Dielectric and electrical properties of electrorheological carbon suspensions

Temperature effect of electrorheological fluids based on polyaniline derived carbonaceous nanotubes

“…Among these ER materials, carbonaceous materials were considered to be one of the most promising materials due to their anhydrous character, good ER efficiency, low density, and low electric power consumption [7]. Carbonaceous ER materials could be prepared from various organic sources [17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32]. For example, Kojima et al synthesized a kind of carbonaceous ER material composed of condensed polycyclic aromatic compounds with phenyl group and diphenyldiacetylene oligomers by annealing diphenyldiacetylene at an elevated pressure [20,21].…”

Temperature-dependent electrorheological effect and its description with respect to dielectric spectra

“…This fact can be a consequence of an enhancement of the conductivity and/or polarizability of the particles together with a reduction in the viscosity of silicone oil (Jiang et al, 2015;Kim et al, 2007;Niu et al, 2014;Yin et al, 2011). The dispersed particles commonly used in ER fluids are semiconductors, whose conductivity and polarizability significantly increase with increasing temperature through thermally activated process (Mrlik et al, 2014;Negita et al, 2008). This behaviour stands in opposition to magnetorheological (MR) fluids, which are magnetic analogues of ER fluids.…”

Enhanced Electrorheological Performance of Nb-Doped TiO2 Microspheres Based Suspensions and Their Behavior Characteristics in Low-Frequency Dielectric Spectroscopy

“…Electrorheological (ER) fluids composed of polarizable solid particles dispersed in an insulating medium are suspensions whose viscosity or shear strength can reversibly and quickly change under an applied external electric field. − This phenomenon has attracted much attention from both academic and industrial communities for potential uses in various mechanical devices, such as clutches, valves, and damping devices. − However, until now, there are still several limitations for commercialization of ER fluids because of relatively low polarization force. − To overcome the poor ER effect, many efforts have been made to improve the ER performance, such as doping with rare-earth (RE) ions, − changing the morphology, , and designing complex structure. − Among these efforts, the doping element is a simple and effective method to improve the ER activity. Nevertheless, this method often induces the change of the material composition, crystal structure, intermicrostructure, the size of particles, defects, and charge-carrier state.…”