A rare earth-based high-entropy amorphous alloy with high magnetocaloric effect and its preparation method

Abstract

The invention discloses a rare earth-based high-entropy amorphous alloy material with high magnetocaloric effect, and its molecular formula is Gd a co b Al c Y d m e , where a, b, c, d, and e represent the atomic percentages of the corresponding elements, and 24.8≤a≤25.4, 24.8≤b≤25.4, 24.8≤c≤25.4, 5≤d≤15, 10≤e≤ 20, a+b+c+d+e=100, wherein M is one of Dy, Er or Ho. On the basis of GdCoAlY high-entropy amorphous, M element is used to replace Y element to obtain a high-entropy amorphous alloy with high magnetocaloric effect. sexual element. Moreover, the patented high-entropy amorphous alloy has a completely amorphous structure without crystallization heat treatment, and the preparation process is simple. It is a high-entropy amorphous alloy with good magnetocaloric properties and good application prospects in the field of magnetic refrigeration technology. alloy.

Description

technical field [0001] The invention relates to a rare earth-based high-entropy amorphous alloy magnetic refrigeration material technology, in particular to a rare-earth-based high-entropy amorphous alloy with large half-peak width and high magnetocaloric effect and a preparation method thereof. Background technique [0002] Since the 21st century, the contradiction between man and nature has become increasingly prominent, and environmental issues have become important issues affecting people's living standards and future development. Global warming has become one of the main threats to the world's environmental security, and the greenhouse gases that cause global warming have gradually become an important consideration for governments to formulate environmental policies. Therefore, there is an urgent need to develop a refrigeration material that is green, safe, high in refrigeration efficiency and does not emit greenhouse gases. Different from the traditional gas mechanica...

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Problems solved by technology

When strict environmental protection requirements made it difficult to continue traditional compression refrigeration, people began to do a lot of exploration on new magnetic refrigeration materials, and prepared a series of magnetic refrigeration materials with giant magnetocaloric effects, including Gd 5 (SixGe1-x) 95 , MnFeGeZn, DyYCo, LaFeCoSi and their hydrides and other series alloys, these alloys show a giant magnetic effect, and a large magnetic entropy change near the Curie temperature, but these materials have a narrow magnetic phase transition temperature range and poor cooling capacity

Chinese patent CN102965562A discloses a magnetic refrigeration material with giant magnetocaloric effect, Mn 2-x Fe x Ge z Zn z , 0.8≤x≤0.9, 0.2≤y≤0.27, 0.001≤z≤0.002, the maximum magnetic entropy change is higher than 26Jkg -1 K -1 However, in order to obtain the crystal structure of its single-crystal phase compound, mechanical ball milling and high-temperature sintering are required. The preparation process is complicated and energy-consuming, which greatly increases the time and energy costs for industrialization, hindering its practical application.

However, the alloy has poor forming ability, and its relative magnetic refrigeration capacity is only 325Jkg -1 , which greatly limits the application of the alloy

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