Enhanced conductivity of magnetorheological fluids based on silver coated carbonyl particles

摘要

Magnetorheological fluid (MRF) are mostly characterized by a remarkable change in their rheological behavior. However, the poor conductivity limit their potential electrical applications. To enhance the electrical properties of MRF, MRF based on silver-coated carbonyl iron (CI) micro-particles dispersed in silicon oil with oleic acid and addictives are prepared. The electrical properties of MRF were remarkably improved due to the inherent outstanding electrical conductivity of silver. The saturation resistance of the modified MRF was about three order magnitude reduced from 7.7 to 14 KΩ. Moreover, the magnetic response speed was around 7 times faster than that of the un-modified materials. Coating good conductivity material on CI particles offers a more practical new mean to improve the electrical characteristics of MRF.