Large magnetocaloric effects and thermal transport properties of La(FeSi) 13 and their hydrides

• Published in: Journal of alloys and compounds Vol. 408; pp. 307 - 312
• Main Authors: Fukamichi, K., Fujita, A., Fujieda, S.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.01.2006
• Subjects: Itinerant-electron metamagnetic (IEM); Magnetocaloric effects (MCEs); Room temperature; Magnetocaloric effects (MCEs); Room temperature; Itinerant-electron metamagnetic (IEM)
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2005.04.022

La(Fe x Si 1− x ) 13 exhibit an itinerant-electron metamagnetic (IEM) transition at relatively low applied magnetic fields just above the Curie temperature T C. Large magnetocaloric effects (MCEs) in terms of the isothermal temperature change Δ S m and the adiabatic temperature change Δ T ad are followed by the IEM transition. The MCEs increase, while T C decreases with increasing Fe concentration. Therefore, T C of these compounds should be controlled up to room temperature from the viewpoint of practical applications. The working temperature as magnetic refrigerants is extended from about 185 to 330 K by adjusting hydrogen concentration. After hydrogen absorption, the MCEs as well as the thermal conductivity of La(Fe x Si 1− x ) 13 and their hydrides exhibit excellent characteristics in the temperature range mentioned above. Consequently, the present compounds are one of the promising candidates for magnetic refrigerants working in a wide temperature range covering room temperature.