共查询到19条相似文献,搜索用时 125 毫秒
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智能复合材料结构的主动振动控制 总被引:4,自引:0,他引:4
本文提出应用电流变体(Electro-Rheological Fluids)材料作为复合材料结构振动主动控制的材料,针对含电流变体材料的智能复合材料悬臂梁,进行了振动的主动控制,测试了智能复合材料悬臂梁在外加电场作用下,弹性模量、衰减系数、固有频率等振动特性的变化,同时,针对不同的梁材料,给出了材料变化对梁振动控制的影响. 相似文献
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电流变体特性及电流变体应用器件的进展 总被引:2,自引:0,他引:2
本文详细评述了电流变体(ERF)材料的组成、工作机理及其流变力学性能,提出以Bingham塑性体来近似描述电流变体的流变特性,综述了电流变体在智能材料、汽车离合器、液压阀门等器件中的应用,给出了含电流变体的双层智能复合材料梁单层、双层加电状态对其振动特性的影响,设计了含电流变体的主动控制式减振器,并对其在外加电场作用下的减振性能进行了评价。 相似文献
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介绍了法国METRAVIB公司MAK-04型粘弹谱仪对电流变体的测试,重点阐述了在不同电压及频率下得到的电流变体粘弹性性能随外加电压变化的规律。 相似文献
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电流变体是近年来新兴的一个领域,由于其广阔的应用前景电流变体材料已成为智能材料研究的热点.ER液体的流变性能在外电场作用下可发生类液-固相的转变,并且这种转变是可控、可逆并且瞬间完成的,因此,ER流体己成为目前结构智能化控制及高性能的机电一体化技术的首选材料[1].目前,电流变体未能达到工业设计的要求,是导致电流变技术研究进展缓慢的关键,所以,研制综合高性能电流变体是目前的当务之急. 相似文献
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Herein, the effect of the degree of deacetylation (DD) on the gelation of the chitosan dispersed suspension as an electrorheological (ER) fluid under an electric field is presented. The fluids were prepared by dispersing the chitin and the chitosan particles having various DDs into silicone oil, and they were evaluated under various electric fields. The alignment of chitosan particles in the fluid was also observed using an optical microscope under the electric field. The formed fibrous structure between electrodes are though to continue to the viscosity increase, because an attempt to move one electrode relative to the order would be hindered by the drag of the dangling fibrils. A noteworthy result is that the region of the frequency for gel state of the ER fluids increased in the order of chitosan DD 99.3, 93.4, 73.2, 83.8, and 87.3% under electric fields while the modulus of the fluids increased in the reverse order. This order was well-matched with the result of dielectric constants and yield stresses of ER fluids. The study of influence of DD on the gelation of the chitosan dispersed suspension under an electric field shows the relevance of the chemical composition of the heteropolysaccharide (chitin-chitosan copolymer) to the rheological and electric properties of ER suspensions. 相似文献
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Ling ZHENG Yinong LIState Key Laboratory of Mechanical Transmission Chongqing University Chongqing ChinaAssoc. Prof. Ph.D. 《材料科学技术学报》2005,21(1):83-86
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. 相似文献
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Ying Dan Liu 《Materials Letters》2010,64(2):154-297
Polyaniline (PANI) fibers as well as silica nanoparticle decorated PANI (silica-PANI) fibers were successfully synthesized as a dispersed phase of an electrorheological (ER) fluid. The fibers obtained through interfacial polymerization were about 300-400 nm in diameter and 2-5 μm long. Then the fibers were redispersed in ethanol containing tetraethyl orthosilicate (TEOS), and silica nanoparticles were formed on the surface of the fibers through a modified Stöber method. The ER characteristics of the ER fluids based on pure PANI fibers and silica-PANI fibers were examined under various electric field strengths using a rotational rheometer, demonstrating slight different flow curves for the silica-based ER fluid. 相似文献
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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. 相似文献
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Electroactive response of mesoporous silica and its nanocomposites with conducting polymers 总被引:1,自引:0,他引:1
Electroactive response of suspensions of mesoporous silica and its nanocomposites with conducting polyaniline and copolyaniline inside its channels were examined under an electric field, mainly focusing on their rheological characteristics. Initially these conducting polymer/mesoporous silica nanocomposites were synthesized and their physical properties were studied by scanning electron microscopy, transmission electron microscopy and N2-adsorption isotherm. Then, mesoporous silica and its nanocomposites were dispersed in silicone oil as an electrorheological (ER) material. Typical ER behaviors of shear stress and shear viscosity curves as a function of electric field and shear rate were observed. Without an electric field, the suspensions behaved almost like a Newtonian fluid. However, under an electric field, their shear stresses increased with shear rate, demonstrating a yield stress. Compared with mesoporous silica and polyaniline, polyaniline/mesoporous silica-based ER fluid showed enhanced ER performance due to the anisotropic characteristics. In addition, it was found that a suggested shear stress model (Cho–Choi–Jhon model) well described the flow curves. 相似文献
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对甲苯磺酸掺杂聚邻甲苯胺的合成及电流变性能 总被引:1,自引:0,他引:1
以对甲苯磺酸(TSA)作为掺杂剂和乳化剂,乳液聚合合成了对甲苯磺酸掺杂聚邻甲苯胺(TSA-POT)。采用红外光谱、热重分析和扫描电镜对聚合物的结构、热稳定性及形貌进行了表征。制备了TSA-POT/硅油(SO)无水型电流变流体(ER流体),测试了其电流变性能,考察了电场强度、反掺杂条件、粒子浓度等因素对TSA-POT/SO体系电流变性能的影响。结果表明,由于强极性的磺酸基团与聚邻甲苯胺的主链相连,极大地改善了聚合物粒子的极化性能,因此TSA-POT/SO体系的电流变性能显著改善。结果同时表明,低浓度的TSA-POT/SO体系的屈服应力与电场强度具有二次线性关系。 相似文献