Title :
Magnetic properties of Co/(CoNi)Fe2O4 nanocomposite magnet powders
Author :
Sugimoto, S. ; Haga, K. ; Kagotani, T. ; Inomata, K.
Author_Institution :
Dept. of Mater. Sci., Tohoku Univ., Sendai, Japan
Abstract :
The microstructure and magnetic properties of a nanocomposite magnet powders composed of magnetically soft and hard phases are investigated by XRD and TEM, and by VSM, respectively. The Co nanoparticles (soft magnetic material) and (CoNi)Fe2O4 (hard magnetic material) nanoparticles are mixed under ultrasonic agitation and their nanocomposite powder is obtained by centrifugation and evaporation of the hexane. The comparison between the demagnetization curves of the nanocomposite with those of the single-phase material indicates that the exchange coupling between two phases has been realized. The hysteresis measurements also revealed a higher remanence of the two phase nanocomposite than that of the single phase (CoNi)Fe2O4.
Keywords :
X-ray diffraction; centrifugal casting; cobalt; cobalt compounds; coercive force; crystal microstructure; demagnetisation; evaporation; exchange interactions (electron); ferromagnetic materials; magnetic hysteresis; magnetic particles; nanocomposites; nickel compounds; permanent magnets; remanence; soft magnetic materials; transmission electron microscopy; Co-(CoNi)Fe2O4; TEM; VSM; XRD; centrifugation; demagnetization; evaporation; hard magnetic material; hard-soft exchange coupling; hexane; hysteresis loops; magnetic properties; microstructure; nanocomposite magnet powders; nanoparticles; remanence; single-phase material; soft magnetic material; two-phase nanocomposite; ultrasonic agitation; Demagnetization; Magnetic hysteresis; Magnetic materials; Magnetic properties; Microstructure; Nanoparticles; Phase measurement; Powders; Soft magnetic materials; X-ray scattering;
Conference_Titel :
Magnetics Conference, 2005. INTERMAG Asia 2005. Digests of the IEEE International
Print_ISBN :
0-7803-9009-1
DOI :
10.1109/INTMAG.2005.1464263