Bulk FePt/Fe3Pt nanocomposite magnets prepared by spark plasma sintering

TitleBulk FePt/Fe3Pt nanocomposite magnets prepared by spark plasma sintering
Publication TypeJournal Article
Year of Publication2007
AuthorsRong CB, Nandwana V, Poudyal N, Liu JP, Saito T, Wu YQ, Kramer MJ
Journal TitleJournal of Applied Physics
Volume101
Pages09K515
Date PublishedMay
Type of ArticleProceedings Paper
ISBN Number0021-8979
Accession NumberISI:000246567900383
Keywordsanisotropy, co, FEPT, nanoparticles, permanent-magnets, phase, simulation
Abstract

FePt/Fe3Pt bulk nanocomposite magnets have been prepared by the spark plasma sintering of chemically synthesized FePt and Fe3O4 nanoparticles under 100 MPa at 400-600 degrees C. It was found that the phase transition of the FePt compound from the face centered cubic to the L1(0) started at 500 degrees C and was almost completed at 600 degrees C during the sintering. The activated atomic diffusion during the phase transition led to a significant increase in density. The density about 70% of the theoretical value has been obtained. Grain size of the sintered samples remains nanoscale even after a postannealing at 700 degrees C. Pressure rather than temperature was more effective in enhancing intergrain exchange coupling compared to temperature. (c) 2007 American Institute of Physics.

DOI10.1063/1.2710811
Alternate JournalJ. Appl. Phys.