Document Type
Article
Source Publication Title
Applied Physics Letters
Abstract
High density bulk FePt/Fe3Pt nanocomposite magnets have been prepared by high-pressure warm compaction of chemically synthesized FePt and Fe3O4 nanoparticles. It is found that the density increases with the compaction pressure and temperature. Density of the bulk samples up to 95% theoretical value has been obtained while the nanostructured morphology is retained. It is also observed that a high pressure expedites the FePt phase transition from the disordered face-centered-cubic structure to the L10 structure, leading to the phase transition temperature in the compacts one hundred degrees lower than usual. This phase transition in turn facilitates the consolidation of the compacts. Magnetic characterizations showed that interphase exchange coupling is enhanced upon the compaction. Post-annealing of the compacts results in further improved magnetic performance of the compacts owing to interface modification. Energy products up to 16.3 MG Oe of the isotropic bulk nanocomposite magnets have been achieved, which is significantly higher than the theoretical limit for fully dense single-phase FePt magnets.
Disciplines
Physical Sciences and Mathematics | Physics
Publication Date
1-1-2007
Language
English
License
This work is licensed under a Creative Commons Attribution-NonCommercial-Share Alike 4.0 International License.
Recommended Citation
Nandwana, Vikas; Liu, J. Ping; Poudyal, Narayan; Rong, Chuan-Bing; Kozlov, Mikhail E.; Baughman, Ray H.; Ding, Yong; and Wang, Zhong Lin, "Bulk FePt-based nanocomposite magnets with enhanced exchange coupling" (2007). Physics Faculty Publications. 27.
https://mavmatrix.uta.edu/physics_facpubs/27