Electrorheological response of modified silica suspensions

Electrorheological (ER) properties of colloidal suspensions composed of silica particles in different type of oils were investigated under DC electric field. Silica particles were prepared through the sol–gel method by hydrolyze of tetraethylorthosilicate (TEOS). Different silica powders were prepared by adding metallic cations (Co2+or Zr4+) in order to study their effect on the ER behaviour. The powders microstructures were characterized by XRD, FT-IR, TGA and SEM. The suspension with higher ER response was tested in an automotive damper instead of classic hydraulic oil.