Magnetic fluid incorporating fine magnetic powder and method for making the same
AssigneeToyota Jidosha Kabushiki Kaisha
InventorsHirohisa Miura, Hiroshi Satou, Hidenori Katagiri, Toshio Natsume, Hidekazu Azuma
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Abstract
A magnetic fluid having a base liquid and magnetic particles with so small average particle diameter as to be of some hundreds of angstroms dispersed in the base liquid. Such a magnetic fluid is produced by ejecting a molten magnetic metal adiabatically from an expansion nozzle against a bath of a base liquid.
Claims11
A magnetic fluid, comprising a base liquid and metallic magnetic particle with average particle diameter of some hundreds of angstroms dispersed therein, said metallic magnetic particles each being suspended in said base liquid as each being directly generated from a metallic vapor through rapid cooling by adiabiatic expansion of said metallic vapor and thereafter directly introduced into a bath of said base liquid.
A magnetic fluid according to clam 1, wherein said magnetic particles are made of iron.
A method for making magnetic fluid comprising a base liquid and metallic magnetic particles with average particle diameter of some hundred angstrums dispersed therein, comprising the steps of:
- preparing a quantity of high temperature stable vapor of a metal, directing said vapor through an expansion nozzle means for adiabatic expansion cooling thereof enough to condense said vapor into particles of said diameter, and directing an output flow from said nozzle means against a quantity of said base liquid.
Dependencies are inferred from the claim text.