2017 Volume 45 Issue 3 Pages 145-147
In our previous study, it was found that pattern electrodes with fine projections enhanced the electrorheological (ER) effect of particle suspensions whose particle content was low. In addition, the chain structures between electrodes were different between pattern and plate electrodes. In this study, we focused on the behavior of ER fluids under low electric field and measured the voltage when chain structures of poly(ethylene glycol) (PEG) / silicon oil suspensions could be observed with the naked eye. In case of the 10 wt% PEG (38 - 75 μm) particles / oil (50 cSt) suspension between pattern electrodes, the chain structures appeared at 85 V. This value was lower than the sample between plate electrodes (125 V). In addition, the voltage became higher by increasing the viscosity of oil and particle content. Furthermore, decreasing particle size also raised the voltage. When electric field is applied to PEG suspensions, particles aggregate on the negative electrode by electrophoresis. We considered that the higher voltage was required to create PEG chain structures when the effect of electrophoresis became stronger.
