Gadolinium-erbium aluminum soft magnetic materials and their preparation methods

Abstract

This invention discloses a gadolinium-erbium aluminum soft magnetic material with the chemical formula Gd 3‑x Er x Al2, wherein the rare earth elements are gadolinium (Gd) and erbium (Er), x = 0–0.5. This invention also discloses a method for preparing gadolinium-erbium aluminum soft magnetic material. This invention can obtain soft magnetic materials with adjustable Curie temperature, moderate magnetic entropy change under low magnetic fields, and high cooling capacity.

Description

Technical Field

[0001] This invention relates to a soft magnetic material in magnetic materials, specifically to a gadolinium-erbium aluminum soft magnetic material and its preparation method. Background Technology

[0002] The magnetocaloric effect is the physical basis of magnetic refrigeration technology, manifested as the heat absorption and release phenomena generated by magnetic materials when an external magnetic field changes. Its main characteristic parameters include isothermal magnetic entropy change and adiabatic temperature change. In existing magnetic refrigeration systems, the cooling capacity provided by the magnetic refrigeration material is transported to the target through a heat transfer fluid. Therefore, improving the overall performance of magnetic refrigeration materials has become a research hotspot.

[0003] Based on the continuous entropy change at the phase transition point, magnetic refrigeration materials can be divided into first-order phase transition materials and second-order phase transition materials. First-order phase transition materials (such as La(Fe,Si)13 hydride, Mn-Fe-P compounds, and Gd-Si-Ge alloys) can achieve (-ΔSm)max of 29, 23, and 15 J / (kg·K) under a magnetic field of 0–2T, respectively, due to the structural phase transition accompanying their magnetic phase transition. However, these materials suffer from significant thermal / magnetic hysteresis effects, poor mechanical properties, and narrow operating temperature ranges, which limit their practical applications.

[0004] In contrast, the typical second-order phase change material Gd exhibits a maximum (-ΔSm) of approximately 5.4 J / (kg·K) in a 0–2 T magnetic field, a thermal temperature change of 5.5 K, and its excellent processing properties allow it to be fabricated into uniform spherical particles, significantly improving the performance of refrigeration systems and making it the mainstream material for room-temperature magnetic refrigeration. However, Gd's Curie temperature (T) is limited. C Its application range is limited by being fixed around 293K.

[0005] Vacuum quenching is a comprehensive technology combining vacuum technology and heat treatment, referring to the entire quenching process being carried out under vacuum conditions. Vacuum quenching has high thermal efficiency, enabling steady heating and rapid cooling, and can achieve oxidation-free, decarburization-free, and carburization-free processes. It can also refine grains and improve the hardness, strength, and corrosion resistance of metallic materials.

[0006] Currently, common pipe sealing methods have poor sealing efficiency, and most can only process one set of pipes at a time, resulting in low processing efficiency that cannot meet the needs of modern processing and production. At the same time, the sealing quality of the pipes is not high, which reduces the quality of the product.

[0007] Overcoming the above-mentioned technical problems in the existing technology is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0008] The purpose of this invention is to provide a gadolinium-erbium aluminum soft magnetic material and its preparation method, which can obtain a soft magnetic material with adjustable Curie temperature, moderate magnetic entropy change under low magnetic field and high cooling capacity.

[0009] To achieve the above objectives, the technical solution used in this invention is: Gadolinium-erbium aluminum soft magnetic material, chemical formula Gd 3-x Er x Al2, in which the rare earth elements are gadolinium (Gd) and erbium (Er), x=0-0.5.

[0010] Furthermore, for x = 0, 0.1, 0.2, 0.3, 0.4 or 0.5, the gadolinium-erbium aluminum soft magnetic material is a granular magnetic working fluid.

[0011] Furthermore, the particle size range is 0.08mm-3mm.

[0012] Furthermore, the particulate magnetic working material is in the form of sheets, granules, or strips.

[0013] Furthermore, the thickness of the sheet-like or strip-shaped magnetic working material ranges from 0.08 mm to 5 mm.

[0014] Furthermore, the Curie temperature range of the gadolinium-erbium aluminum soft magnetic material is 131K-279K.

[0015] Furthermore, as the Er content increases, the lattice constant and unit cell volume exhibit a monotonically decreasing trend.

[0016] Methods for preparing gadolinium-erbium aluminum soft magnetic materials include: According to the chemical formula Gd 3-x Er x Al2 is used as raw material, x=0-0.5. After being crushed, it is placed in a glass tube, sealed, and evacuated to a negative value. Then, the tube is sealed under inert gas protection. After the glass tube is welded, the glass tube containing gadolinium-erbium aluminum soft magnetic material is placed in a heat treatment furnace for high-temperature heat treatment; the temperature range of the high-temperature heat treatment of gadolinium-erbium aluminum soft magnetic material is 800℃-1150℃, and the heat treatment time is 24h-168h. After quenching, the gadolinium-erbium aluminum soft magnetic material is removed from the glass tube and dried. Then it is crushed in a crusher to obtain granular magnetic working material.

[0017] Preferably, the erbium content increases in the following proportions: 0.1, 0.2, 0.3, 0.4, and 0.5, while the gadolinium content decreases accordingly starting from 3. The raw materials are then placed in a vacuum melting furnace to prepare gadolinium-erbium aluminum soft magnetic materials.

[0018] Preferably, when the high-temperature heat treatment reaches the set time, the quartz glass tube is removed and quickly immersed in cold water for quenching. Ice cubes are added to the water before quenching to maintain a low temperature.

[0019] The technical effects of this invention include: In this invention, the gadolinium-erbium aluminum soft magnetic material is obtained by using a heat treatment process to obtain an alloy with refined grains.

[0020] This invention addresses the shortcomings of existing traditional single-stage phase change magnetic refrigeration materials, which suffer from significant thermal / magnetic hysteresis, poor mechanical properties, and narrow operating temperature ranges, hindering their practical application. This invention solves these technical problems by employing a heat treatment process to obtain a grain-refined alloy, namely, the gadolinium-erbium aluminum soft magnetic material working fluid.

[0021] Gadolinium-erbium aluminum soft magnetic materials exhibit a gradual decrease in lattice constant and unit cell volume with increasing Er content. The magnetic workings of gadolinium-erbium aluminum soft magnetic materials at their respective Curie temperatures (Ti) show this effect. C Ferromagnetic-paramagnetic second-order phase transitions occur near the 0 and 131 K (x=0.5) as the Er content increases, indicating that wide-temperature-range refrigeration can be achieved through stepwise cooling technology.

[0022] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0023] Figure 1 This is a powder X-ray diffraction pattern of the gadolinium-erbium aluminum soft magnetic material in this invention; Figure 2 This is a schematic diagram of the crystal structure of the gadolinium-erbium aluminum soft magnetic material in this invention; Figure 3 This is the MT (basic magnetization curve) curve of the gadolinium-erbium aluminum soft magnetic material in this invention; Figure 4 This is a graph showing the relationship between the Curie temperature (TC) and Er content of the gadolinium-erbium aluminum soft magnetic material (x=0-0.5) in this invention. Figure 5 This is a schematic diagram of the (-ΔSm)-T curve of the gadolinium-erbium aluminum soft magnetic material (x = 0-0.5) alloy in the present invention within the magnetic field variation range of 0-2 T; Figure 6 This is a graph showing the magnetization (M) and demagnetization (D) curves of the gadolinium-erbium aluminum soft magnetic material alloy in this invention; Figure 7 This is a flowchart of the preparation method of gadolinium-erbium aluminum soft magnetic material in this invention; Figure 8 This is a schematic diagram of the MH curve of the gadolinium-erbium aluminum soft magnetic material (x = 0) in Embodiment 1 of the present invention; Figure 9This is a schematic diagram of the MH curve of the gadolinium-erbium aluminum soft magnetic material (x = 0.1) in Embodiment 2 of the present invention; Figure 10 This is a schematic diagram of the MH curve of the gadolinium-erbium aluminum soft magnetic material (x = 0.2) in Embodiment 3 of the present invention; Figure 11 This is a schematic diagram of the MH curve of the gadolinium-erbium aluminum soft magnetic material (x = 0.3) in Embodiment 4 of the present invention; Figure 12 This is a schematic diagram of the MH curve of the gadolinium-erbium aluminum soft magnetic material (x = 0.4) in Embodiment 5 of the present invention; Figure 13 This is a schematic diagram of the MH curve of the gadolinium-erbium aluminum soft magnetic material (x = 0.5) in Embodiment 6 of the present invention. Detailed Implementation

[0024] The following description fully illustrates specific embodiments of the invention to enable those skilled in the art to practice and reproduce them.

[0025] Gadolinium-erbium aluminum soft magnetic material, with the chemical formula Gd 3-x Er x Al2, in which the rare earth elements are gadolinium (Gd) and erbium (Er), x = 0, 0.1, 0.2, 0.3, 0.4, 0.5.

[0026] like Figure 1 The image shown is a powder X-ray diffraction pattern of the gadolinium-erbium aluminum soft magnetic material of this invention; as shown... Figure 2 The diagram shown is a schematic representation of the crystal structure of the gadolinium-erbium aluminum soft magnetic material in this invention; as shown... Figure 3 The figure shown is the MT (fundamental magnetization curve) curve of the gadolinium-erbium aluminum soft magnetic material in this invention; as shown... Figure 4 The figure shows the Curie temperature (T) of the gadolinium-erbium aluminum soft magnetic material (x=0-0.5) in this invention. C A graph showing the relationship between Er content and its variation; for example... Figure 5 The figure shown is a schematic diagram of the (-ΔSm)-T curve of the gadolinium-erbium aluminum soft magnetic material (x=0-0.5) alloy in this invention within a magnetic field range of 0-2T; as shown... Figure 6 The figure shown is a magnetization (M) and demagnetization (D) curve of the gadolinium-erbium aluminum soft magnetic material alloy in this invention.

[0027] After the magnetic working material is prepared, its performance is tested. The preparation method of the provided gadolinium-erbium aluminum soft magnetic material adopts a heat treatment accelerated cooling method to maintain the excellent magnetic properties of the formed gadolinium-erbium aluminum soft magnetic material. The experiment found that the alloy TC (Curie temperature) is directly proportional to its de Gennes factor (de Gennes factor is a physical parameter describing the magnetic behavior of rare earth ions). When x increases from 0 to 0.5, TC decreases linearly from 279 K to 131 K.

[0028] Magnetic property tests show that the alloys undergo a second-order magnetic phase transition near their respective TC values ​​and exhibit low hysteresis loss (-ΔSm). max It remains stable within the range of 2.2-2.5 J / (kg·K).

[0029] Of particular note is that under a magnetic field of 0-2 T, Gd 2.8 Er 0.2 Al2 and Gd 2.7 Er 0.3 Al2 alloys exhibit a high RC (cooling capacity) of 112 J / kg. Based on their excellent MCE (magnetocaloric effect) and good controllability over a wide temperature range of 131-279 K, they meet the requirements for use in magnetic refrigerators.

[0030] This invention prepares raw materials according to the chemical formula (Gd,Er)3Al2, replaces gadolinium with erbium, increases the erbium content in a certain proportion, and decreases the gadolinium content from 3. The raw materials are placed in a vacuum melting furnace to prepare gadolinium-erbium aluminum soft magnetic materials, and sample preparation experiments are carried out.

[0031] like Figure 7 The diagram shown is a flowchart of the preparation method of gadolinium-erbium aluminum soft magnetic material in this invention.

[0032] The preparation method of gadolinium-erbium aluminum soft magnetic material includes: batching according to chemical formula, crushing into small pieces, sealing in tubes using a hydrogen-oxygen welding machine, high-temperature heat treatment, and mechanical crushing into magnetic working fluid. The specific steps are as follows: Step 1: Based on the chemical formula Gd 3-x Er x Al2 ingredients; According to the chemical formula Gd 3-x Er x Al2 was used as raw material, x=0-0.5, and the raw material was placed in a high-frequency vacuum melting furnace to prepare gadolinium-erbium aluminum soft magnetic material. Sample preparation experiments were also conducted.

[0033] Step 2: After the prepared gadolinium-erbium aluminum soft magnetic material is broken, it is placed in a glass tube, sealed, and evacuated to a negative value. Then, the tube is sealed under inert gas protection. The prepared gadolinium-erbium aluminum soft magnetic material is broken into small pieces and placed in multiple glass tubes (high-temperature resistant quartz glass tubes). The glass tubes are then plugged and installed sequentially on a multi-station hydrogen-oxygen water welding machine. The tubes are sealed with a welding torch and evacuated to a negative value. Then, inert gas argon is introduced, and the tubes are simultaneously welded and sealed under the protection of the inert gas.

[0034] Step 3: After welding is completed, the glass tube containing the gadolinium-erbium aluminum soft magnetic material is placed in a heat treatment furnace for high-temperature heat treatment; The quartz glass tubes are removed and placed on a cooling rack to cool. After the quartz glass tubes have cooled, all the quartz glass tubes containing gadolinium-erbium aluminum soft magnetic material are placed in a heat treatment furnace for high-temperature heat treatment, and then quenched in cold water. The temperature range for high-temperature heat treatment of gadolinium-erbium aluminum soft magnetic material is 800℃-1150℃, and the heat treatment time is 24h-168h.

[0035] When the high-temperature heat treatment reaches the set time, the quartz glass tube is removed and quickly immersed in cold water for quenching. Before quenching, a small amount of ice is added to the water to maintain a low temperature.

[0036] Step 4: After quenching, the gadolinium-erbium aluminum soft magnetic material in the glass tube is taken out and dried. Then all the materials are put into a crusher for crushing to obtain granular magnetic working material.

[0037] The particle size range is 0.08mm-3mm. The granular magnetic working material is in the form of sheets, granules, or strips, and the thickness of the sheet or strip magnetic working material ranges from 0.08mm-5mm.

[0038] Example 1 like Figure 8 The figure shown is a schematic diagram of the MH curve of the gadolinium-erbium aluminum soft magnetic material (x = 0) in Embodiment 1 of the present invention.

[0039] Step 1: Prepare the ingredients according to the chemical formula Gd3Al2; This invention is based on the chemical formula Gd 3-x Er x Al2, x=0, was prepared according to the chemical formula Gd3Al2, and the raw materials were placed in a high-frequency vacuum melting furnace to prepare gadolinium-erbium aluminum soft magnetic materials. Sample preparation experiments were also conducted.

[0040] Step 2: After the prepared gadolinium-erbium aluminum soft magnetic material is broken, it is placed in a glass tube, sealed, and evacuated to a negative value. Then, the tube is sealed under inert gas protection. The prepared gadolinium-erbium aluminum soft magnetic material is broken into small pieces with a diameter of 10mm and placed in multiple glass tubes (high-temperature resistant quartz glass tubes). The glass caps are then plugged, and the high-temperature resistant glass tubes are sequentially installed on a multi-station hydrogen-oxygen water welding machine. The tubes are sealed using a welding torch and evacuated to a negative value. Then, inert gas argon is introduced, and the tubes are simultaneously welded and sealed under the protection of the inert gas.

[0041] Step 3: After welding is completed, the glass tube containing the gadolinium-erbium aluminum soft magnetic material is placed in a heat treatment furnace for high-temperature heat treatment; The quartz glass tubes are removed and placed on a cooling rack to cool. After the quartz glass tubes have cooled, all the quartz glass tubes containing gadolinium-erbium aluminum soft magnetic material are placed in a heat treatment furnace for high-temperature heat treatment, and then quenched in cold water. The temperature range for high-temperature heat treatment of gadolinium-erbium aluminum soft magnetic material is 800℃-1150℃, and the heat treatment time is 24h-168h.

[0042] When the high-temperature heat treatment reaches the set time, the quartz glass tube is removed and quickly immersed in cold water for quenching. Before quenching, a small amount of ice is added to the water to maintain a low temperature.

[0043] Step 4: After quenching, the gadolinium-erbium aluminum soft magnetic material in the glass tube is taken out and dried. Then all the materials are put into a crusher for crushing to obtain granular magnetic working material.

[0044] The particle size range is 0.08mm-3mm. The granular magnetic working material is in the form of sheets, granules, or strips, and the thickness of the sheet or strip magnetic working material ranges from 0.08mm-5mm.

[0045] Example 2 like Figure 9 The figure shown is a schematic diagram of the MH curve of the gadolinium-erbium aluminum soft magnetic material (x = 0.1) in Embodiment 2 of the present invention.

[0046] In the second specific implementation, according to Gd 2.9 Er 0.1 Al2 was used to prepare raw materials using chemical formulas, and the preparation and experiments were carried out.

[0047] The specific steps are as follows: 1. Based on the chemical formula (Gd, Er)3Al2, the raw materials were prepared with x=0.1. The raw materials were placed in a high-frequency vacuum melting furnace to prepare gadolinium-erbium aluminum soft magnetic materials, and sample preparation experiments were carried out.

[0048] 2. The prepared gadolinium-erbium aluminum soft magnetic material is broken into small pieces with a diameter of 10mm and placed in multiple quartz glass tubes (high temperature resistant glass tubes). The glass tubes are then plugged and installed sequentially on a multi-station hydrogen-oxygen water welding machine. The vacuum is evacuated to a negative value, and then inert gas argon is introduced. Under the protection of inert gas, the tubes are welded and sealed using a welding torch.

[0049] 3. After welding, remove the quartz glass tube and place it on a cooling rack to cool. After the quartz glass tube has cooled, put all the quartz glass tubes containing gadolinium-erbium aluminum soft magnetic material into a heat treatment furnace for high-temperature heat treatment. The temperature range of the high-temperature heat treatment of gadolinium-erbium aluminum soft magnetic material is 800℃-1150℃, and the heat treatment time is 24h-168h.

[0050] 4. When the high-temperature heat treatment reaches the set time, remove the quartz glass tube and quickly immerse it in cold water for quenching. Before quenching, add a small amount of ice to the water to maintain a low temperature.

[0051] 5. After quenching, the gadolinium-erbium aluminum soft magnetic material in the glass tube is removed and dried. Then, all the materials are put into a crusher for crushing to obtain granular magnetic working material.

[0052] Example 3 like Figure 10 The figure shown is a schematic diagram of the MH curve of the gadolinium-erbium aluminum soft magnetic material (x = 0.2) in Embodiment 2 of the present invention.

[0053] In the third specific implementation, according to Gd 2.8 Er 0.2 Al2 was used to prepare the raw materials using chemical formulas, and the preparation and experiments were carried out. The specific steps are as follows: 1. According to Gd 2.8 Er 0.2 Al2 was used to prepare raw materials with chemical formula, x=0.2, and the raw materials were placed in a high-frequency vacuum melting furnace to prepare gadolinium-erbium aluminum soft magnetic materials. Sample preparation experiments were also conducted.

[0054] 2. The prepared gadolinium-erbium aluminum soft magnetic material is broken into small pieces with a diameter of 10mm and placed in multiple high-temperature resistant glass tubes. The glass tubes are then plugged and installed sequentially on a multi-station hydrogen-oxygen water welding machine. The vacuum is evacuated to a negative value, and then inert gas argon is introduced. Under the protection of inert gas, the tubes are welded and sealed using a welding torch.

[0055] 3. After welding, remove the quartz glass tube and place it on a cooling rack to cool. After the quartz glass tube has cooled, put all the quartz glass tubes containing gadolinium-erbium aluminum soft magnetic material into a heat treatment furnace for high-temperature heat treatment. The temperature range for high-temperature heat treatment of gadolinium-erbium aluminum soft magnetic material is 800℃-1150℃, and the heat treatment time is 24h-168h.

[0056] 4. When the high-temperature heat treatment reaches the set time, remove the quartz glass tube and quickly immerse it in cold water for quenching. Before quenching, add a small amount of ice to the water to maintain a low temperature.

[0057] 5. After quenching, the gadolinium-erbium aluminum soft magnetic material in the glass tube is removed and dried. Then, all the materials are put into a crusher for crushing to obtain granular magnetic working material.

[0058] Example 4 like Figure 11 The figure shown is a schematic diagram of the MH curve for x = 0.3 in the gadolinium-erbium aluminum soft magnetic material in Embodiment 4 of the present invention.

[0059] In the fourth specific implementation, according to Gd 2.7 Er 0.3 Al2 was used to prepare the raw materials using chemical formulas, and the preparation and experiments were carried out. The specific steps are as follows: 1. According to Gd 2.7 Er 0.3 Al2 was used to prepare raw materials with chemical formula, x=0.3, and the raw materials were placed in a high-frequency vacuum melting furnace to prepare gadolinium-erbium aluminum soft magnetic materials. Sample preparation experiments were also conducted.

[0060] 2. The prepared gadolinium-erbium aluminum soft magnetic material is broken into small pieces with a diameter of 10mm and placed in multiple high-temperature resistant glass tubes. The glass tubes are then plugged and installed sequentially on a multi-station hydrogen-oxygen water welding machine. The vacuum is evacuated to a negative value, and then inert gas argon is introduced. Under the protection of inert gas, the tubes are sealed and welded using a welding torch.

[0061] 3. After welding, remove the quartz glass tube and place it on a cooling rack to cool. After the quartz glass tube has cooled, put all the quartz glass tubes containing gadolinium-erbium aluminum soft magnetic material into a heat treatment furnace for high-temperature heat treatment. The temperature range for high-temperature heat treatment of gadolinium-erbium aluminum soft magnetic material is 800℃-1150℃, and the heat treatment time is 24h-168h.

[0062] 4. When the high-temperature heat treatment reaches the set time, remove the quartz glass tube and quickly immerse it in cold water for quenching. Before quenching, add a small amount of ice to the water to maintain a low temperature.

[0063] 5. After quenching, the gadolinium-erbium aluminum soft magnetic material in the glass tube is removed and dried. Then, all the materials are put into a crusher for crushing to obtain granular magnetic working material.

[0064] Example 5 like Figure 12 The figure shown is a schematic diagram of the MH curve for x = 0.4 in the gadolinium-erbium aluminum soft magnetic material in Embodiment 5 of the present invention.

[0065] In the fifth specific implementation, according to Gd 2.6 Er 0.4 Al2 was used to prepare the raw materials using chemical formulas, and the preparation and experiments were carried out. The specific steps are as follows: 1. According to Gd 2.6 Er 0.4 Al2 was used to prepare raw materials with chemical formula, x=0.4, and the raw materials were placed in a high-frequency vacuum melting furnace to prepare gadolinium-erbium aluminum soft magnetic materials. Sample preparation experiments were also conducted.

[0066] 2. The prepared gadolinium-erbium aluminum soft magnetic material is broken into small pieces with a diameter of 10mm and placed in multiple high-temperature resistant glass tubes. The glass tubes are then plugged and installed sequentially on a multi-station hydrogen-oxygen water welding machine. The vacuum is evacuated to a negative value, and then inert gas argon is introduced. Under the protection of inert gas, the tubes are sealed and welded using a welding torch.

[0067] 3. After welding, remove the quartz glass tube and place it on a cooling rack to cool. After the quartz glass tube has cooled, put all the quartz glass tubes containing gadolinium-erbium aluminum soft magnetic material into a heat treatment furnace for high-temperature heat treatment. The temperature range for high-temperature heat treatment of gadolinium-erbium aluminum soft magnetic material is 800℃-1150℃, and the heat treatment time is 24h-168h.

[0068] 4. When the high-temperature heat treatment reaches the set time, remove the quartz glass tube and quickly immerse it in cold water for quenching. Before quenching, add a small amount of ice to the water to maintain a low temperature.

[0069] 5. After quenching, the gadolinium-erbium aluminum soft magnetic material in the glass tube is removed and dried. Then, all the materials are put into a crusher for crushing to obtain granular magnetic working material.

[0070] Example 6 like Figure 13 The figure shown is a schematic diagram of the MH curve for x = 0.5 in the gadolinium-erbium aluminum soft magnetic material in Embodiment 6 of the present invention.

[0071] In the sixth specific implementation, according to Gd 2.5 Er 0.5 Al2 was used to prepare the raw materials using chemical formulas, and the preparation and experiments were carried out. The specific steps are as follows: 1. According to Gd 2.5 Er 0.5 Al2 was used to prepare raw materials with chemical formula, x=0.5, and the raw materials were placed in a high-frequency vacuum melting furnace to prepare gadolinium-erbium aluminum soft magnetic materials. Sample preparation experiments were also conducted.

[0072] 2. The prepared gadolinium-erbium aluminum soft magnetic material is broken into small pieces with a diameter of 10mm and placed in multiple high-temperature resistant glass tubes. The glass tubes are then plugged and installed sequentially on a multi-station hydrogen-oxygen water welding machine. The tubes are sealed with a welding torch and evacuated to a negative value. Then, inert gas argon is introduced, and simultaneous welding is carried out under the protection of inert gas.

[0073] 3. After welding, remove the quartz glass tube and place it on a cooling rack to cool. After the quartz glass tube has cooled, put all the quartz glass tubes containing gadolinium-erbium aluminum soft magnetic material into a heat treatment furnace for high-temperature heat treatment. The temperature range for high-temperature heat treatment of gadolinium-erbium aluminum soft magnetic material is 800℃-1150℃, and the heat treatment time is 24h-168h.

[0074] 4. When the high-temperature heat treatment reaches the set time, remove the quartz glass tube and quickly immerse it in cold water for quenching. Before quenching, add a small amount of ice to the water to maintain a low temperature.

[0075] 5. After quenching, the gadolinium-erbium aluminum soft magnetic material in the glass tube is removed and dried. Then, all the materials are put into a crusher for crushing to obtain granular magnetic working material.

[0076] The terminology used in this invention is descriptive and exemplary, not restrictive. Because this invention can be embodied in many forms without departing from the spirit or essence of the invention, it should be understood that the above embodiments are not limited to any of the foregoing details, but should be interpreted broadly within the spirit and scope defined by the appended claims. Therefore, all variations and modifications falling within the scope of the claims or their equivalents should be covered by the appended claims.

Claims

1. A gadolinium-erbium aluminum soft magnetic material, characterized in that, The chemical formula is Gd 3-x Er x Al2, in which the rare earth elements are gadolinium (Gd) and erbium (Er), x=0-0.

5.

2. The gadolinium-erbium aluminum soft magnetic material as described in claim 1, characterized in that, x = 0, 0.1, 0.2, 0.3, 0.4 or 0.5, gadolinium-erbium aluminum soft magnetic material is a granular magnetic working fluid.

3. The gadolinium-erbium aluminum soft magnetic material as described in claim 2, characterized in that, The particle size range is 0.08mm-3mm.

4. The gadolinium-erbium aluminum soft magnetic material as described in claim 2, characterized in that, Particulate magnetic working materials are in the form of flakes, granules, or strips.

5. The gadolinium-erbium aluminum soft magnetic material as described in claim 4, characterized in that, The thickness of the sheet-like or strip-shaped magnetic working material ranges from 0.08 mm to 5 mm.

6. The gadolinium-erbium aluminum soft magnetic material as described in claim 1, characterized in that, The Curie temperature range of the working fluid in gadolinium-erbium aluminum soft magnetic material is 131K-279K.

7. The gadolinium-erbium aluminum soft magnetic material as described in claim 1, characterized in that, As the Er content increases, the lattice constant and unit cell volume exhibit a monotonically decreasing trend.

8. The method for preparing gadolinium-erbium aluminum soft magnetic material as described in claim 1, characterized in that, include: According to the chemical formula Gd 3-x Er x Al2 is used as raw material, x=0-0.

5. After being crushed, it is placed in a glass tube, sealed, and evacuated to a negative value. Then, the tube is sealed under inert gas protection. After the glass tube is welded, the glass tube containing gadolinium-erbium aluminum soft magnetic material is placed in a heat treatment furnace for high-temperature heat treatment; the temperature range of the high-temperature heat treatment of gadolinium-erbium aluminum soft magnetic material is 800℃-1150℃, and the heat treatment time is 24h-168h. After quenching, the gadolinium-erbium aluminum soft magnetic material is removed from the glass tube and dried. Then it is crushed in a crusher to obtain granular magnetic working material.

9. The method for preparing gadolinium-erbium aluminum soft magnetic material as described in claim 8, characterized in that, Erbium content increases in the following proportions: 0.1, 0.2, 0.3, 0.4, and 0.5, while gadolinium content decreases accordingly starting from 3. The raw materials are then placed in a vacuum melting furnace to prepare gadolinium-erbium aluminum soft magnetic materials.

10. The method for preparing gadolinium-erbium aluminum soft magnetic material as described in claim 8, characterized in that, When the high-temperature heat treatment reaches the set time, the quartz glass tube is removed and quickly immersed in cold water for quenching. Ice cubes are added to the water before quenching to maintain a low temperature.

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