A method for preparing high-entropy carbides

Abstract

This invention provides a method for preparing high-entropy carbides, comprising the following steps: S1: mixing waste tungsten slag with copper converter slag and carbon powder at a mass ratio of 1:(0.6~1.0):(0.06~0.08) until uniform; S2: forming a columnar billet by cold isostatic pressing of the uniformly mixed sample; S3: placing the billet in a crucible, heating it in an inert atmosphere until the sample is completely melted, the melt level drops to 1 / 3 of the crucible height, and adding the billet into the melt multiple times to increase the melt volume to 4 / 5 of the crucible volume, followed by isothermal treatment to obtain a stable melt; S4: aligning the bottom of the crucible with the bottom of the induction coil and moving it downwards to a preset height, repeating this process multiple times to obtain a composite rich in high-entropy carbides and a binder phase; the product obtained by this invention has high strength, corrosion resistance, and wear resistance, and by controlling the addition of external elements, it recovers rare and valuable metals from waste tungsten slag while preparing a high-entropy carbide composite with higher strength and more uniform microstructure.

Description

Technical Field

[0001] This invention relates to the field of high-entropy carbide preparation technology, and specifically to a method for preparing high-entropy carbides. Background Technology

[0002] Due to its excellent properties, cemented carbide has been widely used in recent years. However, with the increasing production volume, the amount of waste products is also increasing year by year. At present, the industry generally uses wet recycling to recycle waste cemented carbide. However, wet recycling has a limited leaching rate and generates a large amount of waste tungsten slag. The accumulation of this waste tungsten slag will cause serious harm to the environment. The waste tungsten slag contains a variety of rare and valuable metal elements, which urgently need to be recycled and reused.

[0003] Existing research indicates that carbothermic reduction smelting can effectively recover rare and valuable metals from waste tungsten slag. However, it suffers from the problems of high smelting temperature and multiple valuable metals being dissolved in the alloy phase, making it difficult to separate individual elements. Furthermore, due to the complex composition of the alloy phase, it is difficult to utilize it directly.

[0004] Copper converter slag, a byproduct of pyrometallurgical copper smelting, contains a large amount of oxides (such as CuO, Fe2O3, NiO, CaO, Al2O3, SiO2, etc.). Direct landfilling of copper converter slag would have a serious impact on environmental safety.

[0005] Based on this, the present invention provides a method for preparing high-entropy carbides using waste tungsten slag and copper converter slag, so as to realize the recycling and high-value utilization of waste tungsten slag and copper converter slag. Summary of the Invention

[0006] To address the aforementioned problems, the present invention aims to provide a method for preparing high-entropy carbides, thereby producing high-hardness high-entropy carbide composites and realizing the recycling and high-value utilization of waste tungsten slag and copper converter slag.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] A method for preparing high-entropy carbides includes the following steps:

[0009] S1: Mix waste tungsten slag with copper converter slag and carbon powder at a mass ratio of 1:(0.6~1.0):(0.06~0.08) until homogeneous;

[0010] S2: The uniformly mixed sample is formed into a columnar blank by cold isostatic pressing;

[0011] S3: Place the billet in a crucible and heat it in an inert atmosphere until the sample is completely melted. The melt level drops to 1 / 3 of the crucible height. Add the billet into the melt multiple times to increase the melt volume to 4 / 5 of the crucible volume. Then perform isothermal treatment to obtain a stable melt.

[0012] S4: Align the bottom of the crucible with the bottom of the induction coil and move it downwards to a preset height. Repeat this process multiple times to obtain a composite rich in high-entropy carbides and a binder phase.

[0013] As one possible implementation, the waste tungsten slag further comprises 5-10% WO3, 1-2% CoO, 4-7% Ta2O5, 3-6% Nb2O5, 1-5% Cr2O3, 40-50% SiO2, and 10-25% TiO2.

[0014] As one possible implementation, the copper converter slag further comprises 15-35% CuO, 15-30% Fe2O3, 10-25% NiO2, 25-30% CaO, 10-20% Al2O3, and 5-15% SiO2.

[0015] As one possible implementation, the maximum pressure of the cold isostatic pressing in S2 is 200 MPa, and the holding time at the maximum pressure is 3 minutes.

[0016] As one possible implementation, the diameter of the columnar blank is 3-4 mm smaller than the inner diameter of the crucible.

[0017] As one possible implementation, further, in step S4, the bottom of the crucible is aligned with the bottom of the induction coil and moved downwards by a predetermined height, specifically including the following steps:

[0018] The bottom of the crucible is flush with the bottom of the induction coil. The crucible is dropped 50 mm at a speed of 1 mm / min, and then dropped again at a speed of 5 mm / min until the top of the crucible is 20 mm below the induction coil.

[0019] As one possible implementation, the power of the induction coil is further 25KW.

[0020] As a preferred embodiment, preferably, in S3 the temperature is increased to 1600±20℃ at a rate of 20℃ / min to completely melt the sample.

[0021] As a preferred implementation method, the constant temperature in S3 is preferably 1600℃ and the constant temperature time is 2h.

[0022] As a preferred implementation method, the number of cycles in S4 is preferably 3.

[0023] The role of copper converter slag in this invention is as follows:

[0024] 1) During the smelting process, CuO, Fe2O3, NiO, Cr2O3, etc., after being reduced by carbon, can act as scavengers to capture high-entropy carbides in the slag, promote the sedimentation of high-entropy carbides, reduce the viscosity of the slag, and improve the recovery rate of rare and valuable metals.

[0025] 2) Regulating the properties of the final product (high-entropy carbide composite): Nickel, as a binder phase, can improve the fracture toughness of the composite; iron, as a binder phase, can improve the machinability and heat treatment performance of the product; cobalt in the raw materials, as a binder phase, has the best wettability, resulting in good strength and toughness. Simultaneously, iron, cobalt, and nickel also have a good synergistic effect, and when all three are used as binders, a composite with excellent overall performance can be obtained.

[0026] The product obtained by this invention is a composite of high-entropy carbide (W,Ta,Nb,Ti,Cr)C and a binder phase. Compared with traditional alloys, it is a new type of material with high strength, corrosion resistance, and wear resistance. By adding external elements to regulate the process, rare and valuable metals in waste tungsten slag are recovered while a high-entropy carbide composite with higher strength and more uniform microstructure is prepared.

[0027] The method proposed in this invention comprises two parts: one is slag-forming smelting to achieve slag-metal phase separation, and the other is directional solidification alloying to achieve phase control. This successfully realizes the recycling and high-value utilization of waste tungsten slag and copper converter slag, which not only solves the current problem of waste tungsten slag accumulation in enterprises but also effectively improves the recycling rate of secondary resources in my country. In addition, this invention successfully prepares high-hardness, high-entropy carbide composites by adding copper converter slag. Compared with traditional preparation methods, its manufacturing cost is low and its mechanical properties are better.

[0028] The beneficial effects of this invention are as follows:

[0029] 1) High recovery rate: The total recovery rate of valuable metals in waste tungsten slag can reach 90% in this invention. It can be used as a supplement to the process of recovering tungsten-containing secondary waste in hydrometallurgy, and at the same time, it can solve the problem of filter residue accumulation and waste caused by hydrometallurgy.

[0030] 2) Low energy consumption and environmentally friendly: The smelting temperature of this invention is only 1600℃. If the raw materials are processed using traditional pyrometallurgy, the smelting temperature is about 1800℃ or higher. In addition, a large amount of waste is easily generated during the smelting process in the metallurgical industry. The products obtained by this invention are all harmless to the environment.

[0031] 3) Excellent performance: The high-entropy carbide alloy prepared by the method of this invention has a solid structure, and the problems of loose structure and pores are solved.

[0032] 4) High resource utilization: All products obtained by this invention can be further utilized. Among them, the high-entropy alloy material can be transferred to related fields due to its excellent performance, and the slag phase generated after melting contains silicate components, which can be further used to prepare microcrystalline glass.

[0033] 5) This invention can change the microstructure distribution of high-entropy carbides and binder phases in the alloy phase by controlling the directional solidification process, thereby achieving control over the alloy hardness. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 These are schematic diagrams of the melting and cross-sectional views of the products in Examples 1 and 3.

[0036] Figure 2 This is a bar graph showing the alloy recovery rates for Examples 1-3;

[0037] Figure 3 The hardness, electron microscopy, and EPMA analysis results of the product from Example 3 are shown below.

[0038] Figure 4 This is an electron microscope image of the product prepared in Example 5;

[0039] Figure 5 This is an electron microscope image of the product prepared in Example 7;

[0040] Figure 6 This is a schematic diagram of the present invention. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] This invention provides a method for preparing high-entropy carbides, comprising:

[0043] 1) Preparation of waste tungsten slag billets, the specific steps are as follows:

[0044] Waste tungsten slag (WO3 content: 5-10%, CoO content: 1-2%, Ta2O5 content: 4-7%, Nb2O5 content: 3-6%, Cr2O3 content: 1-5%, SiO2 content: 40-50%, TiO2 content: 10-25%) is mixed with copper converter slag (CuO content: 15-35%, Fe2O3 content: 15-30%, NiO2 content: 10-25%, CaO content: 25-30%, Al2O3 content: 10-20%, SiO2 content: 5-15%) and carbon powder at a mass ratio of 1:(0.6-1.0):(0.06-0.08) until homogeneous.

[0045] The uniformly mixed sample is formed into a columnar blank by cold isostatic pressing, with a diameter slightly smaller than the inner diameter of the crucible by 3-4 mm. The maximum pressure of cold isostatic pressing is 200 MPa, and the holding time at the maximum pressure is 3 min.

[0046] 2) High-frequency induction melting, the specific steps are as follows:

[0047] First, place the blank in the crucible. The initial sample occupies about 2 / 3 of the crucible volume. Inert gas is introduced into the furnace and the heating current is increased to raise the furnace temperature to 1600±20℃ at 20℃ / min, so that the sample is completely melted. At this time, the melt level drops to 1 / 3 of the crucible height.

[0048] Secondly, the billet is added to the melt through multiple feedings, increasing the volume of the melt to 4 / 5 of the crucible volume; finally, the melt is held at 1600℃ for 2 hours to obtain a stable melt.

[0049] 3) Directional solidification, the specific steps are as follows:

[0050] The bottom of the crucible is flush with the bottom of the induction coil (in the following embodiments, a VIF-2 vacuum induction melting furnace with a power of 25KW is used). The position of the induction coil is fixed, and the crucible is lowered 50mm at a speed of 1mm / min, then lowered again at a speed of 5mm / min until the top of the crucible is 20mm below the induction coil. This process is repeated multiple times to obtain a composite rich in high-entropy carbides and a binder phase. The high-entropy carbides are mainly composed of (W, Ta, Nb, Ti, Cr)C; the binder phase is mainly composed of Fe, Co, and Ni.

[0051] See attached document Figure 6As shown, in this invention, the raw materials are completely melted after smelting. The high-melting-point carbide phase and the binder phase are eutecticly melted into a liquid state, enriched in the lower part of the crucible, and separated from the slag phase. The crucible is moved downwards, moving the bottom away from the heat source, and the temperature decreases. At this point, the high-melting-point carbide phase (high-entropy carbide phase) gradually solidifies from the eutectic liquid state into a solid phase, enriching and depositing at the bottom of the crucible, because the system temperature no longer meets its melting point requirements. The low-melting-point binder phase remains in a liquid state and is enriched on top of the high-entropy carbide. Heating is then stopped, and the low-melting-point phase cools with the furnace into a solid phase, depositing on the carbides, resulting in a two-phase layered alloy ingot. Furthermore, to control the volume fraction of the binder phase in the high-entropy carbide composite and effectively improve the hardness of the final product, repeated directional solidification is performed multiple times, ultimately obtaining a composite rich in high-entropy carbides and the binder phase.

[0052] Example 1

[0053] The method for preparing high-entropy carbides provided in this embodiment includes the following steps:

[0054] Step 1) Preparation of waste tungsten slag billet, as detailed below:

[0055] Mix 30 kg of waste tungsten slag (WO3 content: 5-10%, CoO content: 1-2%, Ta2O5 content: 4-7%, Nb2O5 content: 3-6%, Cr2O3 content: 1-5%, SiO2 content: 40-50%, TiO2 content: 10-25%) with 1.8 kg of carbon powder evenly.

[0056] The uniformly mixed sample is formed into a columnar blank by cold isostatic pressing, with a diameter slightly smaller than the inner diameter of the crucible by 3-4 mm. The maximum pressure of cold isostatic pressing is 200 MPa, and the holding time at the maximum pressure is 3 min.

[0057] Step 2) High-frequency induction melting, as follows:

[0058] First, place the blank in the crucible. The initial sample occupies about 2 / 3 of the crucible volume. Argon gas is introduced into the furnace and the heating current is increased to raise the furnace temperature to 1600±20℃ at 20℃ / min, so that the sample is completely melted. At this time, the melt level drops to 1 / 3 of the crucible height.

[0059] Secondly, the billet is added to the melt through multiple feedings, increasing the volume of the melt to 4 / 5 of the crucible volume; finally, it is held at 1600℃ for 2 hours to obtain the product (high-entropy carbide).

[0060] Example 2

[0061] The preparation method of high-entropy carbides provided in this embodiment is basically the same as that in Example 1. The only difference is that in step 1) of this embodiment, 30 kg of waste tungsten slag, 18 kg of copper converter slag (CuO content: 15-35%, Fe2O3 content: 15-30%, NiO2 content: 10-25%, CaO content: 25-30%, Al2O3 content: 10-20%, SiO2 content: 5-15%), and 1.8 kg of carbon powder are mixed evenly.

[0062] Example 3

[0063] The preparation method of high-entropy carbides provided in this embodiment is basically the same as that in Example 2, except that the amount of copper converter slag added in this embodiment is 30 kg.

[0064] Example 4

[0065] The preparation method of high-entropy carbides provided in this embodiment is basically the same as that in embodiment 1. The only difference is that in step 1) of this embodiment, 10 kg of waste tungsten slag is mixed evenly with 8 kg of copper converter slag and 0.7 kg of carbon powder.

[0066] Example 5

[0067] The method for preparing high-entropy carbides provided in this embodiment includes the following steps:

[0068] Step 1) Preparation of waste tungsten slag billet, as detailed below:

[0069] Mix 10 kg of waste tungsten slag (WO3 content: 5-10%, CoO content: 1-2%, Ta2O5 content: 4-7%, Nb2O5 content: 3-6%, Cr2O3 content: 1-5%, SiO2 content: 40-50%, TiO2 content: 10-25%) with 8 kg of copper converter slag (CuO content: 15-35%, Fe2O3 content: 15-30%, NiO2 content: 10-25%, CaO content: 25-30%, Al2O3 content: 10-20%, SiO2 content: 5-15%) and 0.8 kg of carbon powder evenly.

[0070] The uniformly mixed sample is formed into a columnar blank by cold isostatic pressing, with a diameter slightly smaller than the inner diameter of the crucible by 3-4 mm. The maximum pressure of cold isostatic pressing is 200 MPa, and the holding time at the maximum pressure is 3 min.

[0071] Step 2) High-frequency induction melting, as follows:

[0072] First, place the blank in the crucible. The initial sample occupies about 2 / 3 of the crucible volume. Argon gas is introduced into the furnace and the heating current is increased to raise the furnace temperature to 1600±20℃ at 20℃ / min, so that the sample is completely melted. At this time, the melt level drops to 1 / 3 of the crucible height.

[0073] Secondly, the billet is added to the melt through multiple feedings, increasing the volume of the melt to 4 / 5 of the crucible volume; finally, the melt is held at 1600℃ for 2 hours to obtain a stable melt.

[0074] Step 3) Directional solidification, as follows:

[0075] The bottom of the crucible is flush with the bottom of the induction coil (the power of the induction coil is 25KW). The position of the induction coil is fixed. The crucible is dropped 50mm at a speed of 1mm / min and then dropped 5mm / min until the top of the crucible is 20mm below the induction coil, thus obtaining the product (a composite rich in high-entropy carbides and binder phase).

[0076] Example 6

[0077] The preparation method of high-entropy carbides provided in this embodiment is basically the same as that in embodiment 5. The only difference is that in step 1) of this embodiment, 30 kg of waste tungsten slag is mixed evenly with 27 kg of copper converter slag and 2.4 kg of carbon powder.

[0078] Example 7

[0079] The method for preparing high-entropy carbides provided in this embodiment includes the following steps:

[0080] Step 1) Preparation of waste tungsten slag billet, as detailed below:

[0081] Mix 30 kg of waste tungsten slag (WO3 content: 5-10%, CoO content: 1-2%, Ta2O5 content: 4-7%, Nb2O5 content: 3-6%, Cr2O3 content: 1-5%, SiO2 content: 40-50%, TiO2 content: 10-25%) with 27 kg of copper converter slag (CuO content: 15-35%, Fe2O3 content: 15-30%, NiO2 content: 10-25%, CaO content: 25-30%, Al2O3 content: 10-20%, SiO2 content: 5-15%) and 2.4 kg of carbon powder evenly.

[0082] The uniformly mixed sample is formed into a columnar blank by cold isostatic pressing, with a diameter slightly smaller than the inner diameter of the crucible by 3-4 mm. The maximum pressure of cold isostatic pressing is 200 MPa, and the holding time at the maximum pressure is 3 min.

[0083] Step 2) High-frequency induction melting, as follows:

[0084] First, place the blank in the crucible. The initial sample occupies about 2 / 3 of the crucible volume. Argon gas is introduced into the furnace and the heating current is increased to raise the furnace temperature to 1600±20℃ at 20℃ / min, so that the sample is completely melted. At this time, the melt level drops to 1 / 3 of the crucible height.

[0085] Secondly, the billet is added to the melt through multiple feedings, increasing the volume of the melt to 4 / 5 of the crucible volume; finally, the melt is held at 1600℃ for 2 hours to obtain a stable melt.

[0086] Step 3) Directional solidification, as follows:

[0087] The bottom of the crucible is flush with the bottom of the induction coil (the induction coil has a power of 25KW). The position of the induction coil is fixed. The crucible is lowered 50mm at a speed of 1mm / min, and then lowered again at a speed of 5mm / min until the top of the crucible is 20mm below the induction coil. This cycle is repeated 3 times to obtain the product (a composite rich in high-entropy carbides and a binder phase).

[0088] Example 8

[0089] The preparation method of high-entropy carbides provided in this embodiment is basically the same as that in Example 7, except that the number of cycles in step 3) of this embodiment is 4.

[0090] Example 9

[0091] The method for preparing high-entropy carbides provided in this embodiment is basically the same as that in Example 7, except that the number of cycles in step 3) of this embodiment is 5.

[0092] Product inspection and performance testing

[0093] The products obtained in Examples 1-9 were tested and their performance was evaluated. The results are as follows:

[0094] See attached document Figure 1 As shown in the left figure, it can be seen that adding copper converter slag can lower the temperature of the smelting system; as shown in the right figure, adding copper converter slag can promote the separation of the slag phase and the metal phase.

[0095] See attached document Figure 2 As shown in the figure, it can be seen that with the increase of copper converter slag addition, the recovery rate of rare and valuable metals (W, Co, Ta, Nb) also increases.

[0096] See attached document Figure 3 As shown in the figure, the obtained alloy has a good microstructure distribution of high-entropy carbide-binder phase, but due to the excessive volume fraction of binder phase, the overall hardness is low (average hardness value is 78.4 HRA).

[0097] See attached document Figure 4 As shown in the figure, directional solidification allows more high-entropy carbides to deposit at the bottom of the alloy, reducing the volume fraction of the binder phase in the high-entropy carbide composite.

[0098] Rockwell hardness tests were performed on the products obtained in Examples 4 and 5. The average hardness value of the product obtained in Example 4 was 76.8 HRA, and the average hardness value of the product obtained in Example 5 was 82.3 HRA, which showed an improvement in hardness compared with that before directional solidification.

[0099] See attached document Figure 5 As shown in the figure, more high-entropy alloys are deposited at the bottom of the alloy after three directional solidifications, and better slag-gold separation is achieved after three directional solidifications.

[0100] ICP-OES testing revealed that after one directional solidification, the alloy contained 17% W, 20% Co, 10% Ta, and 7% Nb. However, due to slightly poor slag-metal separation, the overall recovery rate of rare and valuable metals from the waste tungsten slag was only 88%. The alloy obtained after three directional solidifications had an overall recovery rate of 95% for valuable metals.

[0101] Rockwell hardness tests were performed on the products obtained in Examples 6 and 7; the average hardness value of the product obtained in Example 6 was 83.6 HRA, and the average hardness value of the product obtained in Example 7 was 89.3 HRA, which is an improvement over the first solidification hardness.

[0102] ICP-OES tests on the products obtained in Examples 8 and 9 revealed that after four directional solidifications, the overall recovery rate of valuable metals was 95%; after five directional solidifications, the overall recovery rate was 96%. The recovery rates of Examples 8 and 9 showed no significant improvement compared to Example 7. This is mainly because after three directional solidifications, the slag-metal separation was essentially complete, therefore, further increasing the number of directional solidifications did not significantly change the recovery rate of valuable metals.

[0103] The products obtained in Examples 8 and 9 were subjected to Rockwell hardness testing; the average hardness value of the product obtained in Example 8 was 89.0 HRA, and the average hardness value of the product obtained in Example 9 was 89.1 HRA. Compared with Example 7, the average hardness of Examples 8 to 9 showed no significant change. Therefore, in this invention, the preferred number of directional solidification cycles is 3.

[0104] The alloy obtained after melting in this invention contains high-entropy carbides and a binder phase. The high-entropy carbides are mainly composed of (W, Ta, Nb, Ti, Cr)C, with each main element accounting for 5-30%. The binder phase is mainly composed of Fe, Co, and Ni, with each element accounting for 20-50%. The high-entropy carbides are characterized by high melting point, high hardness, and high specific gravity. The binder phase promotes the formation of a dense body from the high-entropy carbides, improving the material's toughness, and has a low specific gravity. The volume fraction of the binder phase has a significant impact on the final overall hardness of the product. Directional solidification can alter the distribution of high-entropy carbides and the binder phase in the product, thereby achieving a product with superior performance.

[0105] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing high-entropy carbides, characterized in that, Includes the following steps: S1: Mix waste tungsten slag with copper converter slag and carbon powder at a mass ratio of 1:(0.6~1.0):(0.06~0.08) until homogeneous; S2: The uniformly mixed sample is formed into a columnar blank by cold isostatic pressing; S3: Place the billet in a crucible and heat it in an inert atmosphere until the sample is completely melted. The melt level drops to 1 / 3 of the crucible height. Add the billet into the melt multiple times to increase the melt volume to 4 / 5 of the crucible volume. Then perform isothermal treatment to obtain a stable melt. S4: Align the bottom of the crucible with the bottom of the induction coil and move it downwards to a preset height, specifically including the following steps: The bottom of the crucible is flush with the bottom of the induction coil. The crucible is lowered 50 mm at a speed of 1 mm / min and then lowered again at a speed of 5 mm / min until the top of the crucible is 20 mm below the induction coil. This process is repeated 3 times to obtain a composite rich in high-entropy carbides.

2. The method for preparing a high-entropy carbide according to claim 1, characterized in that, The waste tungsten slag contains 5~10% WO3, 1~2% CoO, 4~7% Ta2O5, 3~6% Nb2O5, 1~5% Cr2O3, 40~50% SiO2, and 10~25% TiO2.

3. The method for preparing a high-entropy carbide according to claim 1, characterized in that, The copper converter slag contains 15-35% CuO, 15-30% Fe2O3, 10-25% NiO2, 25-30% CaO, 10-20% Al2O3, and 5-15% SiO2.

4. The method for preparing a high-entropy carbide according to claim 1, characterized in that, The maximum pressure of the S2 isostatic cooling system is 200 MPa, and the holding time at the maximum pressure is 3 min.

5. The method for preparing a high-entropy carbide according to claim 1, characterized in that, The diameter of the columnar blank is 3-4 mm smaller than the inner diameter of the crucible.

6. The method for preparing a high-entropy carbide according to claim 1, characterized in that, The power of the induction coil is 25kW.

7. The method for preparing a high-entropy carbide according to claim 1, characterized in that, In S3, the temperature is increased at a rate of 20℃ / min to 1600±20℃ until the sample is completely melted.

8. The method for preparing a high-entropy carbide according to claim 1, characterized in that, The constant temperature in S3 is 1600℃, and the constant temperature time is 2 hours.

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