La(fe,si)13-based multi-interstitial atom hydride magnetic refrigeration material with high temperature stability and large magnetic entropy change and preparation method thereof

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 La1-aRaFe13-bSibXc through a hydrogen absorption process, a compound with a chemical formula of La1-aRaFe13-bSibXcHd 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.

Dependencies are inferred from the claim text.