Effect of mechanical abrasion in polar-molecular electrorheological fluids
نویسندگان
چکیده
Mechanical abrasion is a phenomenon which commonly occurs during the application of polarmolecular electrorheological (PMER) fluids. We experimentally investigate its effect by milling PMER particles for different times. We find that this effect can significantly reduce electrorheological effects of PMER fluids made of butyrolactone-modified TiO2 particles. This reduction results from the reduced interaction between PMER particles due to the loss of polar molecules on the surface of TiO2 particles. It is further revealed that adding proper amount of suitable polar molecules to the host fluid may compensate for the reduction of yield stress which can be about 100% at high electric fields. PACS. 47.65.Gx Electrorheological fluids – 77.22.Ej Polarization and depolarization – 62.20.fg Shapememory effect; yield stress; superelasticity
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