CN-119480310-B - Magnetic refrigeration material with wide working temperature range and preparation method and application thereof

Abstract

The invention discloses a magnetic refrigeration material with wide working temperature range, a preparation method and application thereof, wherein the magnetic refrigeration material is a pleated alloy film with non-uniform strain gradient, the pleated alloy film with non-uniform strain gradient is obtained by transferring the alloy film, and has extremely wide working temperature range as a magnetic refrigeration material. The invention utilizes the different expansion coefficients and weak van der Waals interactions between the alloy film and the NaCl substrate to enable the film to present a self-supporting fold morphology on the substrate, and the film with the fold morphology has simple preparation process, and can be conveniently separated from the substrate to retain the fold morphology so as to obtain the fold film. After the non-uniform strain gradient is introduced, the saturation magnetization of the pleated film is remarkably improved in a wide temperature range compared with that of a bulk alloy and a flat film. Meanwhile, the magnetic entropy change result shows that the pleated film has extremely wide working temperature range as a magnetic refrigeration material, and the magnetic refrigeration capacity of the pleated film is far higher than that of a bulk alloy and a flat film.

Inventors

• XU QINGYU
• Ling Yechao
• YU XIAO

Assignees

• 东南大学

Dates

Publication Date

20260512

Application Date

20241108

Claims (7)

1. 1. A magnetic refrigeration material having a wide operating temperature range, wherein the magnetic refrigeration material is a pleated alloy film having a non-uniform strain gradient; The preparation method of the magnetic refrigeration material with the wide working temperature range comprises the following steps: (1) Depositing a layer of alloy film on the NaCl single crystal substrate; (2) Performing in-situ annealing after depositing an alloy film, and then cooling to room temperature; (3) Transferring the film on the NaCl substrate by using a low-temperature adhesive tape to obtain a pleated film with non-uniform strain gradient; The temperature for depositing the metal film on the substrate in the step (1) is 400-450 ℃, the method for depositing the alloy film on the NaCl single crystal substrate is a pulse laser deposition method or a laser auxiliary molecular beam epitaxy method, the annealing temperature in the step (2) is 450-500 ℃, and the annealing time is 0.5 h-1 h.
2. 2. The magnetic refrigerator material of claim 1, wherein the magnetic refrigerator material is a pleated alloy film having a non-uniform strain gradient by transferring the alloy film.
3. 3. The magnetic refrigerator material of claim 1, wherein the alloy film has a thickness of 20 nm-50 a nm a.
4. 4. The magnetic refrigeration material having a wide operating temperature range as set forth in claim 1 wherein said alloy film comprises a multi-element heusler alloy.
5. 5. The magnetic refrigeration material having a wide operating temperature range as set forth in claim 1, wherein said alloy film is a Ni-Mn-Sn alloy film.
6. 6. Use of a magnetic refrigeration material according to claim 1 for the preparation of a magnetic refrigeration material having a wide operating temperature range, at the same time having a small transition hysteresis and a high refrigeration capacity.
7. 7. Use of a magnetic refrigeration material according to claim 1 as a refrigeration medium in refrigeration equipment, electronic equipment heat dissipation, precision instruments, aerospace, medical cold chain and cryogenic storage.

Description

Magnetic refrigeration material with wide working temperature range and preparation method and application thereof Technical Field The invention relates to the technical field of new materials, in particular to a magnetic refrigeration material with a wide working temperature range, and a preparation method and application thereof. Background The pulse laser deposition system uses high-energy high-density pulse laser as an excitation source, the high-energy high-density pulse laser is arranged in the vacuum cavity through the focusing system to erode the surface of the solid target, plasma plumes are excited from the solid target, then the plasma plumes are directionally transported to the surface of a target substrate, then plasma in the plumes is rapidly cooled, and finally the solid target is communicated with the surface of the substrate to form a film. The prepared film has uniform thickness, and the components are highly consistent with the target material components, thereby being beneficial to the preparation of the multi-component compound. Meanwhile, the film plating process is pollution-free and easy to control, and the geometric parameters, the laser parameters, the substrate conditions and the reaction atmosphere can be flexibly adjusted to obtain the high-quality film. Because of the size effect and the constraint of the hard substrate, the phase change of the magnetic refrigeration alloy film with the thickness of less than tens of nanometers is inhibited, and a plurality of magnetic response effects related to the phase change are seriously affected. Notably, by decoupling between the film and the substrate, i.e. a self-supporting alloy film with high degrees of freedom and surface to volume ratio, its functionality can be extended by designing complex strain geometries. Currently, there are two typical problems in the field of magnetic refrigeration (1) a limited operating temperature window and (2) a large transition hysteresis. In the prior art (CN 117127202A), a catalyst which utilizes a strain gradient to induce magnetic enhancement and magnetic field response and a preparation method thereof are disclosed, and an alloy film with a fold morphology of the strain gradient is obtained by binding the alloy film, but the fold film can only be used as a catalyst for hydrogen evolution and oxygen evolution reaction. Disclosure of Invention Aiming at the problems existing in the prior art, the invention provides a magnetic refrigeration material with a wide working temperature range, which has small hysteresis, wide working temperature range and high refrigeration capacity, and effectively solves the bottleneck problem in the current magnetic refrigeration field. The invention also provides a preparation method and application of the magnetic refrigeration material with a wide working temperature range. In order to achieve the above purpose, the magnetic refrigeration material with a wide working temperature range is a pleated alloy film with a non-uniform strain gradient. The magnetic refrigeration material is a pleated alloy film with non-uniform strain gradient obtained by transferring the alloy film, and has extremely wide working temperature range as the magnetic refrigeration material. Wherein the thickness of the alloy film is 20nm-50nm. Wherein the alloy film comprises a multi-element heusler alloy. Preferably, the alloy film is a Ni-Mn-Sn alloy film. The preparation method of the magnetic refrigeration material with the wide working temperature range comprises the following steps: (1) Depositing a layer of alloy film on the NaCl single crystal substrate; (2) Performing in-situ annealing after depositing an alloy film, and then cooling to room temperature; (3) Transferring the film on the NaCl substrate using a low temperature tape can result in a pleated film with a non-uniform strain gradient. Wherein, the temperature of the metal film deposited on the substrate in the step (1) is 400-450 ℃, and the method for depositing the alloy film on the NaCl single crystal substrate is a pulse laser deposition method or a laser assisted molecular beam epitaxy method. Wherein the annealing temperature in the step (2) is 450-500 ℃ and the annealing time is 0.5-1 h. Wherein, the annealing and cooling in the step (2) are required to be performed in a high vacuum environment of the cavity. The magnetic refrigeration material provided by the invention is applied to the preparation of the magnetic refrigeration material with wide working temperature range, small transformation hysteresis and high refrigeration capacity. The magnetic refrigeration material with the wide working temperature range is used as a refrigeration working medium in refrigeration equipment, electronic equipment heat dissipation, precision instruments, aerospace, medical cold chain and low-temperature storage. The present invention relates to a magnetic refrigeration material with wide working temperature range, which is induced b