Accession Number : AD0269523

Title :   RESEARCH ON FINE PARTICLE MAGNETIC MATERIALS

Corporate Author : FRANKLIN INST PHILADELPHIA PA LABS FOR RESEARCH AND DEVELOPMENT

Personal Author(s) : SCHUELE,W.J.

Report Date : SEP 1961

Pagination or Media Count : 1

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)

Descriptors :   *BORIDES, *FERRITES, *FERROMAGNETIC MATERIALS, *INTERMETALLIC COMPOUNDS, *IRON COMPOUNDS, *MAGNETIC MATERIALS, *OXALATES, AIR, ATMOSPHERIC PRECIPITATION, BOROHYDRIDES, CHEMICAL PRECIPITATION, COBALT COMPOUNDS, COPPER COMPOUNDS, CRYSTAL LATTICES, CRYSTAL STRUCTURE, ELECTRON DIFFRACTION, ELECTRON MICROSCOPY, HYDROGEN, MAGNETIC PROPERTIES, MAGNETIC PROPERTIES, NICKEL COMPOUNDS, OXIDATION, PARTICLES, PREPARATION, REDUCTION, SODIUM COMPOUNDS, X RAY DIFFRACTION

Distribution Statement : APPROVED FOR PUBLIC RELEASE