Preparation method of high-entropy alloy superconducting wire

Abstract

The invention discloses a preparation method of a high-entropy alloy superconducting wire. The method comprises the following steps: 1, cutting out an Nb tube and a Cu tube which are consistent in length and have the outer diameter slightly lower than the inner diameter of the Cu tube; 2, sealing one end of the Nb tube by using a Cu plug, then filling spherical high-entropy superconducting alloy powder, and then plugging by using a Cu plug; thirdly, the Nb-wrapped high-entropy alloy superconducting composite rod is loaded into a Cu pipe; and 4, processing the Cu / Nb composite sheathed high-entropy superconducting alloy composite rod to obtain the high-entropy alloy superconducting wire with superconducting current-carrying performance. The Nb pipe and the Cu pipe which are consistent in length and matched in outer diameter and inner diameter are combined, the composite rod can be processed into the superconducting wire rod more easily, the plastic deformation capacity and the processing efficiency are improved through the spherical high-entropy superconducting alloy powder, the difficulty of plastic deformation is reduced, the high-performance high-entropy alloy superconducting wire rod can be rapidly obtained, and the application range of the high-performance high-entropy alloy superconducting wire rod is widened. And the superconducting current-carrying performance of the high-entropy alloy superconducting wire rod is ensured.

Description

Technical Field

[0001] The invention belongs to the technical field of high entropy superconducting wires, and in particular relates to a method for preparing a high entropy alloy superconducting wire. Background Art

[0002] As an emerging superconducting material, NbTiZrHfTa high entropy alloy has shown a high conductivity of up to 1×10 6 A / cm 2 Its excellent current-carrying capacity indicates that it has broad development prospects in the field of superconductivity.

[0003] Currently, superconducting magnets constitute the largest market for superconducting material applications, and the preparation of superconducting wires is a key step in building superconducting magnets. Traditionally, the process of forming alloys into rods and then plastically deforming them to form wires faces great technical challenges. Although thin film morphology is easy to form, the plastic deformation method shows significant advantages in preparing round wires for magnet winding, cable stranding, and realizing multi-core structures.

[0004] Therefore, developing a new method that can effectively improve the plastic deformation ability of high-entropy alloys and thus efficiently prepare superconducting wires has become a core issue that needs to be urgently addressed in the current field of high-entropy superconducting alloy wire research. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a method for preparing a high entropy alloy superconducting wire in view of the deficiencies of the above-mentioned prior art. The method uses a combination of a Nb tube and a Cu tube of the same length and matching outer diameter and inner diameter, which makes it easier to process a composite rod into a superconducting wire, uses a spherical high entropy superconducting alloy powder to improve the deformation ability of the powder, and uses the formation of Cu encapsulating Nb and then encapsulating the high entropy superconducting alloy powder to ensure that the high entropy alloy superconducting wire has superconducting current carrying performance, and it is easier to obtain a thinner high entropy alloy superconducting wire with superconducting current carrying performance.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is: a method for preparing a high entropy alloy superconducting wire, characterized in that the method comprises the following steps:

[0007] Step 1, preparation of Nb tube and Cu tube: cutting Nb tube and Cu tube of the same length, wherein the outer diameter of the Nb tube is slightly smaller than the inner diameter of the Cu tube, and then cleaning them to obtain the cleaned Nb tube and Cu tube;

[0008] Step 2: Loading spherical high-entropy superconducting alloy powder into Nb tube: Seal one end of the cleaned Nb tube obtained in Step 1 with a Cu plug, then load the spherical high-entropy superconducting alloy powder, and then seal the other end of the cleaned Nb tube with a Cu plug to complete the powder loading into the tube, obtaining a high-entropy alloy superconducting composite rod with an Nb sheath.

[0009] Step 3: Sheathing: Load the high-entropy alloy superconducting composite rod with an Nb sheath obtained in Step 2 into the cleaned Cu tube obtained in Step 1 to obtain a high-entropy superconducting alloy composite rod with a Cu / Nb composite sheath.

[0010] Step 4: Wire processing: Process the high-entropy superconducting alloy composite rod with a Cu / Nb composite sheath obtained in Step 3 to obtain a high-entropy alloy superconducting wire with superconducting current-carrying performance.

[0011] The present invention combines Nb tubes and Cu tubes with consistent lengths and matching outer and inner diameters. The role of the Cu tube is the stabilizer of the superconducting wire, having a good current shunting effect, and the processing plasticity of Cu is very good, serving as a support for plastic deformation during processing, thus making it easier to process the composite rod into a superconducting wire. The role of the Nb tube is a barrier layer, which can prevent the spherical high-entropy superconducting alloy powder with high strength from being pressed into the Cu layer during the plastic deformation process of processing, improving the processing plasticity of Cu. By using Cu plugs for sealing and plugging to prevent the spherical high-entropy superconducting alloy powder from leaking out, the present invention uses spherical high-entropy superconducting alloy powder, which has good fluidity, improves the plasticity of the wire to a certain extent, and is conducive to the plastic processing of the wire. The present invention adopts the form of Cu wrapping Nb and then wrapping high-entropy superconducting alloy powder to obtain a high-entropy alloy superconducting wire, ensuring that the high-entropy alloy superconducting wire has superconducting current-carrying performance.

[0012] For the above-mentioned method for preparing a high-entropy alloy superconducting wire, it is characterized in that in Step 1, the outer diameter of the Cu tube is 5 mm to 20 mm, the wall thickness is 1 mm to 3 mm, and the length is 200 mm to 1000 mm. The outer diameter of the Nb tube is 0.1 mm to 0.3 mm smaller than the inner diameter of the Cu tube, and the wall thickness is 1 mm to 3 mm. The present invention controls the dimensions of the Cu tube and the Nb tube to ensure the proportion of Cu, Nb, and high-entropy alloy in the high-entropy alloy superconducting wire, thereby ensuring the superconducting current-carrying performance of the high-entropy alloy superconducting wire, and enabling the high-entropy superconducting alloy composite rod with a Cu / Nb composite sheath to be processed smoothly into a high-entropy alloy superconducting wire with superconducting current-carrying performance.

[0013] The above-mentioned method for preparing a high-entropy alloy superconducting wire is characterized in that the cleaning process in step one is as follows: cleaning the oil stain on the surface with a metal cleaning agent, then cleaning the metal oxide on the surface with a nitric acid solution, then cleaning the residual acid solution on the surface with deionized water, and finally drying it with a hair dryer. The present invention fully removes the oil stain, metal oxide, residual acid solution and residual deionized water by controlling the cleaning process, prevents the introduction of impurities, and ensures the performance of the high-entropy alloy superconducting wire.

[0014] The above-mentioned method for preparing a high-entropy alloy superconducting wire is characterized in that the process of loading the spherical high-entropy superconducting alloy powder into the Nb tube in step two is as follows: loading the spherical high-entropy superconducting alloy powder with a spatula, and pressing the newly loaded powder with a Cu rod every time a spatula of powder is loaded. In the present invention, the newly loaded powder is pressed with a Cu rod every time a spatula of powder is loaded, which avoids uneven problems such as partial empty tubes caused by too much powder being placed in the middle when loading powder at one time, and ensures the performance of the high-entropy alloy superconducting wire.

[0015] The above-mentioned method for preparing a high-entropy alloy superconducting wire is characterized in that the process of loading the spherical high-entropy superconducting alloy powder into the Nb tube stops when the distance from the tube mouth is 4 mm to 6 mm in step two. The present invention provides a position for the installation of the Cu plug by controlling the distance from the tube mouth when the spherical high-entropy superconducting alloy powder is loaded into the Nb tube.

[0016] The above-mentioned method for preparing a high-entropy alloy superconducting wire is characterized in that the length of the Cu plug in step two is 4 mm to 6 mm. The present invention ensures the effective sealing effect of the Cu plug by controlling the length of the Cu plug and combining with the distance from the tube mouth when the spherical high-entropy superconducting alloy powder is loaded into the Nb tube. At the same time, it ensures that the Cu plug can stably exist during the plastic deformation process of the composite rod during processing, avoiding the problem of the spherical high-entropy superconducting alloy powder flowing out caused by the damage of the Cu plug. Moreover, using a shorter Cu plug indicates that more spherical high-entropy superconducting alloy powder can be loaded into the Nb tube, so that longer superconducting wires can be prepared, improving the yield of the superconducting wire.

[0017] The above-mentioned method for preparing a high-entropy alloy superconducting wire is characterized in that the processing process in step four is as follows: performing multiple plastic deformations on the high-entropy superconducting alloy composite rod with a Cu / Nb composite sheath with a pass processing amount of 10% to 15% to obtain a high-entropy alloy superconducting wire with a superconducting current-carrying performance and a diameter of 1 mm to 4 mm. The present invention is beneficial to the flow of the spherical high-entropy superconducting alloy powder by using a smaller pass processing amount, and is conducive to processing a high-entropy alloy superconducting wire with a superconducting current-carrying performance and a diameter of 1 mm to 4 mm, meeting the wire diameter requirements for magnet winding.

[0018] The above method for preparing a high-entropy alloy superconducting wire is characterized in that in step four, the current-carrying performance of the high-entropy alloy superconducting wire with superconducting current-carrying performance is higher than 5000 A / cm 2 The high-entropy alloy superconducting wire prepared by the present invention has excellent superconducting current-carrying performance.

[0019] The present invention has the following advantages compared with the prior art:

[0020] 1. The present invention combines Nb tubes and Cu tubes with consistent lengths and matching outer and inner diameters, making it easier to process the composite rod into a superconducting wire, and can avoid the high-strength spherical high-entropy superconducting alloy powder being pressed into the Cu layer during the plastic deformation process of processing. By adopting the form of Cu wrapping Nb and then wrapping the high-entropy superconducting alloy powder, a high-entropy alloy superconducting wire is obtained, ensuring that the high-entropy alloy superconducting wire has superconducting current-carrying performance.

[0021] 2. The present invention uses spherical high-entropy superconducting alloy powder to improve the deformation ability of the powder. Moreover, when the spherical high-entropy superconducting alloy powder is processed, not only plastic deformation occurs, but also there is a certain amount of rolling. Therefore, the plastic deformation of the composite rod is relatively simple, and it is easier to obtain a thinner high-entropy alloy superconducting wire with superconducting current-carrying performance, meeting the wire diameter requirements for winding the magnet.

[0022] 3. The present invention uses spherical high-entropy superconducting alloy powder, which can be loaded into a thinner Nb tube for processing. Therefore, the initial size of the superconducting wire is small, and a high-entropy alloy superconducting wire with the final size and superconducting current-carrying performance can be obtained through a very small amount of processing, further reducing the difficulty of plastic deformation.

[0023] 4. The preparation method of the present invention is simple and efficient, and can quickly obtain a high-entropy alloy superconducting wire with superconducting current-carrying performance.

[0024] The technical solution of the present invention will be further described in detail below with reference to the drawings and embodiments. Description of the Drawings

[0025] Figure 1 is the preparation process of the high-entropy alloy superconducting wire with superconducting current-carrying performance of the present invention. Detailed Embodiments

[0026] Example 1

[0027] This example includes the following steps:

[0028] Step 1. Preparation of Nb tube and Cu tube: Cut a Cu tube with an outer diameter of 10 mm, a wall thickness of 2 mm, and a length of 500 mm, and an Nb tube with an outer diameter 0.2 mm smaller than the inner diameter of the Cu tube, a wall thickness of 2 mm, and a length of 500 mm. Then, use 1 mol / L metal cleaning agent to clean the oil stains on the surface, and then use 0.1 mol / L nitric acid solution to clean the metal oxides on the surface. Then, wash off the residual acid solution on the surface with deionized water, and finally dry it with a hair dryer to obtain the cleaned Nb tube and Cu tube;

[0029] Step 2. Loading spherical high-entropy superconducting alloy powder into the Nb tube: Seal one end of the cleaned Nb tube obtained in Step 1 with a Cu plug with a length of 5 mm. Then, use a spatula to load spherical NbTiZrHfTa high-entropy superconducting alloy powder, and use a Cu rod to press the newly loaded powder every time a spatula of powder is loaded. Stop loading the powder when the spherical NbTiZrHfTa high-entropy superconducting alloy powder is 5 mm away from the pipe orifice in the Nb tube, and then use a Cu plug with a length of 5 mm to block the other end to complete the powder loading into the tube, and obtain a high-entropy alloy superconducting composite rod with an Nb sheath;

[0030] Step 3. Sheathing: Load the high-entropy alloy superconducting composite rod with an Nb sheath obtained in Step 2 into the cleaned Cu tube obtained in Step 1 to obtain a high-entropy superconducting alloy composite rod with a Cu / Nb composite sheath;

[0031] Step 4. Wire processing: Perform multiple plastic deformations on the high-entropy superconducting alloy composite rod with a Cu / Nb composite sheath obtained in Step 3 with a pass processing amount of 12% to obtain a high-entropy alloy superconducting wire with a diameter of 2 mm and superconducting current-carrying performance.

[0032] After testing, the current-carrying performance of the high-entropy alloy superconducting wire prepared in this example is higher than 5000 A / cm 2 , and the high-entropy alloy superconducting wire with superconducting current-carrying performance prepared in this example is analyzed by scanning electron microscopy. Metallurgical bonding has been formed between the high-entropy alloy superconducting core wires and the high-entropy alloy powders, and the core wire sizes are uniform, without obvious holes or crack defects. The high-entropy alloy superconducting core wires are dense and uniform, so that the superconducting current can flow unobstructed in the high-entropy alloy superconducting core wires. Therefore, this high-entropy alloy superconducting wire has very high superconducting current-carrying performance.

[0033] Example 2

[0034] This example includes the following steps:

[0035] Step 1. Preparation of Nb tube and Cu tube: Cut a Cu tube with an outer diameter of 5 mm, a wall thickness of 1 mm, and a length of 200 mm, and an Nb tube with an outer diameter 0.1 mm smaller than the inner diameter of the Cu tube, a wall thickness of 1 mm, and a length of 200 mm. Then, clean the oil stains on the surface with 1 mol / L metal cleaning agent, then clean the metal oxides on the surface with 0.1 mol / L nitric acid solution, then wash off the residual acid solution on the surface with deionized water, and finally dry it with a hair dryer to obtain the cleaned Nb tube and Cu tube;

[0036] Step 2. Loading spherical high-entropy superconducting alloy powder into the Nb tube: Seal one end of the cleaned Nb tube obtained in Step 1 with a Cu plug with a length of 4 mm, then use a spatula to load spherical NbTiZrHfTa high-entropy superconducting alloy powder, and press the newly loaded powder with a Cu rod every time a spatula of powder is loaded. Stop loading the tube when the spherical NbTiZrHfTa high-entropy superconducting alloy powder is 4 mm away from the tube orifice in the Nb tube, and then seal the other end with a Cu plug with a length of 4 mm to complete the powder loading into the tube, and obtain a high-entropy alloy superconducting composite rod with an Nb sheath;

[0037] Step 3. Sheathing: Load the high-entropy alloy superconducting composite rod with an Nb sheath obtained in Step 2 into the cleaned Cu tube obtained in Step 1 to obtain a high-entropy superconducting alloy composite rod with a Cu / Nb composite sheath;

[0038] Step 4. Wire processing: Perform multiple plastic deformations on the high-entropy superconducting alloy composite rod with a Cu / Nb composite sheath obtained in Step 3 with a per-pass processing amount of 10% to obtain a high-entropy alloy superconducting wire with a diameter of 1 mm and superconducting current-carrying performance.

[0039] After testing, the current-carrying performance of the high-entropy alloy superconducting wire prepared in this example is higher than 5000 A / cm 2 , and through scanning electron microscope analysis of the high-entropy alloy superconducting wire with superconducting current-carrying performance prepared in this example, it is found that metallurgical bonding has been formed between the high-entropy alloy superconducting core wires and the high-entropy alloy powder, and the core wire sizes are uniform, without obvious hole and crack defects. The high-entropy alloy superconducting core wires are dense and uniform, so that the superconducting current can flow unobstructed in the high-entropy alloy superconducting core wires. Therefore, this high-entropy alloy superconducting wire has very high superconducting current-carrying performance.

[0040] Example 3

[0041] This example includes the following steps:

[0042] Step 1. Preparation of Nb tube and Cu tube: Cut a Cu tube with an outer diameter of 20 mm, a wall thickness of 3 mm, and a length of 1000 mm, and an Nb tube with an outer diameter 0.3 mm smaller than the inner diameter of the Cu tube, a wall thickness of 3 mm, and a length of 1000 mm. Then, clean the surface oil stains with 1 mol / L metal cleaning agent, then clean the surface metal oxides with 0.1 mol / L nitric acid solution, then wash off the residual acid solution on the surface with deionized water, and finally dry it with a hair dryer to obtain the cleaned Nb tube and Cu tube;

[0043] Step 2. Loading spherical high-entropy superconducting alloy powder into the Nb tube: Seal one end of the cleaned Nb tube obtained in Step 1 with a Cu plug with a length of 6 mm, then use a spatula to load spherical NbTiZrHfTa high-entropy superconducting alloy powder, and press the newly loaded powder with a Cu rod every time a spatula of powder is loaded. Stop loading the powder into the Nb tube when the distance from the powder to the tube opening is 6 mm, and then seal the other end with a Cu plug with a length of 6 mm to complete the powder loading into the tube, obtaining an Nb-sheathed high-entropy alloy superconducting composite rod;

[0044] Step 3. Sheathing: Load the Nb-sheathed high-entropy alloy superconducting composite rod obtained in Step 2 into the cleaned Cu tube obtained in Step 1 to obtain a Cu / Nb composite-sheathed high-entropy superconducting alloy composite rod;

[0045] Step 4. Wire processing: Perform multiple plastic deformations on the Cu / Nb composite-sheathed high-entropy superconducting alloy composite rod obtained in Step 3 with a pass processing amount of 15% to obtain a high-entropy alloy superconducting wire with a diameter of 4 mm and superconducting current-carrying performance.

[0046] After testing, the current-carrying performance of the high-entropy alloy superconducting wire prepared in this embodiment is higher than 5000 A / cm 2 , and the high-entropy alloy superconducting wire with superconducting current-carrying performance prepared in this embodiment is analyzed by scanning electron microscopy. Metallurgical bonding has been formed between the high-entropy alloy superconducting core wires and the high-entropy alloy powders, and the core wire sizes are uniform, without obvious holes and crack defects. The high-entropy alloy superconducting core wires are dense and uniform, so that superconducting current can flow unobstructed in the high-entropy alloy superconducting core wires. Therefore, this high-entropy alloy superconducting wire has very high superconducting current-carrying performance.

[0047] The above is only a preferred embodiment of the present invention and does not impose any limitation on the present invention. Any simple modification, change, and equivalent change made to the above embodiments according to the technical essence of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A preparation method of a high-entropy alloy superconducting wire, characterized in that, The method includes the following steps: Step 1. Preparation of Nb tube and Cu tube: Cut Nb tube and Cu tube with the same length, and the outer diameter of the Nb tube is slightly lower than the inner diameter of the Cu tube. Then clean them to obtain the cleaned Nb tube and Cu tube; Step 2. Loading spherical high-entropy superconducting alloy powder into the Nb tube: Seal one end of the cleaned Nb tube obtained in Step 1 with a Cu plug, then load the spherical high-entropy superconducting alloy powder, and seal the other end with a Cu plug to complete powder loading into the tube, obtaining a high-entropy alloy superconducting composite rod with an Nb sheath; Step 3. Sheathing: Load the high-entropy alloy superconducting composite rod with an Nb sheath obtained in Step 2 into the cleaned Cu tube obtained in Step 1 to obtain a high-entropy superconducting alloy composite rod with a Cu / Nb composite sheath; Step 4. Wire processing: Process the high-entropy alloy superconducting composite rod with a Cu / Nb composite sheath obtained in Step 3 to obtain a high-entropy alloy superconducting wire with superconducting current-carrying performance.

2. The preparation method of a high-entropy alloy superconducting wire according to claim 1, characterized in that, In Step 1, the outer diameter of the Cu tube is 5 mm to 20 mm, the wall thickness is 1 mm to 3 mm, the length is 200 mm to 1000 mm, the outer diameter of the Nb tube is 0.1 mm to 0.3 mm smaller than the inner diameter of the Cu tube, and the wall thickness is 1 mm to 3 mm.

3. The preparation method of a high-entropy alloy superconducting wire according to claim 1, characterized in that, The cleaning process in Step 1 is as follows: Clean the surface oil stain with a metal cleaning agent, then clean the surface metal oxide with a nitric acid solution, then wash off the residual acid solution on the surface with deionized water, and finally dry it with a hair dryer.

4. The preparation method of a high-entropy alloy superconducting wire according to claim 1, characterized in that, The process of loading the spherical high-entropy superconducting alloy powder into the Nb tube in Step 2 is as follows: Load the spherical high-entropy superconducting alloy powder with a spatula, and press the newly loaded powder with a Cu rod every time a spatula of powder is loaded.

5. The preparation method of a high-entropy alloy superconducting wire according to claim 1, characterized in that, Stop loading the spherical high-entropy superconducting alloy powder into the Nb tube when the distance from the powder to the tube opening is 4 mm to 6 mm in Step 2.

6. The preparation method of a high-entropy alloy superconducting wire according to claim 5, characterized in that, The length of the Cu plug in Step 2 is 4 mm to 6 mm.

7. The preparation method of a high-entropy alloy superconducting wire according to claim 2, characterized in that, The processing process in Step 4 is as follows: Perform multiple plastic deformations on the high-entropy alloy superconducting composite rod with a Cu / Nb composite sheath with a pass processing amount of 10% to 15% to obtain a high-entropy alloy superconducting wire with a diameter of 1 mm to 4 mm and superconducting current-carrying performance.

8. The preparation method of a high-entropy alloy superconducting wire according to claim 1, characterized in that, The current-carrying performance of the high-entropy alloy superconducting wire with superconducting current-carrying performance described in Step 4 is higher than 5000 A / cm 2 .

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