Magnetocaloric effect in high-energy ball-milled Gd5Si2Ge2 and Gd5Si2Ge2/Fe nanopowders

Evolution of structure and magnetocaloric properties in ball-milled Gd5Si2Ge2 and Gd5Si2Ge2/0.1wt% Fe nanostructured powders were investigated. The high-energy ball-milled powders were composed of very fine grains (70-80nm). Magnetization decreased with milling time due to decrease in the grain size...

Ausführliche Beschreibung

Gespeichert in:

Bibliographische Detailangaben
Veröffentlicht in:	Journal of magnetism and magnetic materials 2008-04, Vol.320 (8), p.1479-1484
Hauptverfasser:	RAIKUMAR, D. M, MANIVEL RAIA, M, GOPALAN, R, CHANDRASEKARAN, V
Format:	Artikel
Sprache:	eng
Schlagworte:	Condensed matter: electronic structure, electrical, magnetic, and optical properties Exact sciences and technology Magnetic properties and materials Magnetically ordered materials: other intrinsic properties Magnetocaloric effect, magnetic cooling Physics
Online-Zugang:	Volltext
Tags:	Tag hinzufügen Keine Tags, Fügen Sie den ersten Tag hinzu!

Beschreibung
Zusammenfassung:	Evolution of structure and magnetocaloric properties in ball-milled Gd5Si2Ge2 and Gd5Si2Ge2/0.1wt% Fe nanostructured powders were investigated. The high-energy ball-milled powders were composed of very fine grains (70-80nm). Magnetization decreased with milling time due to decrease in the grain size and randomization of the magnetic moments at the surface. The magnetic entropy change (DeltaSM) was calculated from the isothermal magnetization curves and a maximum value of 0.45J/kgK was obtained for 32h milled Gd5Si2Ge2 alloy powder for a magnetic field change of 2T while it was still low in Fe-contained alloy powders. The thermo-magnetic measurements revealed that the milled powders display distribution of magnetic transitions, which is desirable for practical magnetic refrigerant to cover a wide temperature span.
ISSN:	0304-8853
DOI:	10.1016/j.jmmm.2007.12.005