电流变液力缓速器的研究

针对汽车辅助制动系统的需求,研制开发车用电流变液力缓速器.为此,研制开发了可控高压电源,配制了电流变液,在充分研究电流变液的粘度特性后,进行了电流变液力缓速器制动特性的研究.试验结果表明:同传统液力缓速器相比电流变液力缓速器具有结构简单,可控性好的特点;但与同体积的电涡流缓速器相比电流变液力缓速器的制动力矩只有其1/3左右,但损耗的电源功率只有其1/100左右.     

乳状电流变基液及其对材料性能的影响

研究试制了乳状电流变基液，以二甲基硅油为基体，二甲基亚砜作添加剂，在超声波的作用下使二甲基亚砜分散于硅油中形成稳定的乳状液，测试了该乳液的介电常数，电导率及介电损耗。以此乳液作基液，与稀土改性TiO2和BaTiO3等固体颗粒配成电流变液，并对其流变性能进行测试。实验结果表明：用该乳液作基液配制的电流变液化用纯硅油作基液配制的电流变液介电性能有较大的改善，电流变性能显著提高。     

复合颗粒电流变液的制备及其性能

制备了ＳｉＯ２／Ｐ（ＭＭＡ－ＭＡＡ）微囊复合颗粒电流变液,测试了该电流变液的力学性能和材料性能。结果指出：这种复合颗粒电流变液的稳定性有较大的提高;剪切强度随外加电场强度的增大而增大。     

Sol-Gel Preparation of Graphite/TiO2 Composite Particles and Their Electrorheological Effect

Graphite/TiO2 composite particles were obtained by sol-gel technique in this paper. The structure and characteristic of the composite particles are analyzed by XRD, SEM and TG-DTA. The electrorheological properties of the ER fluid containing the particles were measured by a Couette-type rheometer under shear rates of 1～136 s-1 and AC electric fields of 0～3 kV/mm. The experimental results show that the leaking current density of the ER fluid is higher than that of pure titanium dioxide particles dispersed in damping oil. The shear yield stress of the ER fluid increases with increasing electric field and exhibits a typical Bingham flow behavior. The suspension demonstrates an excellent ER performance (τ/τ0=1200) compared with conventional ER fluids (τ/τ0 ≤500). The sedimentation of the ER fluid is improved obviously due to the coating effect of the particles.     

电流变液添加剂的研究

从能量角度定量研究了添加剂对电流变液屈服应力的影响，提出了添加剂作用的极化模型。并用液晶材料作为添加剂进行实验，所得结果与极化模型理论相一致。     

ER Smart Fluids: Properties and Applications

ER fluid is one of the popular materials used in smart materials and structures (SMS). In thispaper, several ER fluids were synthesized. The static and dynamic mechanic characteristics weremeasured and discussed. The application of ER fluid on a sandwich beam featuring ER fluidapplied to vibration control was investigated.     

The influence of solid-phase concentration on the performance of electrorheological fluids in dynamic squeeze flow

The yield stress of electrorheological (ER) fluids increases by orders of magnitude when electric field is applied across them. In the absence of the field, ER fluids behave as Newtonian fluids. This paper is concerned with an experimental investigation to determine the rheological performance of ER fluids, consisting of a dielectric liquid carrier with a range of solid-phase concentration. The ER fluid was contained in a squeeze cell, which during motion subjects the fluid to both compressive and tensile loading. The results were analysed in terms of the capacity for the transmission of imposed forces across the fluid and showed a great dependence on the applied D.C voltage and the weight fraction of the dispersed solid-phase. In addition, the implications of the results to vibration control, where the ER fluid is employed in an engine mount, are discussed.     

Material characteristics of an ER fluid and its influence on damping forces of an ER damper Part I: material characteristics

This paper presents experimental results on material properties of an electro-rheological (ER) fluid subjected to temperature variations, mechanical and electrical fatigues. As a first step, an arabic gum-based ER fluid is made by choosing 30% of particle weight-concentration. Using the couette type of the electroviscometer, the field-dependent yield shear stress and current density of the ER fluid are measured by changing the operating temperature from −5°C to 85°C. A reciprocating cylinder mechanism is then manufactured to test mechanical endurance of the ER fluid. Under the specific excitation stroke and frequency, the variation of the yield shear stress is investigated with respect to the operating cycle up to one million cycles. In addition, following the construction of test mechanism for electrical endurance of the ER fluid, the yield shear stress and surface roughness of the electrode are evaluated as a function of the number of the electric-field cycle.     

电致流变流体──一种机敏材料

本文回顾了电致流变流体的发展状况，阐述了电致流变效应的影响因素及作用机理，指出了ＥＲ流体的使用前景。     

电流变体智能材料在交变电场下的透光性能研究

电流变体作为智能材料作动器的一种,在外加电场的作用下,其材料性能会发生显著的变化。本文主要研究了二氧化硅／淀粉复合颗粒电流变体在交变电场作用下的透光性能的变化。对不同浓度的流体、不同外加电场强度,不同外加电场频率以及不同电极间距几种情况下电流以变体的透光性均进行了测试。