Preparation method and application of high-iron-content Fe-based amorphous alloy with near-room-temperature magnetothermal effect
Fe83Mo6Si1B7P2C1 amorphous alloy thin strip was prepared by vacuum arc smelting and single-roll melting belt swing method, which solved the problem of insufficient magnetic entropy change value and refrigeration capacity of Fe-based amorphous alloy, and achieved near-room temperature magnetic refrigeration performance of high-iron content alloys , has excellent magnetic refrigeration performance.
Patent Information
- Application Number
- CN202310805058.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-07-03
- Publication Date
- 2025-01-03
AI Technical Summary
The existing Fe-based amorphous alloys have poor performance in magnetic entropy variation and refrigeration capacity, which limits their commercial applications. The Curie temperature of the Fe-based amorphous alloy with high-iron content decreases with the increase of Fe content, which affects its Magnetic refrigeration performance.
The Fe83Mo6Si1B7P2C1 amorphous alloy thin strip was prepared by vacuum arc smelting and single-roll melting belt swing method. After precision weighing and multiple vacuum arc smelting, amorphous thin strip was heated and sprayed in a single-roll melting belt swing furnace to achieve high-iron Preparation of content alloys.
The prepared Fe83Mo6Si1B7P2C1 amorphous alloy thin strip has a Curie temperature near room temperature (300 K), a large magnetic entropy change value and excellent refrigeration ability, showing great potential as a room temperature magnetic refrigeration material.
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Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of high-iron-content Fe-based amorphous alloys and their application in the field of room-temperature magnetic refrigeration, and relates to a preparation method of a high-iron-content Fe-based amorphous alloy with near-room-temperature magnetocaloric effect and its application. Background Art
[0002] Magnetic refrigeration uses the magnetocaloric effect of materials to achieve refrigeration. The magnetic refrigeration technology based on the magnetocaloric effect has attracted the attention of researchers around the world for its environmental protection, high efficiency and low noise. See Advanced Materials, Vol. 23, pp. 821-842, 2011. In 1976, Brown et al. used metal Gd as a magnetic refrigeration material and found that its Curie temperature was 294 K and the magnetic entropy change value was also large, thus creating a new era of room temperature magnetic refrigeration materials. See Journal of Applied Physics, Vol. 47, pp. 3673-3680, 1976. In 2002, O. Tegus et al. prepared MnFeP with a Curie temperature of 305 K. 0.45 As 0.55 Alloys, see 2002 Nature, Vol. 415, pp. 150-152. They are all crystalline metals or compounds of primary phase transition, usually showing large magnetic entropy change values, but at the same time have large hysteresis and thermal hysteresis and structural instability during magnetic transition, which affects their refrigeration efficiency. Amorphous alloy magnetic refrigeration materials based on secondary phase transition have many advantages such as smaller hysteresis and thermal hysteresis, wider action temperature range and larger refrigeration capacity, as well as better thermal stability, see 2010 Applied Physics Letters, Vol. 96, pp. 182503-182506. In particular, Fe-based amorphous alloys, although the magnetic entropy change value is not large, have excellent thermal conductivity, corrosion resistance and mechanical properties, and the raw material price is low. In addition, Fe-based amorphous alloys can be adjusted to make their Curie temperature close to room temperature by adjusting the composition, so that they can be applied to the field of room temperature magnetic refrigeration, which has a huge market.
[0003] However, the magnetic entropy change value and refrigeration capacity of the Fe amorphous alloys reported near room temperature magnetic refrigeration are not very high, which restricts its commercial application. In order to increase the magnetic entropy change value of Fe-based amorphous alloys, it is necessary to increase their saturation magnetization. The ferromagnetism of Fe-based amorphous alloys is mainly provided by the Fe atoms in the alloy, and the size of the saturation magnetization of the alloy depends to a large extent on the Fe content in the alloy. Therefore, increasing the Fe content in Fe-based amorphous alloys helps to increase its magnetic entropy change value. In addition, it has been found that when the Fe content in the alloy exceeds a certain value, the Curie temperature of some high-iron-content Fe-based amorphous alloy systems decreases with the increase of Fe content, see Development Vol. 16, pp. 2063-2064, IEEE Transactions on Magnetics, Vol. 12, pp. 945-947, 1976, Metallurgical Transactions A, No. 10, pp. 771-781, 1979. Therefore, it is expected that a near-room temperature magnetic refrigeration material with a large magnetic entropy change value will be developed based on a high-iron content Fe-based amorphous alloy. 83 Mo6Si1B7P2C1 amorphous alloy. Summary of the invention
[0004] The present invention aims to provide a high iron content Fe2O3 smelting furnace with near room temperature magnetocaloric effect by combining vacuum arc melting and single roll melting strip spinning method. 83 Preparation method and application of Mo6Si1B7P2C1 amorphous alloy ribbon. The alloy has a Curie temperature close to room temperature (300 K), and has a large magnetic entropy change and refrigeration capacity. This work can inspire scholars and engineers to develop iron-based amorphous alloy materials suitable for room temperature magnetic refrigeration.
[0005] The present invention is achieved through the following process: (1) Using a precision balance, weigh Fe (Alfa Aesar, 99.99% by mass), Mo (Alfa Aesar, 99.99% by mass), Fe3P (Alfa Aesar, 99.95% by mass), Si (Alfa Aesar, 99.95% by mass), B (Alfa Aesar, 99.95% by mass), and graphite (Alfa Aesar, 99.95% by mass) according to the pre-set alloy composition to meet the requirements of Fe 83Mo6Si1B7P2C1 (where the ratio is atomic percentage); (2) Put the weighed raw materials into a vacuum arc furnace, purge the vacuum arc furnace with argon, and then start melting in an argon atmosphere, keep the melting conditions the same, and repeat at least 4 times to ensure that it is sufficiently uniform. The melting conditions are: current 100-150A, each melting time 4-5 minutes, so as to obtain an intermediate alloy ingot. (3) Put the intermediate alloy ingot prepared by vacuum arc melting into a quartz tube with a circular nozzle at the bottom in a single-roll melting belt furnace, and fix it in an induction coil, and control the distance between the quartz tube nozzle and the top surface of the copper roller to be 1-1.5mm. Close the furnace body, use a mechanical pump to pre-evacuate a low vacuum, and then use a molecular pump to evacuate the vacuum in the furnace to below 5x10-3 Pa, and then fill the furnace with high-purity argon as a protective gas. At the same time, a proper amount of high-purity argon is also filled into the injection gas tank so that there is a suitable pressure difference between the injection gas pressure and the pressure in the vacuum chamber. Then turn on the power, use high-frequency induction heating equipment to heat the master alloy to an appropriate temperature, press the spray button, and spray the alloy solution onto a copper wheel with a rotation speed of 50m / s. The solution is rapidly cooled and forms a long amorphous thin strip under the action of linear speed.
[0006] The characteristics of the present invention are: the single-roller melt-spinning method is used as the preparation method, the copper wheel has a fast rotation speed, a high cooling rate, and is easy to form amorphous, and the method is simple and easy to operate, and the cost is low. 83 The Curie temperature of Mo6Si1B7P2C1 amorphous alloy ribbon is 300 K. The magnetic entropy change is 2.74 J·kg near the Curie temperature under an external magnetic field of 5 T. -1 ·K -1 , the cooling capacity is 485.21 J·kg -1 The current high iron content Fe 83 Mo6Si1B7P2C1 amorphous alloy has excellent near-room temperature magnetic refrigeration performance and is a very potential candidate material for room temperature magnetic refrigeration. BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Figure 1 : Diagram of the experimental device of the single-roller melting strip method in Example 1; Figure 2 : Fe obtained in Example 1 83 XRD pattern and DSC curve of Mo6Si1B7P2C1 amorphous alloy ribbon; Figure 3 : Fe obtained in Example 1 83 The variation curve of magnetization intensity of Mo6Si1B7P2C1 amorphous alloy ribbon with temperature under 0.02T external field. The inset is the variation curve of the first-order derivative of magnetization intensity with temperature. Figure 4 : Fe obtained in Example 1 83The curve of magnetic entropy change of Mo6Si1B7P2C1 amorphous alloy ribbon as a function of temperature under different external fields. Implementation
[0008] Use a precision balance to weigh the alloy correctly according to the preset alloy composition to meet the Fe 83 Mo6Si1B7P2C1 (where the ratio is atomic percentage); then put the weighed granular raw material into a vacuum arc furnace, purge the vacuum arc furnace with argon, start smelting in an argon atmosphere, keep the smelting conditions the same, repeat at least 4 times to ensure that it is sufficiently uniform, the smelting conditions are: current 100-150A, each smelting time 4-5 minutes, so as to obtain an intermediate alloy ingot. Then put the intermediate alloy ingot prepared by vacuum arc melting into a quartz tube with a circular nozzle at the bottom of a single-roll melting belt furnace, and fix it in an induction coil, and control the distance between the quartz tube nozzle and the top surface of the copper roller to be 1-1.5mm. Close the furnace body, use a mechanical pump to pre-evacuate a low vacuum, and then use a molecular pump to evacuate the vacuum in the furnace to 5x10 -3 Pa, and then high-purity argon is filled into the furnace as a protective gas. At the same time, an appropriate amount of high-purity argon is also filled into the injection gas tank to make a suitable pressure difference between the injection gas pressure and the pressure in the vacuum chamber. Then turn on the power, use the high-frequency induction heating equipment to heat the master alloy to an appropriate temperature, press the injection button, and spray the alloy solution on the copper wheel with a rotation speed of 50m / s. The solution is rapidly cooled and forms a long amorphous thin strip under the action of the linear speed.
[0009] like Figure 2 As shown in the figure, the XRD analysis results of the obtained ribbon sample show that the sample does not have a sharp crystallization peak, but a broad diffraction peak appears near 2θ=45°, which indicates that the prepared samples are completely amorphous. From the DSC curve, it can be seen that as the temperature increases, the ribbon sample exhibits obvious glass transition, supercooled liquid region, and crystallization reaction, and thus it can be determined that the glass transition temperature Tg of the sample is 636K and the initial crystallization temperature Tx is 660K.
[0010] like Figure 3 As shown in the figure, the curve of the variation of the saturation magnetization intensity of the obtained sample with temperature under an external field of 0.02T shows that the Curie temperature of the sample can be determined to be 300K.
[0011] like Figure 4 As shown in Figure 2, under different external field conditions, the obtained samples have the largest magnetic entropy change near the Curie temperature. When the external magnetic field is 5 T, the maximum magnetic entropy change of the sample is 2.74 J·kg -1 ·K -1 , the cooling capacity is 485.21 J·kg -1 .
Claims
1. A preparation method and application of a high iron content Fe-based amorphous alloy with near-room temperature magnetocaloric effect, characterized in that: The prepared samples can be applied to room temperature magnetic refrigeration materials; the high iron content Fe-based amorphous alloy is prepared by the following process: according to the composition ratio, the high-purity raw materials that have been accurately weighed in advance are subjected to vacuum arc melting to obtain an intermediate alloy ingot, and then under the protection of a high-purity argon atmosphere, a single-roll melt spinning method is used to prepare an amorphous alloy strip sample.
2. The use according to claim 1, characterized in that The purity of the Fe, Mo, Fe3P, Si and B raw materials is not less than 99.5wt%.
3. The use according to claim 1, characterized in that The precise weighing is to calculate the mass percentage of each element according to the composition setting, and use an electronic balance to accurately weigh the required raw materials with an error of no more than 10 -5 .
4. The use according to claim 1, characterized in that The preparation steps of the intermediate alloy ingot are: putting the Fe, Mo, Fe3P, Si and B powder particles in the weighed raw materials into a vacuum arc furnace, washing the vacuum arc furnace with argon gas, and then starting smelting in an argon atmosphere. The smelting conditions are: current 100-150A, each smelting time 4-5 minutes, so as to obtain the intermediate alloy ingot.
5. The use according to claim 1, characterized in that When using the vacuum arc melting method, after completing one melting process, wait for the furnace to cool down and turn the alloy over. Repeat this process at least 4 times while keeping the same melting conditions to ensure that it is sufficiently uniform and the mass loss is controlled within 0.1 wt%.
6. The use according to claim 1, characterized in that The preparation steps of the alloy strip sample are as follows: placing the intermediate alloy ingot prepared by vacuum arc melting into a quartz tube with a circular nozzle at the bottom in a single-roll melting strip spinning furnace, and fixing it in an induction coil, and controlling the distance between the quartz tube nozzle and the top surface of the copper roller to be 1-1.5 mm; closing the furnace body, pre-evacuating a low vacuum with a mechanical pump, and then evacuating the vacuum in the furnace to 5x10 -3 Pa, and then high-purity argon is filled into the furnace as a protective gas. At the same time, an appropriate amount of high-purity argon is also filled into the injection gas tank to make a suitable pressure difference between the injection gas pressure and the pressure in the vacuum chamber; then the power is turned on, and the mother alloy is heated to an appropriate temperature using a high-frequency induction heating device. The injection button is pressed to spray the alloy solution onto the copper wheel at an extremely high speed. The solution is rapidly cooled and forms a long amorphous thin strip under the action of the linear speed.
7. The use according to claim 1, characterized in that The copper wheel speed used in the single-roller melting strip method is 50 m / s, and the induction coil heating time is maintained at 2-5 minutes.
8. The high iron content Fe-based amorphous alloy according to any one of claims 1 to 8, characterized in that: The MT curve of the alloy is measured by an MPMS magnetic measurement system, the test external magnetic field is 0.02T, and the test temperature is 80-400K.
9. The Fe-based amorphous alloy with high iron content according to any one of claims 1 to 8, characterized in that: The MH curve of the alloy is measured by an MPMS XL-7 magnetic measurement system, the test external magnetic field is 1.5-5T, and the test temperature is 213-393K.
10. The Fe-based amorphous alloy with high iron content according to any one of claims 1 to 8, characterized in that: The magnetic entropy change of the alloy is calculated by Maxwell's equation.