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Abstract

The invention discloses a La(Fe,Si)₁₃-based hydride magnetic refrigeration material comprising multiple interstitial atoms and showing a high-temperature stability and a large magnetic entropy change and the method for preparing the same. By reintroducing interstitial hydrogen atoms into an interstitial master alloy La_1-aR_aFe_13-bSi_bX_c through a hydrogen absorption process, a compound with a chemical formula of La_1-aR_aFe_13-bSi_bX_cH_d and a cubic NaZn₁₃-type structure is prepared, wherein R is one or a combination of more than one rare-earth element, X is one or more C, B and the like or their combinations. A desired amount of hydrogen is obtained through a single hydrogen absorption process by means of controlling the hydrogen pressure, temperature and period in the process of hydrogen absorption. The compound can be stable under normal pressure, at a temperature of room temperature to 350° C., that is, the hydrogen atoms can still exist stably in the interstices. The Curie temperature of the compound can be adjusted continuously with a wide range of 180K to 360K by changing its composition. The magnetic entropy change that is more than 2 folds of that of Gd can be obtained around room temperature, and the magnetic hysteresis loss vanishes. In view of the above, this material is a desired magnetic refrigeration material applied at room temperature.

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First Claim