RESEARCH ON FINE PARTICLE MAGNETIC MATERIALS

Abstract

Ferromagnetic and ferrimagnetic fine particles were prepared by suitably heat treating coprecipitated oxalates of the systems Co-Fe, Ni-Fe and Cu-Fe in a wide range of compositions. Decomposition of the oxalates in H produced fine particle metals or alloys, decomposition in air produced ferrites at temperatures as low as 400 C. Smaller particles were prepared by addition of the oxalates into molten KNO3. Extremely fine particles were prepared by a precipitation process, and grown by a hydrothermal process providing a series of ferrite particles from 25 to several hundred angstroms. Magnetic measurements and physical measurements using xray diffraction, electron diffraction, and electron microscopy techniques were used. The magnetic and structural data were analyzed in terms of the theory of ferromagnetic fine particle. Metal borides of Ni, Fe, and Co were prepared as fine particles using Na borohydride as the precipitating agent. (Author)

Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1961
Accession Number
AD0269523

Entities

People

  • W.j. Schuele

Organizations

  • Franklin Institute

Tags

DTIC Thesaurus Topics

  • Borohydrides
  • Decomposition
  • Diffraction
  • Electron Diffraction
  • Electron Microscopy
  • Electrons
  • Magnetic Materials
  • Materials
  • Measurement
  • Microscopy
  • Particles
  • Precipitation

Fields of Study

  • Materials science

Readers

  • Aerosol Science/Aerosol Physics
  • Materials Science and Engineering.
  • Superconducting Magnet Technology

Technology Areas

  • Microelectronics