Development and micro-gap flow evaluation of electro-rheological nano-suspensions

Electro-rheological (ER) nano-suspensions based on titanium dioxide nano-particles with particle diameter on the order of 100 nm were prepared. Micro-gap flow behavior and microstructure were evaluated for the suspensions with a particle volume fraction of 8.8 vol%. For the nano-suspension based on a silicone oil, the ER effect and flow behavior were found to be stable during the sharing time on the order of 10(2)s. The ER response measured at a given strength of the electric field for the nano-suspension based on a chemically modified silicone oil was effectively induced by the electric field, especially with low strengths, and it was larger than that of the nano-suspension based on the silicone oil but slightly lower than that based on a hydrocarbon oil. Furthermore, the relaxation of the ER response after removal of the electric field was somewhat slow for the nano-suspension based on the hydrocarbon oil, whereas it was fairly well for the nano-suspension based on the modified silicone oil.