High-entropy alloy powder containing strong corrosion-resistant elements and a preparation method thereof

Abstract

This invention relates to a high-entropy alloy powder containing highly corrosion-resistant elements and its preparation method. The chemical atomic formula of the powder is Al. 17 Ni 17 Zr 17 Ti 17 Y 16 X 16 (X = Cr, Co, V). Preparation method: The raw materials are cleaned and dried, and all raw materials are subjected to multiple arc melting processes in a vacuum arc melting furnace according to the specified ratio to obtain a master alloy rod; then, the master alloy rod is atomized by a plasma rotating electrode to obtain a high-entropy alloy powder composed of highly corrosion-resistant elements. Advantages of this invention: The high-entropy alloy powder prepared by this invention has high sphericity and low oxygen content, and can be used as a raw material in industries such as laser cladding and cold / hot spraying. It can simultaneously take into account mechanical properties and meet the corrosion resistance requirements of large equipment in marine corrosive environments; the alloy components selected in this invention are moderately priced, and its preparation method is simple and easy to implement, making it suitable as a new type of corrosion-resistant surface protection material.

Description

Technical Field

[0001] This invention relates to the field of powder metallurgy, specifically to high-entropy alloy powder composed of multiple highly corrosion-resistant elements and its preparation method. Background Technology

[0002] High-entropy alloys are a new type of alloy composed of five or more elements in equiatomic or near-equiatomic ratios, with each atom comprising 5% to 35% (atomic percentage, at.%) of the alloy composition. This type of alloy was proposed in the 1990s based on research and development of bulk amorphous alloys. Because it is composed of multiple elements, each in a specific proportion, the alloy often exhibits four major effects: the thermodynamic high-entropy effect, the structural lattice distortion effect, the kinetic hysteresis diffusion effect, and the performance cocktail effect. These four effects result in a variety of excellent properties, such as high strength, high hardness, high wear resistance, strong corrosion resistance, and good magnetic properties, making it promising for applications in many fields.

[0003] Compared with conventional crystalline metal materials, amorphous alloys exhibit topological disorder from an atomic perspective, and their structure lacks defects such as grain boundaries, dislocations, and stacking faults. As a result, they possess outstanding characteristics such as extremely high strength, hardness, wear resistance, and corrosion resistance. Furthermore, they exhibit excellent superconductivity and low magnetic loss, making them promising for a wide range of applications in industries such as aerospace, chemical energy, and precision machinery.

[0004] Marine engineering equipment is the foundation of marine economic development, and the development of advanced marine engineering equipment has become a key area of ​​marine development. The marine environment is characterized by high temperature, high salinity, strong radiation, and strong seawater corrosiveness; however, marine engineering equipment, especially major offshore operational equipment (such as large ships), faces the challenge of long-term protection against corrosion, wear, erosion, biofouling, and the combined effects of these factors. Therefore, developing protective coating materials that balance the mechanical properties of structural materials with strong corrosion resistance is a milestone for the long-term protection of marine engineering equipment. To address the current gap in corrosion-resistant amorphous alloys for marine engineering, this invention improves the corrosion resistance of high-entropy amorphous alloys by adding highly corrosion-resistant elements and applies this improvement to coating preparation.

[0005] Plasma rotating electrode atomization is one method for producing spherical metal powders. In this method, elements or alloys are melted into alloy rods in a crucible according to a certain composition ratio. These rods are then heated and melted by a plasma gun, and atomized by centrifugal force to form spherical alloy powders. Compared to mechanical ball milling (e.g., patent CN108193146B), this invention provides a more efficient method that produces alloy powders suitable for large-scale production, meeting current needs. It avoids the drawbacks of mechanical alloying, such as non-spherical powders, insufficient compositional homogeneity, and the inability to produce amorphous powders. Summary of the Invention

[0006] The purpose of this invention is to provide a high-entropy alloy powder containing highly corrosion-resistant elements and its gas atomization preparation method. A novel design method for corrosion-resistant high-entropy alloy powder is explored, providing a new direction for the design of high-entropy alloys. Simultaneously, a plasma rotating electrode atomization method is used to prepare spherical powders with high amorphous content. This process has a high cooling rate, overcoming the deficiency of insufficient amorphous content in general gas atomization powder preparation.

[0007] The objective of this invention is achieved through the following methods.

[0008] This invention provides a high-entropy alloy powder containing elements with strong corrosion resistance. The specific content of each element in the alloy powder is as follows: Al 17 at.%, Ni 17 at.%, Zr 17 at.%, Ti 17 at.%, Y 16 at.% and X 16 at.%, X = Cr, Co, V, one of them.

[0009] The high-entropy alloy powder is spherical with a particle size of 15 μm to 53 μm.

[0010] This invention also provides a method for preparing the above-mentioned high-entropy alloy powder by plasma rotating electrode atomization. Specifically, it includes: cleaning and drying the raw materials, and then performing multiple arc melting operations on all the raw materials in a vacuum arc melting furnace according to the specified ratio to obtain a master alloy rod; subsequently, the master alloy rod is subjected to plasma rotating electrode atomization to obtain high-entropy alloy powder composed of highly corrosion-resistant elements.

[0011] Furthermore, when adding the Al, Ni, Zr, Ti, Y and X elements (X = Cr, Co, V), the temperature of the initial molten liquid is controlled below 1900℃, while ensuring that all elements constituting the master alloy are completely molten.

[0012] Furthermore, the diameter of the master alloy rod is 30mm~50mm, the length is 160mm~200mm, the surface roughness is ≤1μm, the roundness deviation is ≤0.05mm, the straightness deviation is ≤0.01mm, and the relative density is ≥99%.

[0013] Furthermore, the master alloy rod is placed in a plasma rotating electrode atomizing powder-making device, sealed, vacuumed, and a protective gas is introduced. The master alloy rod is then heated by a plasma gun to melt it uniformly. At the same time, the centrifugal force generated by the rotation of the rod causes the molten alloy droplets to be thrown out. The resulting granular powder is dried and sieved in the protective gas to obtain the powder.

[0014] Furthermore, during the plasma rotating electrode atomization preparation process, the oxygen content in the environment after the protective gas is introduced is <0.1wt%.

[0015] Furthermore, in the plasma rotating electrode atomization process, the distance between the master alloy rod and the plasma gun is 10 mm, the feed speed is 1.2 mm / s, the rotation speed is 30,000 r / min ~ 40,000 r / min, and the plasma working gas flow rate is 120 m³ / min. 3 / h.

[0016] After cooling the alloy powder obtained by atomization, collect and sieve it to obtain alloy powder with a particle size distribution of 15μm~53μm, and dry it to obtain high-entropy alloy powder material.

[0017] Preferably, the inert gas used is argon, with an argon pressure of 20 kg to 45 kg.

[0018] The present invention also provides the use of the high-entropy alloy powder material that combines mechanical properties and long-term corrosion resistance, using the alloy powder material as a coating for preparing corrosion-resistant and wear-resistant metal components in extreme marine environments.

[0019] The beneficial effects of this invention are as follows: the high-entropy alloy powder and its preparation method of this invention have the following beneficial effects: ① This invention is based on the design concept of multi-component alloys. On the one hand, by using large-sized atomic Y elements that can promote amorphous formation, the alloy material can simultaneously satisfy the high entropy effect under thermodynamic conditions and also have the potential to form amorphous structures. On the other hand, the addition of strong corrosion-resistant elements such as Al, Ni, Cr, Co, and V will lead to an improvement in the corrosion resistance of the alloy. Therefore, this invention adjusts and optimizes the selection of elements to make the high-entropy alloy more inclined to present an amorphous structure while taking into account both the mechanical properties and corrosion resistance of the material, thereby further improving the performance of the alloy.

[0020] ②The high-entropy alloy powder preparation method of the present invention, compared with the conventional ball milling method and planetary ball milling method, the powder preparation method of the present invention for preparing near-equal atomic ratio AlNiZrTiYX (X = Cr, Co, V) alloy powder has a simple process, high production efficiency, and the high-entropy alloy powder obtained has high sphericity and oxygen content of less than 500 ppm. It can be used as a raw material for industries such as 3D laser cladding and cold / hot spraying.

[0021] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention.

[0022] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0023] This invention has a total of 8 accompanying drawings. Figure 8 The attached figure is for the abstract.

[0024] Figure 1 . are the XRD patterns of the three high-entropy alloy powders containing highly corrosion-resistant elements of the present invention; Figure 2 This is Al from Embodiment 1 of the present invention. 17 Ni 17 Zr 17 Ti 17 Y 16 Cr 16 SEM image of alloy powder; Figure 3 This is Al in Embodiment 2 of the present invention. 17 Ni 17 Zr 17 Ti 17 Y 16 Co 16 SEM image of alloy powder; Figure 4 This is Al in Embodiment 3 of the present invention. 17 Ni 17 Zr 17 Ti 17 Y 16 V 16 SEM image of alloy powder; Figure 5 This is Al from Embodiment 1 of the present invention. 17 Ni 17 Zr 17 Ti 17 Y 16 Cr 16 SEM image of the alloy coating; Figure 6 This is Al in Embodiment 2 of the present invention. 17 Ni 17 Zr 17 Ti 17 Y 16 Co 16 SEM image of the alloy coating; Figure 7 This is Al in Embodiment 3 of the present invention. 17 Ni 17 Zr 17 Ti 17 Y 16 V 16 SEM image of the alloy coating; Figure 8 This is a flowchart of the preparation method of the present invention. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of the present invention, but not all embodiments.

[0026] Compared to other alloys, the alloy designed in this invention exhibits superior sphericity. Furthermore, because the alloy is composed of highly corrosion-resistant elements, coating materials prepared using this series of alloy powders are expected to possess even stronger corrosion resistance. Additionally, the plasma rotating electrode atomization method for preparing alloy powders offers a rapid cooling rate, reaching up to 10... 5 With a K / s or higher, it can maximize the formation of an amorphous structure.

[0027] To solve the above-mentioned technical problems, the present invention provides a high-entropy alloy powder comprising the following elements (atomic fraction): Al: 17 at.%, Ni: 17 at.%, Zr: 17 at.%, Ti: 17 at.%, Y: 16 at.% and X: 16 at.% (X = one of Cr, Co, V).

[0028] Specifically, the raw materials Al, Ni, Zr, Ti, Y, Cr, Co, and V used in the preparation of the ingots of this invention are all commercially available granular or blocky raw materials with a purity higher than 99 wt%.

[0029] This invention provides a method for preparing high-entropy alloy powder by plasma rotating electrode atomization, comprising cleaning and drying the raw materials, repeatedly vacuum arc melting all the constituent elements to obtain a master alloy rod, then performing plasma rotating electrode atomization on the high-entropy alloy ingot, and then taking out and sieving the atomized powder to obtain high-entropy alloy powder.

[0030] Optionally, during induction melting, the vacuum level of the equipment is less than 4.5 × 10⁻⁶. -3 Pa ~ 5.0 × 10 -3 Before melting, argon gas is introduced to 0.05 MPa, the induction heating power supply is started, and the heating power is adjusted (5-20 kW).

[0031] Optionally, the rod is subjected to plasma rotating electrode atomization to produce powder. The selected master alloy rod has a diameter of 30-50 mm, a length of 160-200 mm, a surface roughness of ≤1 μm, a roundness deviation of ≤0.05 mm, a straightness deviation of ≤0.01 mm, and a relative density of ≥99%.

[0032] Optionally, in the plasma rotating electrode atomization powder production process, the distance between the master alloy rod and the plasma gun is 10 mm, the feed speed is 1.2 mm / s, the rotation speed is 30,000-40,000 r / min, and the plasma working gas flow rate is 120 m³ / min. 3 / h.

[0033] Optionally, during the plasma rotating electrode atomization powder preparation process, the oxygen content in the environment after the protective gas is introduced is <0.1wt%, the plasma gun current is 800-1000A, and the voltage is 80V.

[0034] Optionally, the amorphousness of the high-entropy alloy powder is not less than 60%.

[0035] Optionally, the oxygen content of the high-entropy alloy powder does not exceed 500 ppm.

[0036] Optionally, the particle size of the high-entropy alloy powder is selected to be 15-53 μm.

[0037] Examples 1-3 below illustrate the preparation of Al 17 Ni 17 Zr 17 Ti 17 Y 16 Cr 16 Al 17 Ni 17 Zr 17 Ti 17 Y 16 Co 16 Al 17 Ni 17 Zr 17 Ti 17 Y 16 V 16 The alloy powder and thermal spray coating were studied, and their microstructures were characterized. The preparation method is as follows: Figure 8 As shown.

[0038] Example 1 1) Batching calculation based on atomic fraction: Al: 17 at.%; Ni: 17 at.%; Zr: 17 at.%; Ti: 17 at.%; Y: 16 at.%; Cr: 16 at.%. Raw material processing: Industrial materials (purity ≥ 99%) are used for batching. Before batching, the raw materials are pre-treated on the surface and then cleaned with alcohol using ultrasonic cleaning. Each batch is 3.5 kg. The cleaned raw materials are then dried in a vacuum drying oven at a temperature below 150℃ to prevent oxidation.

[0039] 2) Master alloy bar preparation process: Clean the inner wall and viewing window of the induction furnace with lint-free paper and alcohol. Place the raw materials together for arc melting, with Al at the bottom, Zr and Cr at the top, and the remaining elements in the middle. Perform a vacuum operation on the arc furnace to make the vacuum level of the equipment lower than 4.5×10. -3 Pa-5.0×10 -3 Pa, then perform gas washing, repeating 2-3 times. After gas washing, continue vacuuming. When the vacuum level is below 8 Pa, turn off the vacuum device and purge with low-pressure high-purity argon (purity: 99.99%) to -0.05 MPa as a protective gas and arc-ignition medium. Turn on the melting power supply and adjust the heating current to 200A-350A. Simultaneously, remelt 3-5 times to ensure the compositional uniformity of the alloy ingot. After cooling, obtain Al. 17 Ni 17 Zr 17 Ti 17 Y 16 Cr 16 Master alloy ingot. Master alloy bars of the required size are obtained through precision machining. The bars have a density of 99% and no obvious casting defects such as porosity. After machining, the bars have a diameter of 30 mm, a length of 200 mm, a surface roughness of 0.5 μm, a roundness deviation of 0.04 mm, and a straightness deviation of 0.01 mm.

[0040] 3) Plasma rotating electrode atomization powder production process: The master alloy rod to be atomized is loaded into the plasma rotating electrode atomization powder production device. The loading must strictly ensure that the rod's axis corresponds to the holding center to prevent rotational deflection. The distance between the master alloy rod and the plasma gun is 10mm. Then, a vacuum operation is performed. When the equipment vacuum degree is 3×10⁻⁶... -3 When the pressure reaches Pa, turn off the vacuum device and fill the chamber with high-purity argon gas until the pressure inside the chamber reaches 0.1 × 10⁻⁶. -3Pa, ensuring the oxygen content in the atmosphere is less than 0.1 wt%. Turn on the power, set the working voltage to 80V, the plasma gun current to 1000A, and the rod rotation speed to 40000 r / min. Use the plasma gun to heat the end face of the master alloy rod to make it melt uniformly, and rely on the centrifugal force generated by the rotation to throw the molten droplets out at high speed. The droplets are rapidly cooled in the inert gas environment to form spherical particles. The spherical powder particles are classified, collected, sieved, and vacuum-packed in the inert gas atmosphere, finally obtaining high-entropy alloy spherical powder such as... Figure 2 As shown, its powder particle size is 15μm~53μm, oxygen content is 470ppm, yield is 35%, and amorphous content is 66.1%. Figure 1 As shown.

[0041] 4) Plasma spraying coating preparation process: A 45 steel substrate is used. Before spraying, the substrate is cleaned and sandblasted. The spray gun current is 400A, the powder feed rate is 35g / min, the gun travel speed is 1000m / s, the spraying distance is 200mm, and the voltage is 65V. During spraying, 3-5 cycles are applied per coat. After spraying, the substrate should be cooled for approximately 30 seconds to prevent overheating. The coating thickness is measured periodically during spraying, and the increase in coating thickness per cycle is recorded. Figure 5 As shown, the final coating thickness should be 150μm~300μm.

[0042] Example 2 1) Batching calculation based on atomic fraction: Al, 17 at.%; Ni, 17 at.%; Zr, 17 at.%; Ti, 17 at.%; Y, 16 at.%; Co, 16 at.%. Raw material processing: Industrial materials (purity ≥99%) are used for batching. Before batching, the raw materials are pre-treated on the surface and then cleaned with alcohol using ultrasonic cleaning. Each batch is 3.5 kg. The cleaned raw materials are then dried in a vacuum drying oven at a temperature below 150℃ to prevent oxidation.

[0043] 2) Master alloy bar preparation process: Clean the inner wall and viewing window of the induction furnace with lint-free paper and alcohol. Place the raw materials together for arc melting, with Al at the bottom, Zr and Cr at the top, and the remaining elements in the middle. Perform a vacuum operation on the arc furnace to make the vacuum level of the equipment lower than 4.5×10. -3 Pa ~ 5.0 × 10 -3Pa, then perform gas washing, repeating 2-3 times. After gas washing, continue vacuuming. When the vacuum level is below 8 Pa, turn off the vacuum device and purge with low-pressure high-purity argon (purity: 99.99%) to -0.05 MPa as a protective gas and arc-ignition medium. Turn on the melting power supply and adjust the heating current to 200A-350A. Simultaneously, remelt 3-5 times to ensure the compositional uniformity of the alloy ingot. After cooling, obtain Al. 17 Ni 17 Zr 17 Ti 17 Y 16 Co 16 Master alloy ingot. Master alloy bars of the required size are obtained through precision machining. The bars have a density of 99.2% and no obvious casting defects such as porosity. The diameter of the machined bars is 40 mm, the length is 180 mm, the surface roughness is 1 μm, the roundness deviation is 0.05 mm, and the straightness deviation is 0.008 mm.

[0044] 3) Plasma rotating electrode atomization powder production process: The master alloy rod to be atomized is loaded into the plasma rotating electrode atomization powder production device. The loading must strictly ensure that the rod's axis corresponds to the holding center to prevent rotational deflection. The distance between the master alloy rod and the plasma gun is 10mm. Then, a vacuum operation is performed. When the equipment vacuum degree is 3×10⁻⁶... -3 When the pressure reaches Pa, turn off the vacuum device and fill the chamber with high-purity argon gas until the pressure inside the chamber reaches 0.1 × 10⁻⁶. -3 Pa, ensuring the oxygen content in the atmosphere is less than 0.1 wt%. Turn on the power, set the working voltage to 80V, the plasma gun current to 900A, and the rod rotation speed to 35000 r / min. Use the plasma gun to heat the end face of the master alloy rod to make it melt uniformly, and rely on the centrifugal force generated by the rotation to throw the molten droplets out at high speed. The droplets are rapidly cooled in the inert gas environment to form spherical particles. The spherical powder particles are classified, collected, sieved, and vacuum-packed in the inert gas atmosphere, finally obtaining high-entropy alloy spherical powder such as Figure 3 As shown, the powder particle size is 15μm~53μm, the oxygen content is 450ppm, the yield is 38%, and the amorphous content is 65.9%. Figure 1 ).

[0045] 4) Plasma spraying coating preparation process: A 45 steel substrate is used. Before spraying, the substrate is cleaned and sandblasted. The spray gun current is 550A, the powder feed rate is 35g / min, the gun travel speed is 750m / s, the spraying distance is 200mm, and the voltage is 65V. During spraying, 3-5 cycles are applied per coat. After spraying, the substrate should be cooled for approximately 30 seconds to prevent overheating. The coating thickness is measured periodically during spraying, and the increase in coating thickness per cycle is recorded. Figure 6As shown, the final coating thickness should be 150μm ~ 300μm.

[0046] Example 3 1) Batching calculation based on atomic fraction: Al, 17 at.%; Ni, 17 at.%; Zr, 17 at.%; Ti, 17 at.%; Y, 16 at.%; V, 16 at.%. Raw material processing: Industrial materials (purity ≥99%) are used for batching. Before batching, the raw materials are pre-treated on the surface and then cleaned with alcohol using ultrasonic cleaning. Each batch is 3.5 kg. The cleaned raw materials are then dried in a vacuum drying oven at a temperature below 150℃ to prevent oxidation.

[0047] 2) Master alloy bar preparation process: Clean the inner wall and viewing window of the induction furnace with lint-free paper and alcohol. Place the raw materials together for arc melting, with Al at the bottom, Zr and Cr at the top, and the remaining elements in the middle. Perform a vacuum operation on the arc furnace to make the vacuum level of the equipment lower than 4.5×10. -3 Pa ~ 5.0 × 10 -3 Pa, then perform gas washing, repeating 2-3 times. After gas washing, continue vacuuming. When the vacuum level is below 8 Pa, turn off the vacuum device and purge with low-pressure high-purity argon (purity: 99.99%) to -0.05 MPa as a protective gas and arc-ignition medium. Turn on the melting power supply and adjust the heating current to 200A-350A. Simultaneously, remelt 3-5 times to ensure the compositional uniformity of the alloy ingot. After cooling, obtain Al. 17 Ni 17 Zr 17 Ti 17 Y 16 V 16 Master alloy ingot. Master alloy bars of the required size are obtained through precision machining. The bars have a density of 99.1% and no obvious casting defects such as porosity. The diameter of the bars after machining is 50 mm, the length is 160 mm, the surface roughness is 1 μm, the roundness deviation is 0.05 mm, and the straightness deviation is 0.01 mm.

[0048] 3) Plasma rotating electrode atomization powder production process: The master alloy rod to be atomized is loaded into the plasma rotating electrode atomization powder production device. The loading must strictly ensure that the rod's axis corresponds to the holding center to prevent rotational deflection. The distance between the master alloy rod and the plasma gun is 10mm. Then, a vacuum operation is performed. When the equipment vacuum degree is 3×10... -3 When the pressure reaches Pa, turn off the vacuum device and fill the chamber with high-purity argon gas until the pressure inside the chamber reaches 0.1 × 10⁻⁶. -3Pa, ensuring the oxygen content in the atmosphere is less than 0.1 wt%. Turn on the power, set the working voltage to 80V, the plasma gun current to 900A, and the rod rotation speed to 30000 r / min. Use the plasma gun to heat the end face of the master alloy rod to make it melt uniformly, and rely on the centrifugal force generated by the rotation to throw the molten droplets out at high speed. The droplets are rapidly cooled in the inert gas environment to form spherical particles. The spherical powder particles are classified, collected, sieved, and vacuum-packed in the inert gas atmosphere, finally obtaining high-entropy alloy spherical powder, such as... Figure 4 As shown, the powder particle size is 15μm~53μm, the oxygen content is 420ppm, the yield is 32%, and the amorphous content is 65.7%. Figure 1 As shown.

[0049] 4) Plasma spraying coating preparation process: A 45 steel substrate is used. Before spraying, the substrate is cleaned and sandblasted. The spray gun current is 600A, the powder feed rate is 35g / min, the gun travel speed is 500m / s, the spraying distance is 150mm, and the voltage is 65V. During spraying, 3-5 cycles are applied per coat. After spraying, the substrate should be cooled for approximately 30 seconds to prevent overheating. The coating thickness is measured periodically during spraying, and the increase in coating thickness per cycle is recorded. Figure 7 As shown, the final coating thickness should be 150μm~300μm.

[0050] The high-entropy alloy powders prepared in each embodiment were subjected to relevant performance tests, and the data are summarized in Table 1.

[0051] Table 1 Performance data of the high-entropy amorphous alloy powders prepared in each embodiment.

[0052] Combined with Table 1 and Figures 1 to 7 It can be seen that the high-entropy alloy powder containing elements with strong corrosion resistance prepared by the gas atomization method of this invention has high sphericity and low oxygen content. The porosity of the prepared coating is less than 3%, which can be used as a raw material for laser cladding, cold / hot spraying and other industries.

[0053] In summary, the high-entropy alloy powder and its preparation method described in this invention only require commonly used high-entropy alloy powders with low to high amorphous content, and can be applied to surface protection fields such as laser cladding and cold / hot spraying. Arc melting and machining processes, along with plasma rotating electrode atomization, can directly produce powders with high sphericity and low oxygen content.

[0054] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A method for preparing high-entropy alloy powder containing highly corrosion-resistant elements, characterized in that, The method includes the following steps: 1) According to the alloy chemical formula Al 17 Ni 17 Zr 17 Ti 17 Y 16 X 16 Weigh out the required mass of Al, Ni, Zr, Ti, Y, and X granular or bulk raw materials and perform surface treatment, while considering the ablation of low-melting-point metals; X = Cr, Co, or V; Each batch of ingredients is 3.5 kg; 2) Melt the raw materials prepared in step 1) in a vacuum arc furnace using a melting current of 200A to 350A to produce master alloy bars. Perform a vacuum evacuation operation on the vacuum arc furnace, ensuring a vacuum level of 4.5 × 10⁻⁶. -3 Pa ~ 5.0 × 10 -3 Pa, repeatedly smelted 3 to 5 times; 3) Place the master alloy rod from step 2) into a plasma rotating electrode atomizing powder making device, seal it, vacuum it and introduce protective gas. There is a certain distance between the master alloy rod and the plasma gun. Then use the plasma gun to heat the master alloy rod so that it melts evenly. At the same time, rely on the centrifugal force generated by the rotation of the master alloy rod to throw out the molten alloy droplets. The resulting particulate powder is dried and sieved in the protective gas to obtain high entropy alloy powder containing strong corrosion-resistant elements. The amorphism of the high-entropy alloy powder is not less than 60%; the oxygen content of the high-entropy alloy powder does not exceed 500 ppm; the high-entropy alloy powder is spherical. In step 3), the distance between the master alloy rod and the plasma gun is 10 mm, the feed speed is 1.2 mm / s, the rotation speed is 30,000 r / min to 40,000 r / min, and the plasma working gas flow rate is 120 m³ / min. 3 / h; The plasma gun has a current of 800A to 1000A and a voltage of 80V. 4) The obtained high-entropy alloy powder containing elements with strong corrosion resistance is used to prepare a high-entropy amorphous alloy coating by plasma spraying.

2. The method for preparing a high-entropy alloy powder containing a highly corrosion-resistant element according to claim 1, characterized in that: The surface treatment in step 1) involves mechanically grinding the granular or bulk raw material to remove the surface oxide scale, followed by ultrasonic cleaning with acetone or alcohol for 30 seconds, and repeating the cleaning 1 to 3 times.

3. The method for preparing a high-entropy alloy powder containing a highly corrosion-resistant element according to claim 1, characterized in that: In step 2), the diameter of the master alloy rod is 30mm to 50mm, the length is 160mm to 200mm, the surface roughness is ≤1μm, the roundness deviation is ≤0.05mm, the straightness deviation is ≤0.01mm, and the relative density is ≥99%.

4. The method for preparing a high-entropy alloy powder containing a highly corrosion-resistant element according to claim 1, characterized in that: The particle size of the high-entropy alloy powder after sieving in step 3) is 15μm to 53μm.

5. The method for preparing a high-entropy alloy powder containing a highly corrosion-resistant element according to claim 1, characterized in that: The protective gas in step 3) is high-purity argon.

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