Ferromagnetic fe-dy hydrogen storage material and preparation method thereof

Abstract

The invention discloses a ferromagnetic Fe-Dy hydrogen storage material, which is made of Fe and rare earth Dy as raw materials, and the chemical formula is Fe obtained through arc melting and heat treatment. 17 Dy 2 Fe‑Dy hydrogen storage materials with Th 2 Ni 17 Ferromagnetic material with a hexagonal crystal structure, the saturation magnetization is 62~100Am 2 / kg, the Curie temperature is 90~100℃, and the hydrogen storage performance is 0.1~0.2wt.%. Its preparation method includes the following steps: 1) Weigh Fe and Dy according to the chemical formula and melt to prepare Fe 17 Dy 2 alloy; 2) Heat treatment of the prepared alloy to obtain Fe-Dy hydrogen storage material. When used as a hydrogen storage material, it has magnetic phase transition characteristics, and the hydrogen storage capacity is 0.11~0.14 wt.% when it is higher than the Curie temperature, and the hydrogen storage capacity is increased to 0.18~0.2 wt.% at the Curie temperature. %. The hydrogen storage material of the invention has a low Curie temperature and its working temperature is near the Curie temperature.

Description

technical field [0001] The invention belongs to the field of new materials and relates to new energy materials, in particular to a ferromagnetic Fe-Dy hydrogen storage material and a preparation method thereof. Background technique [0002] R-T compounds formed by the combination of rare earth elements (R) and transition metals (T) include T 2 R, T 3 R, T 17 R 2 , T 23 R 6 etc. This type of compound has been extensively studied due to the excellent magnetostrictive, magnetoresistance, and magnetocaloric properties due to the interaction of 3d-4f electron shells. However, in the past, people only paid attention to its magnetic properties, and there were few studies on other properties. Nowadays, with the development of society and the advancement of technology, the requirements for materials are not limited to one aspect. In order to fully exert the performance of various aspects of the material and maximize the utilization rate, it is necessary to explore its performan...

AI Technical Summary

Problems solved by technology

[0004] Prior Art Discovery T 23 R 6 Type compounds have hydrogen storage properties and the magnetic properties have changed accordingly after hydrogen storage, but no effect of Curie temperature on hydrogen storage properties has been found.

At the same time, T 23 R 6 Type compounds have a technical problem of high Curie temperature

Although this problem can be reduced by adding a third element, such as Mn, to lower its Curie temperature, a new technical problem arises that Mn is volatile during the smelting process, making it difficult to control the composition and making single-phase compounds difficult to obtain.

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