Patent ID: 8137459

Claim:
A method for producing nanoparticles for magnetic fluids by electron beam evaporation and condensation in a vacuum, said method comprising the steps of: evaporating an initial solid inorganic magnetic material selected from the group comprising metals, alloys or oxides thereof; evaporating a carrier made of a solid liquid-soluble material simultaneously with said evaporation of the initial solid inorganic magnetic material by electron-beam heating, the carrier concentration being in the range of from 99 to 70% in a total mixed vapor of the initial solid inorganic magnetic material and the solid liquid-soluble material; and depositing the mixed vapor on a substrate, the step of depositing the vapor on the substrate including: fixing magnetic nanoparticles of the solid inorganic magnetic material during condensation of the mixed vapor on a cooled substrate by solidifying the solid liquid-soluble material on the substrate; adjusting a nanoparticle size by presetting and maintaining the temperature at a specified value below the melting point of the solid liquid-soluble material during deposition of the mixed vapor; obtaining a condensate of the magnetic nanoparticles having a specified size, fixed in the carrier.