| abstract |
An electrically conductive ferrofluid composition and a method of preparing and using the ferrofluid composition in a ferrofluid seal apparatus, and which ferrofluid composition comprises a liquid carrier having a colloidal dispersion of ferromagnetic particles in an amount sufficient to provide magnetic properties to the ferrofluid composition and carbon particles in an amount sufficient to provide electrical conductive properties to the ferrofluid composition, the ferromagnetic and carbon particles stabilized in the ferrofluid composition by a surface active dispersing agent. The electrically conductive ferrofluid composition is usefully employed in a ferrofluid exclusion seal apparatus to provide an electrically conductive seal apparatus particularly useful for computer disk drives and sputtering apparatus in the semiconductive industry. |