High-entropy amorphous coating material containing refractory particles as well as preparation method and application of high-entropy amorphous coating material

Abstract

The invention discloses a high-entropy amorphous coating material containing refractory particles as well as a preparation method and application of the high-entropy amorphous coating material. The preparation method comprises the following steps: (1) uniformly mixing metal and non-metal materials, smelting and crushing to obtain a high-entropy amorphous alloy material; (2) carrying out plasma atomization on the high-entropy amorphous alloy material, blowing refractory nano powder into high-entropy amorphous alloy liquid drops formed after atomization, cooling and screening out composite powder suitable for laser cladding; the melting point of the refractory nanopowder is higher than that of the high-entropy amorphous alloy material; and (3) the composite powder is loaded on a base body through laser cladding, and the high-entropy amorphous coating material containing the refractory particles is formed. Different from traditional mechanical mixing powder preparation, the plasma atomization technology is adopted for preparing the high-entropy amorphous alloy material mixed with the refractory nano powder, and the coating prepared through the laser cladding technology has the advantages of being high in hardness and high in amorphous content.

Description

Technical Field

[0001] This invention relates to the technical field of coating preparation, specifically to a high-entropy amorphous coating material containing refractory particles, its preparation method, and its application. Background Technology

[0002] With the development of marine resources and the rapid advancement of marine engineering technology, the durability and reliability of materials in extreme marine environments have become a research hotspot. Especially in fields such as deep-sea exploration, offshore oil platforms, wind turbines, and marine vessels, materials exposed to complex environments such as seawater, marine climate, and wave impacts over long periods often face severe abrasion problems. Abrasion not only affects the service life of materials but can also endanger equipment safety and lead to economic losses. Therefore, studying the abrasion performance of materials in extreme marine environments is particularly important.

[0003] High-entropy amorphous alloys have attracted widespread attention due to their high strength, hardness, and excellent wear and corrosion resistance. Laser cladding technology, with its high energy density, small heat-affected zone, and rapid cooling rate, is considered an effective method for preparing high-entropy amorphous alloy coatings. However, based on existing research reports and inventors' experimental practices, the amorphous content of iron-based amorphous coatings prepared by laser cladding is very low. This low amorphous content results in low hardness of the high-entropy amorphous coating, failing to meet service requirements. Moreover, as the service environment of marine equipment becomes increasingly harsh, the performance requirements for the surface of its components are also increasing, and the performance of existing high-entropy amorphous materials cannot meet the extremely demanding service conditions.

[0004] Laser cladding is an advanced surface modification technology. Its principle involves irradiating the surface of a metal substrate with a high-energy laser beam, simultaneously adding a material layer or pre-preparing a powder layer, which melts together with the substrate and then rapidly solidifies to form a metallurgically bonded layer, thereby improving the properties of the substrate. This technology features high metallurgical bonding strength, a good metallurgical bond between the substrate and the coating, precise controllability allowing for accurate melting of specific areas, low dilution rate, and a small heat-affected zone. Because laser cladding is localized and heating is precise, the heat input is relatively small, minimizing thermal deformation of the substrate. However, traditional mechanical mixing of multiple powders places high demands on coating preparation technology and the addition of elements. For example, adding refractory metals requires high laser power, results in poor surface formation, and leads to uneven internal structure of the coating.

[0005] For example, CN119020771A discloses a method for preparing a high-hardness coating of iron-based amorphous alloy with hybrid high-entropy alloys. This method utilizes laser cladding technology to prepare the high-entropy amorphous composite coating. However, due to the presence of high-melting-point metal elements such as Mo, higher laser power is required, and the large heat input leads to internal crystallization. Low amorphous content results in low hardness. Furthermore, mechanically mixing the two powders via ball milling can cause uneven internal structure in the prepared coating, resulting in certain defects.

[0006] Therefore, the performance of existing laser cladding high-entropy amorphous coatings is insufficient to meet the harsh service conditions and needs further improvement. Summary of the Invention

[0007] The purpose of this invention is to provide a high-entropy amorphous coating material containing refractory particles, its preparation method, and its application. This invention utilizes plasma atomization technology to manufacture high-entropy amorphous alloy materials. During the atomization process, a certain amount of refractory nanoparticles (Mo, Re, etc.) are added, fusing the powder with the unsolidified high-entropy amorphous metal droplets. Because the melting points of Mo, Re, and other powders are much higher than those of the high-entropy amorphous material, they essentially do not melt when incorporated into the high-entropy amorphous droplets. The high-melting-point nanoparticles produced by atomization cooling then reinforce the high-entropy amorphous alloy composite powder. At this point, each high-entropy amorphous spherical powder contains a certain number of Mo and Re particles. Using this composite powder for laser cladding ensures that the high-entropy amorphous powder does not completely melt during the melting of the nanoparticles. The unmelted portion increases the nucleation rate of the high-entropy amorphous material, promoting grain refinement. Furthermore, these refractory metal nanoparticles are dispersed throughout the coating, avoiding agglomeration problems that occur with traditional mixing methods, thus achieving dispersion strengthening. Furthermore, the molten portion of the refractory nanoparticles can effectively promote the formation of more amorphous structures in the coating (because Mo and Re can promote the formation of amorphous phases). In summary, this method can be used to prepare high-quality coatings that meet harsh service conditions.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] The first aspect of this invention is to provide a method for preparing a high-entropy amorphous coating material containing refractory particles, comprising the following steps:

[0010] (1) After mixing the metal and non-metal materials evenly, melt and crush them to obtain a high-entropy amorphous alloy material;

[0011] (2) The high-entropy amorphous alloy material is plasma-atomized, and refractory nanoparticles are blown into the high-entropy amorphous alloy droplets formed after atomization. The mixture is then cooled and sieved to obtain composite powder suitable for laser cladding. The melting point of the refractory nanoparticles is greater than that of the high-entropy amorphous alloy material.

[0012] (3) The composite powder is loaded onto the substrate by laser cladding to form a high-entropy amorphous coating material containing refractory particles.

[0013] As a preferred implementation method,

[0014] Step (1),

[0015] The metal is selected from at least one of Fe, Co, Ni, Cr, Mn, Al, Ti, or Cu; and / or,

[0016] The non-metallic material is selected from at least one of B, Si, P, or C; and / or,

[0017] The melting is carried out using a vacuum induction melting furnace or an electric arc melting furnace under a protective atmosphere.

[0018] As a preferred implementation method,

[0019] Step (1),

[0020] First, the composition of the high-entropy amorphous alloy is designed by selecting five or more main metals (such as Fe, Co, Ni, Cr, Mn, Al, Ti, Cu, etc.), which must satisfy the requirement of high mixing entropy (Δ). S ≥ 1.5R, where R is the gas constant), and then optimize the amorphous forming ability by adding non-metallic elements (such as B, Si, P, C) to improve glass-forming ability (GFA). This is achieved through the enthalpy of mixing (Δ). H ), atomic size difference (δ) and mixing entropy (Δ) S A series of thermodynamic calculations were performed to evaluate the amorphous forming ability, and the following raw material composition was ultimately selected for preparing high-entropy amorphous alloy materials: In the high-entropy amorphous alloy materials, based on the total mass of metal and non-metal raw materials as 100%, the addition amount of Co is 10wt%-20wt%, the addition amount of Cr is 10wt%-20wt%, the addition amount of Fe is 20wt%-30wt%; the addition amount of Ni is 10wt%-20wt%, the addition amount of B is 5wt%-10wt%, the addition amount of Si is 10wt%-15wt%, and the addition amount of C is 5wt%-10wt%; or,

[0021] In high-entropy amorphous alloy materials, based on the total mass of metallic and non-metallic raw materials as 100%, the following amounts are added: Al 10-20 wt%, Co 5-15 wt%, Cr 10-20 wt%, Fe 20-30 wt%, Ni 10-20 wt%, B 5-15 wt%, and Si 5-15 wt%.

[0022] The melting temperature is 1500-1700℃; and / or,

[0023] The melting is carried out in a vacuum induction melting furnace with a vacuum degree ≤10. -3 Pa; and / or,

[0024] During the aforementioned smelting process, each smelting session lasts 15-45 minutes; and / or,

[0025] The melting process is repeated 3-5 times; and / or,

[0026] After being pulverized, the particle size of the high-entropy amorphous alloy material is 1-5 mm.

[0027] As a preferred implementation method,

[0028] Step (2),

[0029] During plasma atomization, the plasma atomization temperature is 10000-20000 K; and / or,

[0030] During plasma atomization, the feed rate of the high-entropy amorphous alloy material is 0.5-2 kg / h; and / or,

[0031] The gas used during plasma atomization is a protective gas, and the flow rate of the protective gas is 50-100 L / min; and / or,

[0032] The atomization pressure during plasma atomization is 2-10 MPa; preferably 5-8 MPa.

[0033] As a preferred implementation method,

[0034] Step (2),

[0035] The refractory nanopowder is selected from at least one of Mo, Re, Y₂O₃, and La₂O₃; and / or,

[0036] The refractory nanoparticles have a particle size of 100-200 nm; and / or,

[0037] A side powder feeding pipe is added to the plasma atomization chamber, and a protective gas of the same type as that used in plasma atomization is used for protection. Refractory nanopowder is blown into high-entropy amorphous alloy droplets through the side powder feeding pipe. The powder feeding rate of the refractory nanopowder is 15-25 g / min. The side powder feeding pipe is located on the left side of the plasma atomization main equipment cavity (i.e., the equipment cavity where the plasma atomization chamber is located). The nozzle of the side powder feeding pipe is located in the atomization cooling zone downstream of the axial position of the main nozzle of the plasma atomization equipment (i.e., the outlet of the high-entropy amorphous alloy material). The vertical distance between the nozzle of the side powder feeding pipe and the main nozzle of the plasma atomization equipment is 50mm-200mm.

[0038] The side powder feeding pipe should be tilted downwards, and the angle between the axis of the side powder feeding pipe and the axis of the main nozzle of the plasma atomizing equipment (the direction of metal droplet flight) should be set between 30° and 45°.

[0039] The radial distance between the side powder delivery pipe inlet and the bottom surface of the main nozzle of the plasma atomizing equipment is 5 mm to 15 mm.

[0040] The inner diameter of the side powder delivery pipe nozzle is set between 1mm and 3mm; and / or,

[0041] Composite powders of different particle sizes are cooled and separated using a cyclone separator in an inert gas environment; and composite powders suitable for laser cladding are then sieved out, with a particle size of 30-60µm; the preferred cooling rate is 10. 5 -10 6 K / s.

[0042] The vertical distance between the nozzle of the aforementioned side powder delivery pipe and the main nozzle of the plasma atomizing equipment is too close (<50mm): the droplet temperature is too high, it is completely liquid, and the nanoparticles are difficult to capture (wetting problem), and the powder delivery pipe itself is at risk of being burned by high temperature radiation.

[0043] The vertical distance between the nozzle of the aforementioned side powder feeding pipe and the main nozzle of the plasma atomizing equipment is too far (>200mm): the droplets may have cooled and solidified into solid powder, and the nanoparticles can only mechanically adhere to the powder surface, failing to achieve internal metallurgical bonding, and are prone to falling off in subsequent processing.

[0044] The optimal position is when the metal droplet is in the solid-liquid two-phase region. At this time, a thin solid shell has formed on the surface of the droplet, while the inside is still liquid. After the nanoparticles collide, they can be "frozen" on the surface or embedded inside.

[0045] If the angle between the axis of the aforementioned side powder delivery pipe and the axis of the main nozzle of the plasma atomizing device is too small (e.g., <30°), the nano airflow is almost parallel to the main airflow, the relative velocity is low, the interaction is weak, and the particles may not be able to effectively penetrate the droplet flow.

[0046] If the angle between the axis of the aforementioned side powder feeding pipe and the axis of the main nozzle of the plasma atomization equipment is too large (e.g., >45°), the nano airflow will cause strong disturbance to the metal droplet flow, which may affect the sphericity of the powder and even cause droplet splashing.

[0047] The powder delivery pipe nozzle should not be directly attached to the metal droplet stream; a certain distance should be maintained to allow the carrier gas flow to disperse and evenly envelop the metal droplet stream. The radial distance between the side branch powder delivery pipe inlet and the bottom surface of the main nozzle of the plasma atomization equipment should be 5 mm to 15 mm.

[0048] The side powder delivery pipe uses 316 stainless steel, while the high-temperature area (nozzle) uses Inconel 600 nickel-based high-temperature alloy.

[0049] As a preferred implementation method,

[0050] Step (3),

[0051] The substrate is a marine steel substrate, specifically E690 marine steel; and / or,

[0052] The distance between the laser head nozzle and the substrate in the laser cladding process is set to 14-25 mm; and / or,

[0053] The angle between the laser head of the laser cladding and the horizontal plane of the substrate is 75°-85°.

[0054] As a preferred implementation method,

[0055] Step (3),

[0056] The powder feeding rate for laser cladding is set to 15-25 g / min; and / or,

[0057] During the laser cladding process, the scanning speed of the laser head is 15mm / s-20mm / s; and / or,

[0058] The laser used for laser cladding is a laser with a wavelength of 1000-1100 nm; and / or,

[0059] During laser cladding, the laser power is 1400-1900W.

[0060] A second aspect of the present invention is to provide a high-entropy amorphous coating material containing refractory particles prepared by the method described in the first aspect of the present invention.

[0061] As a preferred implementation method,

[0062] The amorphous content of the high-entropy amorphous coating material containing refractory particles is 40-60 wt%;

[0063] The hardness of the high-entropy amorphous coating material containing refractory particles is 1000-1300HV;

[0064] The wear rate of the high-entropy amorphous coating material containing refractory particles is 220 × 10⁻⁶. 4 mm 3 N -1 m -1 -380×10 4 mm 3 N -1 m -1 .

[0065] The third aspect of the present invention is to provide the application of the high-entropy amorphous coating material containing refractory particles prepared according to the first aspect of the present invention in offshore drilling platforms, deep-sea exploration instruments, and ships.

[0066] This invention, through precise control of the powder preparation process, enables the coating to have a uniform and defect-free internal structure, increasing both the amorphous content and the coating hardness. Unlike traditional mechanical mixing powder preparation, this invention utilizes plasma atomization technology to prepare a high-entropy amorphous alloy material mixed with refractory nanoparticles. The coating prepared using laser cladding technology exhibits advantages such as high hardness, high amorphous content, and a uniform and defect-free internal structure. Laser cladding experiments using this composite powder ensure that the high-entropy amorphous powder does not completely melt during the melting of the high-melting-point nanoparticles. The unmelted portion increases the nucleation rate of the high-entropy amorphous particles, promoting grain refinement. Furthermore, the refractory nanoparticles are dispersed throughout the coating, avoiding agglomeration problems common in traditional mixing methods, thus achieving dispersion strengthening. In addition, the melted portion of the refractory nanoparticles effectively promotes the formation of more amorphous structures in the coating (because Mo and Re can promote the formation of amorphous phases), increasing coating hardness and reducing wear rate. Attached Figure Description

[0067] Figure 1 A schematic diagram of the plasma atomization process provided for the implementation of this invention;

[0068] Figure 2 An enlarged diagram of the plasma atomization process mechanism provided for the implementation of this invention.

[0069] Explanation of reference numerals in the attached figures:

[0070] 1-High entropy amorphous alloy material feeding chamber;

[0071] 2- Heating chamber for plasma atomization;

[0072] 3-Atomization chamber;

[0073] 4-Powder collection bin;

[0074] 5-Side powder feeder;

[0075] 6-Atomizing nozzle;

[0076] 7-Refractory nanopowder;

[0077] 8-High-entropy amorphous alloy atomized droplets. Detailed Implementation

[0078] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0079] like Figure 1 As shown, this invention utilizes plasma atomization technology to manufacture high-entropy amorphous alloy materials. The specific process is as follows: the high-entropy amorphous alloy material is fed from the high-entropy amorphous alloy material feeding chamber 1 into the plasma atomization heating chamber 2, where it is melted and broken into fine high-entropy amorphous alloy atomized droplets 8 by the high-temperature plasma jet generated by the atomizing nozzle 6.

[0080] like Figure 2 As shown, during this atomization process, a side powder feeder 5, which contains a side powder feeding pipe, blows a certain amount of nanoscale refractory nanopowder (i.e., refractory nanopowder 7, such as Mo, Re, etc.) into the atomization chamber 3 through the side powder feeding pipe. These refractory nanopowders fuse together with the high-entropy amorphous metal droplets during flight and solidification. Because the melting point of powders such as Mo and Re is much higher than that of high-entropy amorphous materials, they do not melt when incorporated into the high-entropy amorphous droplets. Finally, through rapid cooling, they are made into excellent high-melting-point nanoparticle-reinforced high-entropy amorphous alloy composite powder, which is collected in the powder collection bin 4.

[0081] Example 1

[0082] Step 1: Select the CoCrFeNiBSiC composition as the initial high-entropy amorphous alloy system. This involves uniformly mixing the metal and non-metal materials, then melting and pulverizing to obtain the high-entropy amorphous alloy material. The composition of the raw material mixture of metal and non-metal powders is as follows: Co 15 wt%, Cr 15 wt%, Fe 25 wt%, Ni 15 wt%, B 10 wt%, Si 15 wt%, C 5 wt%. All metal raw materials must have a purity ≥ 99.9 wt% (to avoid impurities interfering with amorphous formation). The above raw materials are then melted using a vacuum induction melting furnace or an electric arc melting furnace (Ar atmosphere protection), with a vacuum level ≤ 10. -3 To prevent oxidation, during smelting, each smelting session lasts 30 minutes, and the smelting temperature is 1600-1700℃ (temperature fluctuates within this range); smelting is repeated 5 times to ensure uniform composition; thus, a high-entropy amorphous alloy material is obtained.

[0083] Step Two: The master alloy ingot (i.e., high-entropy amorphous alloy material) obtained in Step One is plasma atomized using plasma atomization technology. A plasma generator (power range 120 kW) is selected as the plasma gun. Inert gas (Ar) protection is used in the atomization chamber, and a cyclone separator is selected as the powder collection system. The master alloy ingot is broken into particles (particle size 1-5 mm) and continuously fed into the plasma beam through a vibrating feeder. During plasma atomization, the feeding rate of the high-entropy amorphous alloy material is 1 kg / h; the plasma temperature is set to 16000 K, and the Ar gas flow rate is set to 75 L / min. The atomization pressure is set to 8 MPa, and the high-pressure gas is used to break the molten high-entropy amorphous alloy material into tiny droplets. A side-branch powder feeding pipe is added to the atomization chamber and protected with a similar inert gas. Nanoscale Mo metal powder (particle size of 120nm) is uniformly blown into the high-entropy amorphous alloy material droplets at a feeding rate of 20g / min. The side-branch powder feeding pipe is located on the left side of the plasma atomization main equipment cavity (i.e., the equipment cavity where the plasma atomization chamber is located). The nozzle of the side-branch powder feeding pipe is located in the atomization cooling zone downstream of the axial position of the main nozzle of the plasma atomization equipment (i.e., the outlet of the high-entropy amorphous alloy material). The vertical distance between the nozzle of the side-branch powder feeding pipe and the main nozzle of the plasma atomization equipment is 120mm. The side-branch powder feeding pipe should be tilted downwards, and the angle between the axis of the side-branch powder feeding pipe and the axis of the main nozzle of the plasma atomization equipment is set to 35°. The radial distance between the side powder delivery pipe inlet and the bottom surface of the main nozzle of the plasma atomizing equipment is 10mm; the side powder delivery pipe nozzle is made of 316 stainless steel, and the high-temperature area (nozzle) uses Inconel 600 nickel-based high-temperature alloy. The inner diameter of the side powder delivery pipe nozzle is set at 2mm. A cyclone separator is used to cool and separate composite powders of different particle sizes in an inert gas environment; the cooling rate of the droplets needs to be 10... 5 -10 6 K / s (rapid cooling inhibits crystallization and forms amorphous particles), the target particle size separated by the cyclone separator is 30-60µm, which is suitable for laser cladding to prepare coatings and can uniformly feed powder.

[0084] Step 3: Use a grinding wheel to remove the oxide layer and impurities from the surface of the E690 marine steel, and then clean the ground surface with anhydrous ethanol. A 1064nm laser was used for cladding. Before cladding, the powder was dried in a drying oven at 120°C for two hours, then cooled to room temperature. The powder was then added to the powder feeder in local feeding mode. After observing powder being fed from the laser head, the feeding mode was changed to external feeding mode on the powder feeder control panel. A cladding experiment was then conducted, with the distance between the laser head nozzle and the marine steel substrate set to 15mm to ensure the laser focus and the powder at the outlet were aligned. The angle between the laser head and the horizontal plane of the substrate was 75° to prevent damage to the laser head from splashing. A robot was then used to set the starting point for laser cladding. After setting the starting point, the powder feeder flow rate and carrier gas flow rate were adjusted to preset values. In this invention, the carrier gas flow rate was 0.75MPa. After multiple tests, the powder feeding rate was set to 20g / min, and the external feeding mode was confirmed again. The scanning speed was set to 18mm / s. The laser wavelength is 1064nm, the laser power is set to 1500W, and the light output button is turned on. Then, the robot controls the laser equipment to switch the operation mode to automatic operation mode. At this time, the laser power can ensure the best cladding effect and the surface is free of obvious defects such as cracks.

[0085] The performance test results of the coatings prepared by the above method are shown in Table 1.

[0086] Example 2

[0087] It adopts the same preparation method as Example 1, the only difference being that the refractory nanopowder used is selected from Re powder (particle size of 120nm).

[0088] Example 3

[0089] It adopts the same preparation method as Example 1, the only difference being that the refractory nanopowder used is selected from Y2O3 powder (particle size of 120nm).

[0090] Example 4

[0091] Step 1: Select the AlCoCrFeNiBSi composition as the initial high-entropy amorphous alloy system. This involves uniformly mixing the metallic and non-metallic materials, melting, and pulverizing to obtain the high-entropy amorphous alloy material. The composition of the raw material mixture of metallic and non-metallic powders is as follows: Al 15wt%, Co 10wt%, Cr 15wt%, Fe 25wt%, Ni 15wt%, B 10wt%, Si 10wt%. All metallic raw materials must have a purity ≥ 99.9wt% (to avoid impurities interfering with amorphous formation). The above raw materials are then melted using a vacuum induction melting furnace with a vacuum level ≤ 10.-3 To prevent oxidation, during smelting, each smelting session lasts 30 minutes, and the smelting temperature is 1600-1700℃ (temperature fluctuates within this range); smelting is repeated 5 times to ensure uniform composition; thus, a high-entropy amorphous alloy material is obtained.

[0092] Step Two: The master alloy ingot obtained in Step One is plasma atomized using plasma atomization technology. A plasma generator (power range 150kW) is selected as the plasma gun. Inert gas (He) is used for protection in the atomization chamber, and a cyclone separator is selected as the powder collection system. The master alloy ingot is broken into particles (particle size 1-5 mm), which are continuously fed into the plasma beam through a vibrating feeder. During plasma atomization, the feeding rate of the high-entropy amorphous alloy material is 1.2 kg / h; the plasma temperature is set to 16000 K, and the He gas flow rate is set to 60 L / min. The atomization pressure is set to 10 MPa, and the high-pressure gas is used to break the molten high-entropy amorphous alloy material into tiny droplets. A side-branch powder delivery pipe is added to the atomization chamber, protected by a similar inert gas. Nanoscale La2O3 powder (100nm particle size) is uniformly blown into the molten metal droplets at a delivery rate of 20g / min. The side-branch powder delivery pipe is located on the left side of the main plasma atomization equipment chamber. The nozzle of the side-branch powder delivery pipe is located downstream of the main nozzle (i.e., the outlet of the high-entropy amorphous alloy material) in the atomization cooling zone, with a vertical distance of 120mm between the nozzle and the main nozzle. The side-branch powder delivery pipe should be tilted downwards, with the angle between its axis and the main nozzle axis set at 35°. The radial distance between the nozzle of the side-branch powder delivery pipe and the bottom surface of the main nozzle is 10mm. The side-branch powder delivery pipe is made of 316 stainless steel, while the high-temperature area (nozzle) uses Inconel 600 nickel-based high-temperature alloy. The inner diameter of the nozzle is set to 2mm. A cyclone separator is used to cool and separate composite powders of different particle sizes in an inert gas environment; the cooling rate of the droplets needs to be at least 10. 5 -10 6 K / s (rapid cooling inhibits crystallization and forms amorphous particles), the target particle size separated by the cyclone separator is 30-60µm, which is suitable for laser cladding to prepare coatings and can uniformly feed powder.

[0093] Step 3: Use a grinding wheel to remove the oxide layer and impurities from the surface of the E690 marine steel, and then clean the ground surface with anhydrous ethanol. A 1064nm laser was used for cladding. Before cladding, the powder was dried in a drying oven at 120°C for two hours, then cooled to room temperature. The powder was then added to the powder feeder in local feeding mode. After observing powder being fed from the laser head, the feeding mode was changed to external feeding mode on the powder feeder control panel. A cladding experiment was then conducted, with the distance between the laser head nozzle and the marine steel substrate set to 15mm to ensure the laser focus and the powder at the outlet were aligned. The angle between the laser head and the horizontal plane of the substrate was 75° to prevent damage to the laser head from splashing. A robot was then used to set the starting point for laser cladding. After setting the starting point, the powder feeder flow rate and carrier gas flow rate were adjusted to preset values. In this invention, the carrier gas flow rate was 0.65MPa. After multiple tests, the powder feeding rate was set to 25g / min, and the external feeding mode was confirmed again. The scanning speed was set to 20mm / s. The laser power is set to 1500W and the light output button is turned on. Then, the robot controls the laser equipment to switch the operating mode to automatic mode. At this time, the laser power can ensure the best cladding effect and there are no obvious defects such as cracks or fissures on the surface.

[0094] The performance test results of the coatings prepared by the above method are shown in Table 1.

[0095] Comparative Example 1

[0096] It adopts the same preparation method as Example 1, the only difference being that the refractory nano powder Mo powder is not added to the laser cladding powder, and only high-entropy amorphous alloy material is used.

[0097] Comparative Example 2

[0098] It adopts the same preparation method as Example 1, except that the high-entropy amorphous alloy material and Mo powder are directly mixed evenly in the powder used for laser cladding.

[0099] Comparative Example 3

[0100] It adopts the same preparation method as Example 1, except that the CoCrFeNiBSiC raw material is replaced with FeSiB (Fe 75 wt%, B 10 wt%, Si 15 wt%) to prepare amorphous alloy powder.

[0101] Table 1

[0102]

[0103] The results of the embodiments show that the preparation method proposed in this invention, which involves embedding refractory nanoparticles into high-entropy amorphous alloy droplets during plasma atomization, has successfully prepared a composite coating with high amorphous content, high hardness, and excellent wear resistance.

[0104] By comparing the examples with Comparative Example 1, it is shown that the composite powder prepared by introducing refractory nanoparticles into high-entropy amorphous alloy droplets can significantly increase the amorphous content of the coating, reduce hardness, and decrease wear rate.

[0105] By comparing the examples with Comparative Example 2, it is shown that the composite powder prepared by introducing refractory nanoparticles into high-entropy amorphous alloy droplets can significantly increase the amorphous content and hardness of the coating and reduce the wear rate compared with physically mixed refractory nanoparticles.

[0106] By comparing the examples with Comparative Example 3, it is shown that only composite powder prepared by introducing refractory nanoparticles into the specific high-entropy amorphous alloy system of the present invention can significantly increase the amorphous content of the coating, reduce hardness, and decrease wear rate.

[0107] The above embodiments are merely illustrative examples and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for preparing a high-entropy amorphous coating material containing refractory particles, characterized in that, Includes the following steps: (1) After mixing the metal and non-metal materials evenly, melt and crush them to obtain a high-entropy amorphous alloy material; (2) The high-entropy amorphous alloy material is plasma-atomized, and refractory nanoparticles are blown into the high-entropy amorphous alloy droplets formed after atomization. The mixture is then cooled and sieved to obtain composite powder suitable for laser cladding. The melting point of the refractory nanoparticles is greater than that of the high-entropy amorphous alloy material. (3) The composite powder is loaded onto the substrate by laser cladding to form a high-entropy amorphous coating material containing refractory particles.

2. The method for preparing a high-entropy amorphous coating material containing refractory particles according to claim 1, characterized in that: Step (1), The metal is selected from at least one of Fe, Co, Ni, Cr, Mn, Al, Ti, or Cu; and / or, The non-metallic material is selected from at least one of B, Si, P, or C; and / or, The melting is carried out using a vacuum induction melting furnace or an electric arc melting furnace under a protective atmosphere.

3. The method for preparing a high-entropy amorphous coating material containing refractory particles according to claim 2, characterized in that: Step (1), in the high-entropy amorphous alloy material, based on the total mass of the metal and non-metal materials as 100%, the following amounts are added: Co 10wt%-20wt%, Cr 10wt%-20wt%, Fe 20wt%-30wt%; Ni 10wt%-20wt%, B 5wt%-10wt%, Si 10wt%-15wt%, and C 5wt%-10wt%; or, In high-entropy amorphous alloy materials, based on the total mass of metallic and non-metallic raw materials as 100%, the following amounts are added: Al 10-20 wt%, Co 5-15 wt%, Cr 10-20 wt%, Fe 20-30 wt%, Ni 10-20 wt%, B 5-15 wt%, and Si 5-15 wt%. The melting temperature is 1500-1700℃; and / or, The melting is carried out in a vacuum induction melting furnace with a vacuum degree ≤10. -3 Pa; and / or, During the aforementioned smelting process, each smelting session lasts 15-45 minutes; and / or, The melting process is repeated 3-5 times; and / or, After being pulverized, the particle size of the high-entropy amorphous alloy material is 1-5 mm.

4. The method for preparing a high-entropy amorphous coating material containing refractory particles according to claim 1, characterized in that: Step (2), During plasma atomization, the plasma atomization temperature is 10000-20000 K; and / or, During plasma atomization, the feed rate of the high-entropy amorphous alloy material is 0.5-2 kg / h; and / or, The gas used during plasma atomization is a protective gas, and the flow rate of the protective gas is 50-100 L / min; and / or, The atomization pressure during plasma atomization is 2-10 MPa.

5. The method for preparing a high-entropy amorphous coating material containing refractory particles according to claim 1, characterized in that: Step (2), The refractory nanopowder is selected from at least one of Mo, Re, Y₂O₃, and La₂O₃; and / or, The refractory nanoparticles have a particle size of 100-200 nm; and / or, A side-branch powder feeding pipe is added to the plasma atomization chamber, and a protective gas of the same type as that used in plasma atomization is used for protection. Refractory nanoparticles are blown into high-entropy amorphous alloy droplets through the side-branch powder feeding pipe, wherein the powder feeding rate of the refractory nanoparticles is 15-25 g / min; and / or, Composite powders of different particle sizes are cooled and separated in an inert gas environment using a cyclone separator; and composite powders suitable for laser cladding are screened out, wherein the particle size of the composite powder is 30-60µm.

6. The method for preparing a high-entropy amorphous coating material containing refractory particles according to claim 1, characterized in that: Step (3), The substrate is a marine steel substrate; and / or The distance between the laser head nozzle and the substrate in the laser cladding process is set to 14-25 mm; and / or, The angle between the laser head of the laser cladding and the horizontal plane of the substrate is 75°-85°.

7. The method for preparing a high-entropy amorphous coating material containing refractory particles according to claim 1, characterized in that: Step (3), The powder feeding rate for laser cladding is set to 15-25 g / min; and / or, During the laser cladding process, the scanning speed of the laser head is 15mm / s-20mm / s; and / or, The laser used for laser cladding is a laser with a wavelength of 1000-1100 nm; and / or, During laser cladding, the laser power is 1400-1900W.

8. A high-entropy amorphous coating material containing refractory particles prepared by the method according to any one of claims 1-7.

9. The high-entropy amorphous coating material containing refractory particles according to claim 8, characterized in that, The amorphous content of the high-entropy amorphous coating material containing refractory particles is 40-60 wt%; The hardness of the high-entropy amorphous coating material containing refractory particles is 1000-1300 HV. 0.5 ; The wear rate of the high-entropy amorphous coating material containing refractory particles is 220 × 10⁻⁶. 4 mm 3 N -1 m -1 -380×10 4 mm 3 N - 1 m -1 .

10. The application of the high-entropy amorphous coating material containing refractory particles prepared by the method according to any one of claims 1-7 in offshore drilling platforms, deep-sea exploration instruments, and ships.

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