统的磁流变阻尼器活塞结构进行了改进设计,提出了集成式电磁活塞结构,即将整个磁路集中于活塞部分,并建立了基于流动工作模式的理论分析模型。针对磁路模型进行了2D、3D有限元数值仿真计算,利用2D仿真分析了相关结构参数对磁路性能的影响规律,结合3D磁路仿真完善并验证磁路设计的合理性;根据提出的磁路结构研制磁流变阻尼器样机,通过电测示功机进行示功及速度特性试验,表明该阻尼器具有优良的磁致阻尼性能,证明了集成式电磁活塞结构设计的有效性。

基于电容测试的磁流变弹性体磁控电学特性研究

磁流变弹性体(MRE)主要是由橡胶基体与软磁颗粒组成的复合材料,其最大的特点就是在外磁场作用下拥有良好的磁控特性。以MRE作为电介质设计试验电容器,建立外加磁场可调的电容试验测试系统,通过在磁场作用下对电容的测试研究MRE的磁控电学特性。研究结果表明,以MRE为电介质的电容器具有优良的磁控电容特性,电容的变化与磁场的变化成正比,即体现了MRE的介电常数与外磁场大小存在正比关系。另外,MRE中软磁颗粒含量、增塑剂的含量及粘度、制备条件的不同对MRE电容器的磁控电容特性也有显著的影响。

Magnetic field-dependent inductance properties based on magnetorheological elastomer

Magnetorheological(MR)materials are a class of smart material,whose the mechanical/rheological state can be controlled under a magnetic field.Magnetorheological materials are typically fluids,gels,or elastomers.In this study,anisotropic and isotropic magneto-rheological elastomer(MRE)samples were fabricated using a silicone rubber matrix with carbonyl iron particles as filler particles.The magnetic field-dependent inductance properties of these samples were studied using inductors specially designed for the analysis.The effect of the filler particle content,fabrication conditions,and inductance properties were characterized using a self-built system in both constant and transient magnetic fields.These factors show a significant effect on the inductance properties of the MRE inductor under an applied magnetic field.The anisotropic MRE inductor was more sensitive than the inductor based on an isotropic MRE.Owing to the presence of a constant magnetic field,the inductance value of the MRE inductor decreased with an increase in the external magnetic field.An attempt in elucidation of the mechanism is reported here.This study may enable the MRE to be widely used in practical applications such as monitoring magnetic field or detecting the filler particle content inside MR materials.

基于磁致变刚度的微振动隔振器动态特性研究

磁敏弹性体是智能材料家族中的新成员,其储能模量(刚度)可由外加磁场控制,利用磁敏弹性体的这一特性,以其作为变刚度元件设计了面向精密设备的磁致变刚度微振动隔振器。采用扫频与定频试验探讨了微振动隔振器动态隔振特性。结果表明,在励磁电流激励的磁场控制下,磁敏弹性体刚度随激励磁场实时变化,导致系统产生移频效应,使隔振器在宽频范围内具有良好的隔振效果,尤其共振区的隔振效果最佳。