极板形貌修饰对电流变液/极板界面滑移抑制实验研究

被外电场极化而固化的电流变液容易在极板处产生剪切滑移而降低其力学性能.使用抛光、激光打坑、覆盖尼龙网和光刻腐蚀四种方法对极板形貌进行了修饰，并对电流变液的压缩力学性能进行了测试.研究表明，光滑极板和光刻腐蚀柱阵列极板易产生界面滑移而压缩强度较低，粗糙坑阵列和覆盖尼龙网可抑制界面滑移而压缩强度高.极板形貌增强极板附近局部电场强度，强化了链末端与极板间的作用，迫使链结构屈服位置远离链末端，从而有效抑制了滑移.研究结果对进一步认识电流变液的屈服强度，提高电流变器件的力学性能有重要参考价值. 关键词： 电流变液 滑移 极板形貌修饰 压缩应力

Enhancing compressive strength of electrorheological fluid by patterning the electrode

Slip at the interface of solidified electrorheological (ER) fluid and electrodes is harmful for ER applications. Compression tests using four kinds of electrodes, namely the smooth, hole array patterned by laser pulse, nylon net covered, and acid etched column patterned electrodes, have been done, respectively. Results show that laser patterned and nylon net covered electrodes significantly enhanced the compressive stress of the ER fluid. The enhancement is ascribed to the increase of local electric field near electrodes after patterning, which increased the interfacial strength between ER fluid and electrodes, and effectively suppressed the slip of solidified ER fluid from electrode. The tests of current density during compression and the finite element analysis of the electric field distribution of patterned electrodes supported this slip suppression effect. The results raised a fundamental question of what is the real strength of ER fluids, since the slip of highly solidified ER fluid are usually not considered during various tests. This investigation also shows that patterning electrodes is a good way to improve mechanical performances of ER fluids.