Rare earth high-entropy alloy-carbon composite fiber wave-absorbing agent, wave-absorbing material and preparation method thereof
By combining electrospinning technology with heat treatment, a rare-earth high-entropy alloy-carbon composite fiber microwave absorber was prepared, solving the problems of uneven distribution of alloying elements and excessively large particle size in traditional methods, and realizing a highly efficient and lightweight electromagnetic wave absorbing material.
Patent Information
- Application Number
- CN202511152441.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-18
- Publication Date
- 2025-11-21
AI Technical Summary
Traditional methods for preparing high-entropy alloy-carbon composite materials suffer from problems such as uneven distribution of alloying elements and excessively large alloy particle size, which affect the absorption performance and make it difficult to achieve efficient and lightweight electromagnetic wave absorption.
Rare earth high-entropy alloy-carbon composite fiber microwave absorber was prepared by electrospinning technology. By combining electrospinning with heat treatment, a composite material of rare earth high-entropy alloy nanoparticles and carbon nanofibers was prepared to form a protective layer and improve the chemical stability and electromagnetic wave attenuation capability of the material.
A rare-earth high-entropy alloy-carbon composite fiber microwave absorber was developed with low density and high microwave absorption performance, featuring thinness, lightness, and broadband absorption characteristics, making it suitable for large-scale production.
Smart Images
Figure CN120989830A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of microwave absorbing materials technology, and in particular to a rare earth high-entropy alloy-carbon composite fiber microwave absorbing agent, microwave absorbing material and its preparation method. Background Technology
[0002] With the rapid development of electronic devices and communication technologies, the research and development of electromagnetic wave absorbing materials has attracted widespread attention. High-entropy alloys, with their unique properties and synergistic effects of multiple elements, have become a key raw material for electromagnetic wave absorbing materials. However, single high-entropy alloys exhibit strong metallic properties and have drawbacks such as high density and poor chemical stability, which limit their application in the field of absorbing materials. Therefore, there is an urgent need to develop efficient high-entropy alloy-based absorbing materials with the characteristics of being "thin, light, wide, and strong".
[0003] Magnetic-carbon composite materials can achieve ideal impedance matching through the synergistic effect of magnetic and dielectric losses, as well as multi-dimensional and multi-scale morphological features, and can also overcome the high density of traditional magnetic materials. Combining high-entropy alloy nanoparticles with carbon materials can not only reduce the overall density but also significantly improve the chemical stability of the composite material. However, traditional methods for preparing high-entropy alloy-carbon composite materials have many problems. For example, high-temperature heat treatment techniques often fail to achieve a uniform distribution of alloying elements, easily inducing phase separation in the high-entropy alloy; mechanical alloying methods usually result in excessively large alloy particle sizes, thereby weakening the interfacial bonding strength of the composite material and further affecting its microwave absorption performance. Therefore, developing a method for preparing high-entropy alloy-carbon composite materials that can effectively solve the above problems has become a core research issue.
[0004] Electrospinning technology, as an emerging process, can effectively control the composition and microstructure of one-dimensional materials by finely adjusting the composition and ratio of the precursor solution, providing a feasible path for designing and developing one-dimensional magnetic electromagnetic wave absorbing materials with specific properties.
[0005] The preparation of high-entropy alloy-carbon composite materials using electrospinning technology is expected to solve the problems of uneven distribution of alloying elements and excessively large alloy particle size in traditional high-entropy alloy-carbon composite materials, which is of great significance for the application of high-entropy alloys in microwave absorbing materials. Summary of the Invention
[0006] The purpose of this invention is to provide a rare earth high-entropy alloy-carbon composite fiber microwave absorbing agent, microwave absorbing material and its preparation method, addressing the shortcomings of existing technologies.
[0007] To achieve the above-mentioned objectives, the present invention provides the following technical solution:
[0008] This invention provides a method for preparing a rare-earth high-entropy alloy-carbon composite fiber microwave absorber, comprising the following steps:
[0009] 1) Iron salts, cobalt salts, nickel salts, manganese salts, copper salts, rare earth nitrates, polyacrylonitrile and solvents are mixed and electrospun to obtain nanofiber membranes.
[0010] 2) The nanofiber membrane is subjected to pre-oxidation and carbonization treatment in sequence to obtain rare earth high entropy alloy-carbon composite fiber microwave absorber.
[0011] The rare earth elements in the rare earth nitrate include one or more of lanthanum, neodymium, and lutetium.
[0012] Preferably, the iron salt in step 1) comprises one or more of ferric nitrate, ferric chloride and ferric sulfate; the cobalt salt comprises one or more of cobalt acetate, cobalt nitrate and cobalt sulfate; the nickel salt comprises one or more of nickel acetate, nickel nitrate and nickel sulfate; the manganese salt comprises one or more of manganese acetate, manganese nitrate and manganese sulfate; and the copper salt comprises one or more of copper acetate, copper nitrate and copper sulfate.
[0013] The solvent is N,N-dimethylformamide and / or anhydrous ethanol.
[0014] Preferably, the molar ratio of iron salt, cobalt salt, nickel salt, manganese salt, copper salt and rare earth nitrate in step 1) is 0.1-1: 0.1-1: 0.1-1: 0.1-1: 0-0.2: 0.01-0.4;
[0015] The molar mass ratio of the iron salt to polyacrylonitrile is 0.05–0.25 mmol: 1–7 g;
[0016] The mass-to-volume ratio of the polyacrylonitrile to the solvent is 1–7 g: 10–40 mL.
[0017] Preferably, the positive voltage of electrospinning in step 1) is 10-30kV, the negative voltage of electrospinning is -5--1kV, the advancing speed of electrospinning is 0.05-0.4mm / min, the receiving distance of electrospinning is 5-20cm, and the receiving speed of electrospinning is 10-40rpm.
[0018] Preferably, the temperature of the pre-oxidation treatment in step 2) is 200-400°C, and the time of the pre-oxidation treatment is 1-6 hours.
[0019] Preferably, the carbonization temperature in step 2) is 800–1200°C, and the carbonization time is 1–6 h.
[0020] The present invention also provides a rare earth high-entropy alloy-carbon composite fiber microwave absorber prepared by the aforementioned preparation method.
[0021] The present invention also provides a microwave absorbing material comprising paraffin, petroleum ether and a microwave absorbing agent;
[0022] The microwave absorbing agent is the rare earth high-entropy alloy-carbon composite fiber microwave absorbing agent.
[0023] Preferably, the microwave absorbing agent has a mass of 5-30% of the paraffin wax mass, and the mass ratio of the paraffin wax to petroleum ether is 0.05-0.25:0.1-0.4.
[0024] The present invention also provides a method for preparing the aforementioned microwave absorbing material, wherein paraffin, microwave absorbing agent, and petroleum ether are mixed sequentially and then pressed.
[0025] The beneficial effects of this invention are:
[0026] 1) This invention successfully prepared rare earth high-entropy alloy-carbon composite fiber microwave absorber by combining electrospinning technology with heat treatment process. The preparation process is safe, easy to operate, has a short production cycle and low cost, and is suitable for large-scale production.
[0027] 2) The rare earth high entropy alloy-carbon composite fiber microwave absorber of the present invention is composed of rare earth high entropy alloy nanoparticles and carbon nanofibers. A carbon nanofiber protective layer is formed on the surface of the rare earth high entropy alloy nanoparticles, which significantly improves the corrosion resistance and oxidation resistance of the rare earth high entropy alloy nanoparticles. At the same time, the rare earth high entropy alloy nanoparticles significantly improve the impedance matching performance and electromagnetic wave attenuation capability of carbon nanofibers, realizing effective control of the electromagnetic parameters of the composite material, exhibiting strong microwave absorption capability, wide frequency range and low density characteristics.
[0028] 3) The absorbing material of the present invention has the characteristics of being lightweight, thin, having a wide absorption bandwidth, and strong absorption capacity. Attached Figure Description
[0029] Figure 1 The X-ray diffraction patterns of the absorbing agents prepared in Examples 1-3 and Comparative Example 1 are shown below.
[0030] Figure 2 A scanning electron microscope image of the microwave absorbing agent prepared in Example 1;
[0031] Figure 3 Scanning electron microscope image of the microwave absorbing agent prepared in Example 2;
[0032] Figure 4 A scanning electron microscope image of the microwave absorbing agent prepared in Example 3;
[0033] Figure 5 Scanning electron microscope image of the microwave absorber prepared in Comparative Example 1;
[0034] Figure 6 To demonstrate the microwave absorption performance of the microwave absorbing material in Example 1;
[0035] Figure 7 To demonstrate the microwave absorption performance of the microwave absorbing material in Example 2;
[0036] Figure 8 To demonstrate the microwave absorption performance of the microwave absorbing material in Example 3;
[0037] Figure 9 To demonstrate the microwave absorption performance of the microwave absorbing material in Example 4;
[0038] Figure 10 To demonstrate the microwave absorption performance of the microwave absorbing material in Comparative Example 1. Detailed Implementation
[0039] This invention provides a method for preparing a rare-earth high-entropy alloy-carbon composite fiber microwave absorber, comprising the following steps:
[0040] 1) Iron salts, cobalt salts, nickel salts, manganese salts, copper salts, rare earth nitrates, polyacrylonitrile and solvents are mixed and electrospun to obtain nanofiber membranes.
[0041] 2) The nanofiber membrane is subjected to pre-oxidation and carbonization treatment in sequence to obtain rare earth high entropy alloy-carbon composite fiber microwave absorber.
[0042] The rare earth elements in the rare earth nitrate include one or more of lanthanum, neodymium, and lutetium.
[0043] In this invention, the iron salt in step 1) preferably includes one or more of ferric nitrate, ferric chloride, and ferric sulfate; the cobalt salt preferably includes one or more of cobalt acetate, cobalt nitrate, and cobalt sulfate; the nickel salt preferably includes one or more of nickel acetate, nickel nitrate, and nickel sulfate; the manganese salt preferably includes one or more of manganese acetate, manganese nitrate, and manganese sulfate; and the copper salt preferably includes one or more of copper acetate, copper nitrate, and copper sulfate.
[0044] The solvent is preferably N,N-dimethylformamide and / or anhydrous ethanol.
[0045] In this invention, the molar ratio of iron salt, cobalt salt, nickel salt, manganese salt, copper salt, and rare earth nitrate in step 1) is preferably 0.1-1:0.1-1:0.1-1:0.1-1:0-0.2:0.01-0.4, more preferably 0.2-0.8:0.2-0.8:0.2-0.8:0.18-0.8:0.02-0.15:0.04-0.3, and even more preferably 0.4-0.6:0.4-0.6:0.4-0.6:0.4-0.6:0.05-0.1:0.1-0.2;
[0046] The molar ratio of the iron salt to polyacrylonitrile is preferably 0.05–0.25 mmol: 1–7 g, more preferably 0.1–0.2 mmol: 2–6 g, and even more preferably 0.15 mmol: 3.2–5 g;
[0047] The preferred mass-to-volume ratio of the polyacrylonitrile to the solvent is 1–7 g: 10–40 mL, more preferably 2–6 g: 20–30 mL, and even more preferably 3.2–5 g: 25–28 mL.
[0048] In this invention, the positive voltage of electrospinning in step 1) is preferably 10-30kV, more preferably 17-25kV, and even more preferably 20kV; the negative voltage of electrospinning is preferably -5--1kV, more preferably -4--2kV, and even more preferably -3--2.5kV; the advancing speed of electrospinning is preferably 0.05-0.4mm / min, more preferably 0.09-0.3mm / min, and even more preferably 0.15-0.2mm / min; the receiving distance of electrospinning is preferably 5-20cm, more preferably 10-15cm, and even more preferably 13cm; the receiving rotation speed of electrospinning is preferably 10-40rpm, more preferably 20-30rpm, and even more preferably 25rpm.
[0049] In this invention, the temperature of the pre-oxidation treatment in step 2) is preferably 200-400℃, more preferably 240-350℃, and even more preferably 300℃; the time of the pre-oxidation treatment is preferably 1-6h, more preferably 2-5h, and even more preferably 3-4h.
[0050] In this invention, the carbonization temperature in step 2) is preferably 800-1200℃, more preferably 900-1100℃, and even more preferably 1000℃; the carbonization time is preferably 1-6h, more preferably 2-5h, and even more preferably 3-4h.
[0051] In this invention, the carbonization process in step 2) is preferably carried out in a mixed atmosphere, which preferably contains nitrogen and hydrogen, and the volume ratio of nitrogen to hydrogen is preferably 90-98:2-10, more preferably 95:5.
[0052] The present invention also provides a rare earth high-entropy alloy-carbon composite fiber microwave absorber prepared by the aforementioned preparation method.
[0053] In this invention, the diameter of the rare earth high-entropy alloy-carbon composite fiber microwave absorber is preferably 0.5 to 2 μm, and more preferably 1 to 1.5 μm.
[0054] The present invention also provides a microwave absorbing material comprising paraffin, petroleum ether and a microwave absorbing agent;
[0055] The microwave absorbing agent is the rare earth high-entropy alloy-carbon composite fiber microwave absorbing agent.
[0056] In this invention, the mass of the microwave absorbing agent is preferably 5-30% of the mass of paraffin, more preferably 10-25%, and even more preferably 20%; the mass ratio of paraffin to petroleum ether is preferably 0.05-0.25:0.1-0.4, more preferably 0.08-0.2:0.2-0.3, and even more preferably 0.09-0.15:0.25.
[0057] The present invention also provides a method for preparing the aforementioned microwave absorbing material, wherein paraffin, microwave absorbing agent, and petroleum ether are mixed sequentially and then pressed.
[0058] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.
[0059] Example 1
[0060] 28 mL of N,N-dimethylformamide was placed in a 60°C constant temperature water bath. 3.2 g of polyacrylonitrile was added to the N,N-dimethylformamide, and the mixture was magnetically stirred at 60 rpm for 4 h to form a homogeneous colloid. 0.2 mmol of ferric nitrate, 0.2 mmol of cobalt nitrate, 0.2 mmol of nickel acetate, 0.18 mmol of manganese nitrate, 0.02 mmol of copper acetate, and 0.04 mmol of lanthanum nitrate were added sequentially to the homogeneous colloid, and the mixture was magnetically stirred at 80 rpm for 24 h to obtain the electrospinning precursor solution.
[0061] 10 mL of the electrospinning precursor solution was drawn using a 10 mL syringe, and electrospinning was performed to obtain nanofiber membranes. The electrospinning parameters were set as follows: positive voltage of 17 kV, negative voltage of -2.5 kV, feed speed of 0.2 mm / min, receiving distance of 13 cm, and receiving rotation speed of 30 rpm.
[0062] The nanofiber membrane was pre-oxidized at 240℃ for 3 hours, and then placed in a nitrogen and hydrogen mixed atmosphere with a volume ratio of 95:5 for carbonization at 1000℃ for 3 hours to obtain a rare earth high entropy alloy-carbon composite fiber microwave absorber with a diameter of 1.5 μm.
[0063] Example 2
[0064] The lanthanum nitrate in Example 1 was replaced with neodymium nitrate, and the receiving distance was changed to 15cm. Everything else was the same as in Example 1.
[0065] Example 3
[0066] The neodymium nitrate in Example 2 was replaced with lutetium nitrate, and everything else was the same as in Example 2.
[0067] Example 4
[0068] 30 mL of N,N-dimethylformamide was placed in a 60 °C constant temperature water bath. 21 g of polyacrylonitrile was added to the N,N-dimethylformamide, and the mixture was magnetically stirred at 50 rpm for 4 h to form a homogeneous colloid. Then, 0.6 mmol of ferric sulfate, 0.6 mmol of cobalt sulfate, 0.6 mmol of nickel nitrate, 0.6 mmol of manganese acetate, 0.1 mmol of copper nitrate, and 0.2 mmol of lanthanum nitrate were added sequentially to the homogeneous colloid, and the mixture was magnetically stirred at 90 rpm for 24 h to obtain an electrospinning precursor solution.
[0069] 10 mL of the electrospinning precursor solution was drawn using a 10 mL syringe, and electrospinning was performed to obtain nanofiber membranes. The electrospinning parameters were set as follows: positive voltage of 10 kV, negative voltage of -5 kV, feed speed of 0.4 mm / min, receiving distance of 20 cm, and receiving rotation speed of 10 rpm.
[0070] The nanofiber membrane was pre-oxidized at 400℃ for 1 h, and then placed in a nitrogen and hydrogen mixed atmosphere with a volume ratio of 95:5 for carbonization at 800℃ for 6 h to obtain a rare earth high entropy alloy-carbon composite fiber microwave absorber with a diameter of 1.2 μm.
[0071] Example 5
[0072] 320 mL of N,N-dimethylformamide was placed in a 60 °C constant temperature water bath. 8 g of polyacrylonitrile was added to the N,N-dimethylformamide, and the mixture was magnetically stirred at 40 rpm for 4 h to form a homogeneous colloid. Then, 0.8 mmol of ferric nitrate, 0.8 mmol of cobalt nitrate, 0.8 mmol of nickel acetate, 0.8 mmol of manganese nitrate, 0.2 mmol of copper acetate, and 0.4 mmol of lanthanum nitrate were added sequentially to the homogeneous colloid, and the mixture was magnetically stirred at 100 rpm for 24 h to obtain the electrospinning precursor solution.
[0073] 10 mL of the electrospinning precursor solution was drawn using a 10 mL syringe, and electrospinning was performed to obtain nanofiber membranes. The electrospinning parameters were set as follows: positive voltage of 30 kV, negative voltage of -1 kV, feed speed of 0.4 mm / min, receiving distance of 5 cm, and receiving rotation speed of 40 rpm.
[0074] The nanofiber membrane was pre-oxidized at 200℃ for 6 hours, and then placed in a nitrogen and hydrogen mixed atmosphere with a volume ratio of 95:5 for carbonization treatment at 1200℃ for 1 hour to obtain a rare earth high entropy alloy-carbon composite fiber microwave absorber with a diameter of 1.5 μm.
[0075] Comparative Example 1
[0076] Lanthanum nitrate was omitted from Example 1, and everything else was the same as in Example 1. The diameter of the high-entropy alloy-carbon composite fiber microwave absorber obtained was 1 μm.
[0077] Figure 1 The X-ray diffraction patterns are those of the absorbing agents prepared in Examples 1-3 and Comparative Example 1. Figure 1 It can be seen that the microwave absorbers prepared in Examples 1-3 and Comparative Example 1 all exhibit the characteristics of coexistence of iron-nickel alloy phase and amorphous carbon phase, and have good crystallinity. Since the rare earth element doping content in Examples 1-3 is low, no rare earth element phase was observed in the X-ray diffraction patterns.
[0078] Figure 2 The image shows a scanning electron microscope (SEM) image of the microwave absorber prepared in Example 1. Figure 3 The image shows a scanning electron microscope (SEM) image of the microwave absorbing agent prepared in Example 2. Figure 4 The image shows a scanning electron microscope (SEM) image of the microwave absorber prepared in Example 3. Figure 5 The image shows a scanning electron microscope (SEM) image of the microwave absorbing agent prepared in Comparative Example 1. Figures 2-5 As can be seen, the rare-earth high-entropy alloy-carbon composite fiber microwave absorbers prepared in Examples 1-3 exhibit a typical fibrous structure, forming a fiber network with multi-dimensional and multi-scale interfaces. It is precisely the presence of these multi-scale interfaces that significantly improves the anti-matching properties of the absorber, while simultaneously generating more dipoles at the interfaces, effectively enhancing its ability to absorb electromagnetic waves.
[0079] Application Example 1
[0080] 0.09g of paraffin wax (purchased from Jinan Jinyingtai Chemical Co., Ltd., chlorinated paraffin-52) and 0.01g of the rare earth high-entropy alloy-carbon composite fiber microwave absorbing agent prepared in Example 1 were mixed evenly, and then 0.2g of petroleum ether was added and mixed evenly. The mixture was placed in a steel ring mold with an outer diameter of 7mm and an inner diameter of 3mm and pressed at 10MPa for 2min to obtain the microwave absorbing material.
[0081] Application Example 2
[0082] Replace the rare earth high entropy alloy-carbon composite fiber microwave absorber in Application Example 1 with the rare earth high entropy alloy-carbon composite fiber microwave absorber prepared in Example 2, and otherwise remain the same as in Application Example 1.
[0083] Application Example 3
[0084] Replace the rare earth high entropy alloy-carbon composite fiber microwave absorber in Application Example 1 with the rare earth high entropy alloy-carbon composite fiber microwave absorber prepared in Example 3, and otherwise remain the same as in Application Example 1.
[0085] Application Example 4
[0086] 0.08g of paraffin wax (purchased from Jinan Jinyingtai Chemical Co., Ltd., chlorinated paraffin-52) and 0.02g of the rare earth high-entropy alloy-carbon composite fiber microwave absorbing agent prepared in Example 3 were mixed evenly, and then 0.2g of petroleum ether was added and mixed evenly. The mixture was placed in a steel ring mold with an outer diameter of 7mm and an inner diameter of 3mm and pressed at 5MPa for 5min to obtain the microwave absorbing material.
[0087] Application Comparative Example 1
[0088] The rare earth high-entropy alloy-carbon composite fiber microwave absorber in Application Example 1 was replaced with the rare earth high-entropy alloy-carbon composite fiber microwave absorber prepared in Comparative Example 1, and everything else was the same as in Application Example 1.
[0089] The microwave absorption performance of the absorbing materials prepared according to Examples 1-4 and Comparative Example 1 was tested. Electromagnetic parameters were measured using the coaxial transmission reflection method, with an Anritsu-MS46322B vector network analyzer used. The test frequency range was 2-18 GHz. The obtained electromagnetic parameters were then used to evaluate the microwave absorption performance of materials with thicknesses of 1-5 mm using the RL Calculator.
[0090] Figure 6 The microwave absorption performance of the microwave absorbing material in Application Example 1 is shown. Figure 7 The microwave absorption performance of the microwave absorbing material in Application Example 2 is shown. Figure 8 The microwave absorption performance of the microwave absorbing material in Example 3 is shown. Figure 9 The microwave absorption performance of the microwave absorbing material in Example 4 is shown. Figure 10 To demonstrate the microwave absorption performance of the microwave absorbing material in Comparative Example 1, [the following is a description of the process]. Figures 6-10 It can be seen that the maximum reflection loss and effective absorption bandwidth of the microwave absorbing materials prepared by the rare earth element doped absorbing agent in Application Examples 1 to 3 are better than those in Application Comparative Example 1.
[0091] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.
Claims
1. A method for preparing a rare-earth high-entropy alloy-carbon composite fiber microwave absorber, characterized in that, It includes the following steps: 1) Iron salts, cobalt salts, nickel salts, manganese salts, copper salts, rare earth nitrates, polyacrylonitrile and solvents are mixed and electrospun to obtain nanofiber membranes. 2) The nanofiber membrane is subjected to pre-oxidation and carbonization treatment in sequence to obtain rare earth high entropy alloy-carbon composite fiber microwave absorber. The rare earth elements in the rare earth nitrate include one or more of lanthanum, neodymium, and lutetium.
2. The preparation method according to claim 1, characterized in that, Step 1) The iron salt contains one or more of ferric nitrate, ferric chloride and ferric sulfate; the cobalt salt contains one or more of cobalt acetate, cobalt nitrate and cobalt sulfate; the nickel salt contains one or more of nickel acetate, nickel nitrate and nickel sulfate; the manganese salt contains one or more of manganese acetate, manganese nitrate and manganese sulfate; and the copper salt contains one or more of copper acetate, copper nitrate and copper sulfate. The solvent is N,N-dimethylformamide and / or anhydrous ethanol.
3. The preparation method according to claim 2, characterized in that, In step 1), the molar ratio of iron salt, cobalt salt, nickel salt, manganese salt, copper salt, and rare earth nitrate is 0.1–1: 0.1–1: 0.1–1: 0.1–1: 0–0.2: 0.01–0.
4. The molar mass ratio of the iron salt to polyacrylonitrile is 0.05–0.25 mmol: 1–7 g; The mass-to-volume ratio of the polyacrylonitrile to the solvent is 1–7 g: 10–40 mL.
4. The preparation method according to any one of claims 1 to 3, characterized in that, In step 1), the positive voltage of electrospinning is 10-30kV, the negative voltage of electrospinning is -5--1kV, the propulsion speed of electrospinning is 0.05-0.4mm / min, the receiving distance of electrospinning is 5-20cm, and the receiving speed of electrospinning is 10-40rpm.
5. The preparation method according to claim 4, characterized in that, Step 2) The temperature of the pre-oxidation treatment is 200-400℃, and the time of the pre-oxidation treatment is 1-6h.
6. The preparation method according to claim 5, characterized in that, Step 2) The carbonization temperature is 800-1200℃ and the carbonization time is 1-6h.
7. The rare earth high-entropy alloy-carbon composite fiber microwave absorber prepared by the preparation method according to any one of claims 1 to 6.
8. A microwave absorbing material, characterized in that, It contains paraffin, petroleum ether, and microwave absorbers; The microwave absorbing agent is the rare earth high-entropy alloy-carbon composite fiber microwave absorbing agent as described in claim 7.
9. The microwave absorbing material according to claim 8, characterized in that, The microwave absorbing agent has a mass of 5-30% of the paraffin wax mass, and the mass ratio of the paraffin wax to petroleum ether is 0.05-0.25:0.1-0.
4.
10. The method for preparing the microwave absorbing material according to claim 8 or 9, characterized in that, Paraffin wax, microwave absorber, and petroleum ether are mixed in sequence and then pressed.