INVESTIGADORES
RAMAJO leandro Alfredo
artículos
Título:
Dielectric and magnetic response of Fe3O4/epoxy composites
Autor/es:
LEANDRO ALFREDO RAMAJO; ADRIAN CRISTOBÁL; PABLO MARTÍN BOTTA; JOSÉ MANUEL PORTO LÓPEZ; MARÍA MARTA REBOREDO; MIRIAM SUSANA CASTRO
Revista:
COMPOSITES. PART A, APPLIED SCIENCE AND MANUFACTURING
Editorial:
Elsevier Ltd.
Referencias:
Año: 2009 vol. 40 p. 388 - 393
ISSN:
1359-835X
Resumen:
Magnetic and dielectric properties of Fe3O4/epoxy resin composites were studied as a function of Fe3O4 concentration. The Fe3O4 powder was milled using a planetary ball mill in order to reduce the particle size. B.E.T. area of these particles was determined, and lattice parameters were obtained by X-ray diffraction (XRD). Fe3O4/epoxy composites were prepared mixing the raw materials and pouring them into suitable moulds. Dielectric measurements were performed at different frequencies and temperatures, whereas magnetic properties were assessed at different temperatures. It was found that permittivity was strongly dependent on the filler concentration and frequency. Maxwell-Wagner-Sillars interfacial polarisation, Intermediate Dipolar Polarisation (IDE) and  relaxation process were responsible of the observed response. Magnetic measurements revealed the presence of magnetite nanoparticles in the composites, with a blocking temperature close to 170 K.