Title :
Magnetoresistance in nanostructured Co-Ag prepared by mechanical-alloying
Author :
Coey, J.M.D. ; Fagan, A.J. ; Skomski, R. ; Gregg, J. ; Ounadjela, K. ; Thompson, S.M.
Author_Institution :
Dept. of Pure & Appl. Phys., Trinity Coll., Dublin, Ireland
fDate :
3/1/1994 12:00:00 AM
Abstract :
Fine cobalt and silver powders have been ball-milled to yield a granular solid of composition Co30Ag70 in the form of coarse powder. The material is an intimate mixture of grains of fcc Co in a silver matrix. The cobalt is in the single-domain size range, and samples exhibit coercivity (0.07 T at 296 K) and unusual thermomagnetic effects, including field-induced unidirectional anisotropy. There is a large, isotropic negative magnetoresistance, which exceeds 10% at 4.2 K
Keywords :
cobalt alloys; coercive force; ferromagnetic properties of substances; granular materials; induced anisotropy (magnetic); magnetic anisotropy; magnetoresistance; mechanical alloying; nanostructured materials; powder metallurgy; silver alloys; 296 K; 4.2 K; Co30Ag70; FCC Co grains; ball-milling; coarse powder; coercivity; field-induced unidirectional anisotropy; granular solid; mechanical-alloying; nanostructured Co-Ag; negative magnetoresistance; single-domain size; thermomagnetic effects; Alloying; Cobalt; Electrons; Magnetic materials; Magnetization; Magnetoresistance; Physics; Powders; Silver; Solids;
Journal_Title :
Magnetics, IEEE Transactions on
