Accession Number:

ADP012207

Title:

Fe/SiO2 Nanocomposite Soft Magnetic Materials

Descriptive Note:

Corporate Author:

INFRAMAT CORP FARMINGTON CT

Report Date:

2001-11-01

Pagination or Media Count:

6.0

Abstract:

In an effort to explore new highly resistive soft magnetic materials, FeSiO2 nanocomposite materials have been synthesized using a wet chemical reaction approach in which the precursor complex was annealed at various temperatures. The crystallographic structure, nanostructure, morphology, and magnetic properties of the synthetic FeSiO2 particles were studied by x-ray diffraction, transmission electron microscopy, and magnetic measurements. The experimental results show that for this approach, the alpha-Fe particles are coated with amorphous silica. The progress of the reaction, the purity of FeSiO2 in the synthetic powder, and the Fe particle size are highly dependent on the annealing temperature. By adjusting the annealing temperature, the particle size can be controlled from approximately 20 nm to 70 nm. For the synthetic nanopowder obtained by H2 reduction at 400 deg C, there exists a superparamagnetic behavior below room temperature while for the nanopowders obtained by reduction at higher temperatures, the ferromagnetic behavior is dominant. Based on these studies, optimum synthesis conditions for FeSiO2 nanocomposites is determined.

Subject Categories:

  • Laminates and Composite Materials
  • Electricity and Magnetism

Distribution Statement:

APPROVED FOR PUBLIC RELEASE