Title :
Exchange coupling and the grain boundary in magnetic nanocomposites
Author :
O´Donnell, K. ; Rao, X.-L. ; Cullen, J.R. ; Coey, J.M.D.
Author_Institution :
Dept. of Phys., Trinity Coll., Dublin, Ireland
fDate :
9/1/1997 12:00:00 AM
Abstract :
The grain boundary phase/material found to be present in two-phase mechanically alloyed nanocomposites of Sm2Fe17N 3/Fe and Nd2Fe14B/Fe was characterized using Mossbauer spectroscopy and magnetization measurements. The fraction of iron in this third component is typically 10-15% in Sm2 Fe17N3/Fe and 4-5% in Nd2Fe14B/Fe nanocomposites. The influence of the grain size of the nanocomposite and the grain boundary material on the susceptibility was studied and the results are discussed in terms of the model of Wang and Mills
Keywords :
Mossbauer effect; boron alloys; composite materials; exchange interactions (electron); ferromagnetic materials; grain boundaries; grain size; iron; iron alloys; magnetic susceptibility; magnetisation; mechanical alloying; nanostructured materials; neodymium alloys; permanent magnets; samarium alloys; Mossbauer spectroscopy; Nd2Fe14B-Fe; Nd2Fe14B/Fe; Sm2Fe17N3-Fe; Sm2Fe17N3/Fe; exchange coupling; grain boundary; grain size; magnetic nanocomposites; magnetization; susceptibility; two-phase mechanically alloyed nanocomposites; Couplings; Grain boundaries; Iron alloys; Magnetic materials; Magnetization; Mechanical variables measurement; Nanocomposites; Neodymium; Samarium alloys; Spectroscopy;
Journal_Title :
Magnetics, IEEE Transactions on
