Gd(sub 90)Co(sub 2.5)Fe(sub 7.5) Alloy Displaying Enhanced magnetocaloric Properties

Published

July 3, 2015

Author(s)

Virgil Provenzano, Robert D. Shull, G Kletetschka, Paul E. Stutzman

Abstract

Because of its attractive magnetocaloric properties, gadolinium (Gd) metal is currently the refrigerant of choice in the development of near-room temperature magnetic cooling prototypes (refrigerators, heat pumps, and air conditioners). The overwhelming use of gadolinium as a refrigerant in magnetic cooling applications is because it exhibits a large magnetocaloric effect (MCE) peak around room temperature together with negligible magnetic hysteresis and a relatively large refrigeration capacity (RC). Although, research and development carried out during the past fifteen years or so has led to discovery of new metallic-based materials with very promising magnetocaloric properties, with initial results pointing to their potential of being better refrigerants than gadolinium, to date this potential has not materialized. Therefore, gadolinium still remains the benchmark refrigerant for near-room temperature magnetic refrigeration applications. In this paper we report on the discovery of a new gadolinium alloy that displays superior magnetocaloric properties to those of gadolinium. This new alloy was obtained by alloying gadolinium with relatively small amounts of cobalt and iron. In this paper we present a magnetically-derived entropy change, SM, MCE peak computed from magnetic data in addition to a thermally-derived temperature change, TAD, MCE peak from direct thermal measurements for both polycrystalline (bulk) gadolinium and the polycrystalline Gd-Co-Fe alloy. Consequently, direct comparison of their magnetocaloric properties can be made. Both the magnetic data-derived and thermal data-derived MCE data showed MCE peaks for the alloy that are taller and broader than the corresponding MCE peaks for polycrystalline gadolinium. In addition, .............

Citation

Nature Materials

Pub Type

Journals

Keywords

Co-Fe-doped gadolinium, magnetocaloric properties, magnetization, magnetic susceptibility and anisotropy

Citation

Provenzano, V. , Shull, R. , Kletetschka, G. and Stutzman, P. (2015), Gd(sub 90)Co(sub 2.5)Fe(sub 7.5) Alloy Displaying Enhanced magnetocaloric Properties, Nature Materials (Accessed April 18, 2024)