Tunable magnetocaloric effect in Gd-based glassy ribbons
Langue
en
Article de revue
Ce document a été publié dans
Journal of Applied Physics. 2011, vol. 110, n° 5, p. 053920 (7 p.)
American Institute of Physics
Résumé en anglais
The series of glassy ribbons Gd60M30In10 (M = Mn, Co, Ni, Cu) was synthesized by melt-spinning. The change of transition element M in these Gd-based metallic glasses was proven to induce huge variations of the Curie ...Lire la suite >
The series of glassy ribbons Gd60M30In10 (M = Mn, Co, Ni, Cu) was synthesized by melt-spinning. The change of transition element M in these Gd-based metallic glasses was proven to induce huge variations of the Curie temperature TC, magnetic entropy change peak values ΔSm<sup>peak</sup>, and widths at half maximum values of the magnetic entropy change δT. When M is non magnetic (M = Co, Ni, Cu), the samples behave similarly: they display high values of ΔSm<sup>peak</sup> (between -6.6 and -8.2 J/kg K in a magnetic field variation of 4.6 T), average δT values (between 77 and 120 K) and no magnetic hysteresis. On the contrary, when M carries a magnetic moment (M = Mn), some irreversibility appears at low temperature, ΔSm<sup>peak</sup> is lower (only 3.1 J/kg K for μ0H = 4.6 T) and the magnetic transition is very large (δT = 199 K for μ0H = 4.6 T). These features are explained by some antiparallel coupling between Mn atoms randomly located in the metallic glass. This leads to the occurrence of a cluster-glass behavior at low temperature (35 K), following the ferromagnetic transition observed at 180 K when the temperature is decreased. Also, power law fittings of ΔSm<sup>peak</sup> and δT versus μ0H were performed and show that δT is less field dependent than ΔSm<sup>peak</sup>. We could then identify an interesting way of improving the refrigeration capacity of the material at low magnetic field.< Réduire
Mots clés en anglais
Nickel alloys
Curie temperature
Cobalt alloys
Copper alloys
Entropy
Gadolinium alloys
Indium alloys
Magnetic transitions
Magnetocaloric effects
Manganese alloys
Melt spinning
Origine
Importé de halUnités de recherche