High-entropy alloy coating and preparation method and application thereof

Abstract

The invention discloses a high-entropy alloy coating, which relates to the technical field of alloy coatings and adopts the following metal powder in percentage by weight: 10-12% of Co, 18-20% of Cr, 20-22% of Fe, 5-7% of Mo, 10-15% of TiB2 and the balance of Ni. The high-entropy alloy formula is excellent in comprehensive performance and suitable for high-temperature, high-corrosion and high-abrasion extreme working condition environments; according to the high-entropy alloy coating prepared through the method, the hardness is larger than or equal to 65 HRC, the thickness of the coating is larger than or equal to 1.2 mm, and the coating is compact, few in micropores and free of cracks; and meanwhile, the 700 DEG C high-temperature oxidation resistance and the conventional corrosion resistance of the base material are effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of alloy coatings, and particularly relates to a high-entropy alloy coating, a preparation method thereof, and an application thereof. Background Art

[0002] Coal mine scraper conveyors are widely used in coal mining faces underground. During coal mining operations, it closely adheres to the coal shearer and timely pushes and conveys the mined coal from the coal mining site along the chute of the scraper conveyor to the rear. Whether it is a horizontally mined coal seam or a working face with a certain inclination angle, the scraper conveyor can work stably and continuously transport the coal to subsequent transportation links, such as mine cars or belt conveyors, to achieve efficient coal transportation.

[0003] In actual operation, the metal coating on the scraper surface faces severe wear tests. Due to hard impurities such as gangue mixed in the coal, during the process of the scraper scraping and pushing the material, it will cause strong friction and scratching on the metal coating, resulting in the gradual wear and thinning of the coating. Especially at the edges and bottoms where the scraper is in frequent contact with the material, the wear is more obvious. At the same time, there is also a certain amount of friction between the scraper and the chute during operation, further exacerbating the wear of the metal coating. Under such harsh working conditions for a long time, problems such as local peeling and uneven wear of the metal coating may occur, affecting the service life and transportation efficiency of the scraper. Therefore, the metal coating must have high wear resistance to resist the double friction and wear of the material and the chute, ensure that the coating is not quickly worn through during long-term use of the scraper, and maintain a good working state.

[0004] Moreover, the metal coating should have excellent corrosion resistance because the underground environment of coal mines is humid and there may also be corrosive gases. The coating needs to protect the scraper substrate from corrosion and extend the overall life of the scraper. In addition, the metal coating should have good adhesion to the scraper substrate to ensure that the coating does not easily fall off when subjected to impact and vibration. At the same time, the coating should also have a certain hardness and toughness, which can withstand the impact of the material while resisting wear and prevent cracks or breakage due to excessive brittleness.

[0005] Therefore, providing a coating with high wear resistance, high corrosion resistance, and a certain hardness and toughness is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0006] In order to solve the above problems, the purpose of the present invention is to provide a high-entropy alloy coating, a preparation method thereof, and an application thereof.

[0007] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0008] A high-entropy alloy coating, using metal powders in the following weight percentages:

[0009] 10 - 12% Co, 18 - 20% Cr, 20 - 22% Fe, 5 - 7% Mo, 10 - 15% TiB2, the balance being Ni.

[0010] In the metal powder of the present invention, the Co element can maintain high strength and hardness in a high - temperature environment, and at the same time has good corrosion resistance, and is an important component element in superalloys; the Cr element forms a dense Cr2O3 passivation film on the surface of the alloy, significantly improving the corrosion resistance and high - temperature oxidation resistance of the alloy; the Fe element, as a matrix element, can stabilize the phase structure of the alloy, providing good mechanical properties and processing properties; the Ni element helps to stabilize the FCC structure, improve the toughness and ductility of the alloy, and at the same time enhance the high - temperature performance of the alloy; the addition of the Mo element further improves the high - temperature strength and corrosion resistance of the alloy, especially its performance in an acidic environment is particularly prominent; the addition of TiB2 can significantly refine the grains, improve the hardness and wear resistance of the alloy, and at the same time, by forming a boride strengthening phase, further enhance the mechanical properties and high - temperature stability of the alloy; in summary, the high - entropy alloy formula has excellent comprehensive performance and is suitable for extreme working conditions of high temperature, high corrosion and high wear.

[0011] Preferably, the particle size of the metal powder is 15 - 53 μm.

[0012] Preferably, the coating is combined with the substrate through a slurry and then surfacing - welded. The thickness of the slurry is 1 - 1.5 mm, and the thickness of the coating after surfacing - welding is 1 - 1.5 mm.

[0013] Preferably, the slurry comprises a binder and the metal powder in a mass ratio of 35 - 50:65 - 50.

[0014] Preferably, the binder comprises the following raw materials in weight percentages: 1 - 5% carboxymethyl cellulose, 1 - 3% polyvinyl alcohol, 5 - 10% silica sol, 1 - 3% aluminum dihydrogen phosphate, and the balance being absolute ethanol.

[0015] In the binder of the present invention, carboxymethyl cellulose is the main component of the binder, providing excellent binding properties and film-forming ability, enabling the coating to adhere uniformly and firmly to the substrate surface, while endowing the binder with good flexibility and water solubility, facilitating processing and adjustment; polyvinyl alcohol further enhances the mechanical strength and water resistance of the binder, improving the durability and anti-peeling performance of the coating; silica sol has excellent thermal stability and chemical stability, capable of maintaining the structural integrity of the coating in high-temperature environments, while enhancing the hardness and wear resistance of the coating; the addition of aluminum dihydrogen phosphate significantly improves the heat resistance of the coating, enabling it to maintain high bonding strength and hardness in high-temperature environments, and its rapid curing characteristic helps to improve production efficiency; absolute ethanol as a diluent effectively adjusts the viscosity of the slurry, improves the fluidity and coating performance of the slurry, ensuring uniform distribution of the coating and easy construction; in summary, this formulation has a low overall cost and excellent process performance, and is suitable for a variety of industrial application scenarios.

[0016] According to the above-mentioned preparation method of a high-entropy alloy coating, it includes the following steps:

[0017] (1) Prepare high-entropy alloy powder: Weigh the metal powders according to the described mass percentages, mix them evenly, and set aside.

[0018] (2) Prepare the slurry: Weigh the raw materials of the slurry according to the described weight ratio, mix them evenly, and set aside.

[0019] (3) Immerse the substrate in the slurry for slurry coating, and then carry out curing and drying in sequence.

[0020] (4) Clad the high-entropy alloy powder on the surface of the substrate obtained in step (3).

[0021] The surfacing process adopted in the present invention can achieve uniform heat distribution, ensure the formation of a firm metallurgical bond between the coating and the substrate, and significantly improve the bonding strength and wear resistance of the coating; this method has a mature process, can flexibly adjust the thickness and composition of the coating to meet different working conditions requirements, and the high stability of the surfacing process effectively guarantees the production efficiency; in addition, the heat input during the surfacing process is relatively uniform, which can effectively reduce the thermal deformation and thermal stress of the substrate material, ensuring the overall performance and service life of the scraper.

[0022] Preferably, the method for mixing evenly in step (1) is: Place it in a ball mill at a ball-to-material ratio of 3:1 and grind for 3 - 6 h, and the rotational speed of the ball mill is 300 - 400 r / min.

[0023] The method for mixing evenly in step (2) is: Place the raw materials in a ball mill and grind for 2 - 3 h, and the rotational speed of the ball mill is 300 - 400 r / min.

[0024] Preferably, the substrate is pretreated before being immersed in step (3). The steps are as follows: sandblast the substrate, then ultrasonically clean the surface of the substrate, and subsequently dry it at 80 - 100 °C for 30 - 60 min;

[0025] The curing is as follows: leave it standing in air at room temperature for 12 - 24 h;

[0026] The drying is as follows: keep it warm at 80 - 100 °C for 180 - 240 min

[0027] Preferably, the parameters of the cladding in step (4) are as follows: the distance between the surfacing equipment and the substrate is 10 - 20 mm, the current of the surfacing equipment is 150 - 200 A, the voltage is 25 - 30 V, the powder feeding speed is 8 - 15 g / min, and the scanning speed is 8 - 15 mm / s.

[0028] Application of the high - entropy alloy coating as described above or the high - entropy alloy coating obtained by the above - described preparation method in a coal mine scraper conveyor.

[0029] High - entropy alloy is a new type of alloy composed of five or more main elements. It has unique properties. Firstly, it has high hardness, which stems from its complex atomic structure, enabling it to effectively resist external force deformation. When applied to easily worn parts such as scrapers, it can significantly improve the wear - resistance ability. Secondly, high - entropy alloy has good corrosion resistance and can stably exist in complex chemical environments, making it suitable for the humid and possibly corrosive gas - containing scenarios in coal mine shafts. Moreover, it has good high - temperature stability and can still maintain its mechanical properties at high temperatures, ensuring that the scraper can operate normally under special working conditions, providing a new material selection direction for the metal coating of the scraper of the coal mine scraper conveyor. The method of preparing a coating on the surface of the scraper of the coal mine scraper conveyor by using high - entropy alloy slurry through the surfacing process of the present invention has significant advantages in terms of equipment cost, process stability, and coating performance.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] The high - entropy alloy formula of the present invention has excellent comprehensive performance and is applicable to extreme working conditions of high temperature, high corrosion, and high wear. The high - entropy alloy coating prepared by using the present invention has a hardness ≥ 65 HRC, a coating thickness ≥ 1.2 mm, the coating is dense, has few micropores, and no cracks; the wear - resistance performance is improved by ≥ 28 times, and at the same time, it effectively improves the high - temperature oxidation resistance of the substrate at 700 °C and the resistance to conventional corrosion. Description of the Drawings

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the provided drawings.

[0033] Figure 1 It is the surface morphology diagram after slurry hanging and drying in Embodiment 1 of the present invention;

[0034] Figure 2 It is the surface morphology diagram after surfacing in Embodiment 1 of the present invention;

[0035] Figure 3 It is the surface morphology diagram after slurry hanging and drying in Embodiment 2 of the present invention;

[0036] Figure 4 It is the surface morphology diagram after surfacing in Embodiment 2 of the present invention;

[0037] Figure 5 It is the surface morphology diagram after slurry hanging and drying in Embodiment 3 of the present invention;

[0038] Figure 6 It is the surface morphology diagram after surfacing in Embodiment 3 of the present invention;

[0039] Figure 7 It is the surface morphology diagram after slurry hanging and drying in Embodiment 4 of the present invention;

[0040] Figure 8 It is the surface morphology diagram after surfacing in Embodiment 4 of the present invention. Detailed implementation manners

[0041] The following describes the embodiments of the present invention. The described embodiments are exemplary and are intended to explain the present invention, rather than being construed as a limitation to the present invention.

[0042] Embodiment 1

[0043] The present invention provides a method for preparing a high-entropy alloy coating, and the specific steps are as follows:

[0044] (1) Prepare the substrate: Sandblast the scraper, clean the surface of the scraper using an ultrasonic cleaning device, and then place it in a drying oven and dry it at 80 °C for 60 min to ensure that the surface is completely dry;

[0045] (2) Prepare the high-entropy alloy powder and the binder: Prepare the high-entropy alloy powder according to 10% Co, 20% Cr, 22% Fe, 5% Mo by weight percentage, and the balance is Ni. Place it in a ball mill at a ball-to-material ratio of 3:1 and grind for 6 h. The rotation speed of the ball mill is 300 r / min. After taking it out, seal it for storage to prevent moisture absorption or contamination;

[0046] Binder: According to the mass percentage, configure the binder with 4% carboxymethyl cellulose, 1% polyvinyl alcohol, 8% silica sol, 1% aluminum dihydrogen phosphate, and the rest being absolute ethanol;

[0047] (3) Prepare the slurry: Place the slurry in a ball mill according to the ratio of 50wt% high-entropy alloy powder and the rest being the binder, grind for 2h, the rotational speed of the ball mill is 300r / min, take it out and store it sealed to prevent drying or delamination;

[0048] (4) Apply the slurry: Immerse the dried scraper into the slurry, and gently stir if necessary. After ensuring that the entire surface is coated with the slurry, take it out. If the thickness on the surface of the scraper fails to reach the expected standard (1 - 1.5mm), immerse it in the slurry again to increase the thickness. Take out the scraper after applying the slurry and let it stand for a while to allow the excess slurry to drip naturally; Place the scraper after applying the slurry in a dry place and let it stand for 12h to allow the slurry to initially cure, then place it in a drying oven and keep it warm at 100°C for 180min to fully dry the slurry and prevent defects such as cracks during the surfacing process;

[0049] (5) Surfacing: Fix the dried scraper through a chuck, place it flat on the carrier, adjust the distance between the surfacing equipment and the specimen to 17mm, set the running track of the surfacing equipment. According to the characteristics of the high-entropy alloy powder, set the current of the surfacing equipment to 180A, the voltage to 25V, the powder feeding speed to 10g / min, and the scanning speed to 12mm / s. Start the surfacing equipment and perform surfacing according to the set parameters to ensure that the surfacing layer is uniform and defect-free; Take down the scraper after surfacing and perform subsequent processing. Wash the residue on the surface of the specimen with running water, then clean it again with alcohol to ensure the surface is clean. Finally, perform a drying treatment to form a high-entropy alloy coating with high stability, wear resistance, and corrosion resistance. The thickness of the coating is 1.2mm, measure its Vickers hardness to be 458.7HV, use a friction and wear testing machine to conduct a wear test, adopt a reciprocating wear method, the wear time is 30 minutes, the stroke is 5mm, the load is 15N, the wear pair is Si3N4, and after wear, use a white light interferometer to measure the wear volume, and calculate the wear rate through where W is the wear rate, V is the wear volume, F is the load, L is the wear stroke, and the wear rate of the coating is measured to be 1.28×10 -4 .

[0050] Example 2

[0051] The present invention provides a method for preparing a high-entropy alloy coating, and the specific steps are as follows:

[0052] (1) Prepare the substrate: Sandblast the scraper, clean the surface of the scraper using an ultrasonic cleaning device, and then place it in a drying oven and dry it at 80°C for 60min to ensure the surface is completely dry;

[0053] (2) Prepare the high-entropy alloy powder and binder: According to the weight percentages of 10% Co, 20% Cr, 22% Fe, 5% Mo, 10% TiB2, and the balance being Ni, prepare the high-entropy alloy powder. Place it in a ball mill at a ball-to-material ratio of 3:1 and grind for 6 h. The rotational speed of the ball mill is 300 r / min. After taking it out, store it sealed to prevent moisture absorption or contamination;

[0054] Binder: Prepare the binder according to the composition of 4% carboxymethyl cellulose, 1% polyvinyl alcohol, 8% silica sol, 1% aluminum dihydrogen phosphate, and the rest being absolute ethanol by mass percentage;

[0055] (3) Prepare the slurry: Place the slurry in a ball mill according to the ratio of 50 wt% high-entropy alloy powder and the rest being the binder and grind for 2 h. The rotational speed of the ball mill is 300 r / min. After taking it out, store it sealed to prevent drying or delamination;

[0056] (4) Coating: Immerse the dried scraper into the slurry, and gently stir if necessary. After ensuring that the entire surface is coated with the slurry, take it out. If the thickness on the surface of the scraper fails to reach the expected standard (1 - 1.5 mm), immerse it in the slurry again to increase the thickness. Take out the coated scraper and let it stand for a while to allow the excess slurry to drip naturally; Place the coated scraper in a dry place in the air and let it stand for 12 h to preliminarily cure the slurry, and then place it in a drying oven and keep it at 100 °C for 180 min to fully dry the slurry (see Figure 1 ), to prevent defects such as cracks from occurring during the surfacing process;

[0057] (5) Surfacing: Fix the dried scraper through a chuck, place it flat on the carrier, adjust the distance between the surfacing equipment and the specimen to 17 mm, set the running track of the surfacing equipment. According to the characteristics of the high-entropy alloy powder, set the current of the surfacing equipment to 180 A, the voltage to 25 V, the powder feeding speed to 10 g / min, and the scanning speed to 12 mm / s. Start the surfacing equipment and perform surfacing according to the set parameters to ensure that the surfacing layer is uniform and defect-free; Take down the scraper after surfacing and perform subsequent treatment. Wash the residue on the surface of the specimen with running water, and then clean it again with alcohol to ensure the surface is clean. Finally, perform a drying treatment (see Figure 2 ), to form a high-entropy alloy coating with high stability, wear resistance, and corrosion resistance. The thickness of the coating is 1.24 mm. Measure its Vickers hardness to be 928.6 HV. Use a friction and wear testing machine to conduct a wear test. Adopt the reciprocating wear method, with a wear time of 30 minutes, a stroke of 5 mm, a load of 15 N, and the wear pair being Si3N4. After wear, use a white light interferometer to measure the wear volume, and calculate the wear rate through where W is the wear rate, V is the wear volume, F is the load, and L is the wear stroke. The measured wear rate of the coating is 1.03×10 -4 .

[0058] Example 3

[0059] The present invention provides a method for preparing a high-entropy alloy coating, and the specific steps are as follows:

[0060] (1) Prepare the substrate: Sandblast the scraper, clean the surface of the scraper using an ultrasonic cleaning device, and then place it in a drying oven and dry it at 90 °C for 45 min to ensure that the surface is completely dry;

[0061] (2) Prepare the high-entropy alloy powder and the binder: Prepare the high-entropy alloy powder according to the weight percentages of 11% Co, 19% Cr, 21% Fe, 6% Mo, 12% TiB2, and the balance being Ni. Place it in a ball mill at a ball-to-material ratio of 3:1 and grind for 6 h. The rotation speed of the ball mill is 350 r / min. After taking it out, seal it for storage to prevent moisture absorption or contamination;

[0062] Binder: Prepare the binder according to the composition of 3% carboxymethyl cellulose, 2% polyvinyl alcohol, 7% silica sol, 2% aluminum dihydrogen phosphate, and the balance being absolute ethanol by mass percentage;

[0063] (3) Prepare the slurry: Place the slurry with a ratio of 55% high-entropy alloy powder and the balance being the binder in a ball mill and grind for 2 h. The rotation speed of the ball mill is 350 r / min. After taking it out, seal it for storage to prevent drying or delamination;

[0064] (4) Coating: Immerse the dried scraper in the slurry, and gently stir if necessary. After ensuring that the entire surface is coated with the slurry, take it out. If the thickness of the surface of the scraper fails to reach the expected standard (1 - 1.5 mm), it can be immersed in the slurry again to increase the thickness. Take out the coated scraper and let it stand for a while to allow the excess slurry to drip naturally; Place the coated scraper in a place with air drying and let it stand for 12 h to allow the slurry to initially solidify, and then place it in a drying oven and keep it at 100 °C for 200 min to fully dry the slurry (see Figure 3 ), to prevent defects such as cracks from occurring during the surfacing process;

[0065] (5) Surfacing: Fix the dried scraper through a chuck, place it flat on the carrier, adjust the distance between the surfacing equipment and the specimen to 17 mm, set the running track of the surfacing equipment, and according to the characteristics of the high-entropy alloy powder, set the current of the surfacing equipment to 180 A, the voltage to 25 V, the powder feeding speed to 10 g / min, and the scanning speed to 12 mm / s. Start the surfacing equipment and perform surfacing according to the set parameters to ensure that the surfacing layer is uniform and defect-free; Take down the scraper after surfacing and perform subsequent treatment. Wash the residue on the surface of the specimen with running water, and then clean it with alcohol again to ensure that the surface is clean. Finally, perform a drying treatment (see Figure 4), a high-entropy alloy coating with high stability, wear resistance, and corrosion resistance is formed. The thickness of the coating is 1.21 mm, and its Vickers hardness is measured to be 945.3 HV. A wear test is carried out using a friction and wear testing machine in a reciprocating wear mode for 30 minutes with a stroke of 5 mm and a load of 15 N. The wear pair is Si3N4. After wear, a white light interferometer is used to measure the wear volume, and the wear rate is calculated through where W is the wear rate, V is the wear volume, F is the load, and L is the wear stroke. The wear rate of the coating is measured to be 1.52×10 -5 .

[0066] Example 4

[0067] The present invention provides a method for preparing a high-entropy alloy coating, and the specific steps are as follows:

[0068] (1) Prepare the substrate: Sandblast the scraper, clean the surface of the scraper using an ultrasonic cleaning device, and then place it in a drying oven and dry it at 100 °C for 30 min to ensure that the surface is completely dry;

[0069] (2) Prepare the high-entropy alloy powder and the binder: Prepare the high-entropy alloy powder according to the weight percentages of 12% Co, 18% Cr, 20% Fe, 7% Mo, 15% TiB2, and the balance Ni. Place it in a ball mill at a ball-to-material ratio of 3:1 and grind for 6 h at a ball mill speed of 400 r / min. After taking it out, store it sealed to prevent moisture absorption or contamination;

[0070] Binder: Prepare the binder according to the composition of 2% carboxymethyl cellulose, 3% polyvinyl alcohol, 6% silica sol, 3% aluminum dihydrogen phosphate, and the rest being absolute ethanol by mass percentage;

[0071] (3) Prepare the slurry: Place the slurry with a ratio of 50% high-entropy alloy powder and the rest being the binder in a ball mill and grind for 2 h at a ball mill speed of 400 r / min. After taking it out, store it sealed to prevent drying or delamination;

[0072] (4) Apply the slurry: Immerse the dried scraper in the slurry and stir slightly to ensure that the entire surface is coated with the slurry and then take it out. If the thickness on the surface of the scraper fails to reach the expected standard (1 - 1.5 mm), it can be immersed in the slurry again to increase the thickness. Take out the scraper after applying the slurry and let it stand for a while to allow the excess slurry to drip naturally; Place the scraper after applying the slurry in a dry place and let it stand for 12 h to allow the slurry to preliminarily solidify, and then place it in a drying oven and keep it at 100 °C for 220 min to allow the slurry to dry thoroughly (see Figure 5 ), to prevent defects such as cracks from occurring during the surfacing process;

[0073] (5) Surfacing: Fix the dried scraper through the chuck, place it flat on the carrier, adjust the distance between the surfacing equipment and the specimen to 17 mm, set the running track of the surfacing equipment. According to the characteristics of the high-entropy alloy powder, set the current of the surfacing equipment to 180 A, the voltage to 25 V, the powder feeding speed to 10 g / min, and the scanning speed to 12 mm / s. Start the surfacing equipment and perform surfacing according to the set parameters to ensure that the surfacing layer is uniform and defect-free; Remove the scraper after surfacing and perform subsequent processing. Wash the residue on the surface of the specimen with running water, and then wash it again with alcohol to ensure the surface is clean. Finally, perform drying treatment (see Figure 6 ), to form a high-entropy alloy coating with high stability, wear resistance and corrosion resistance. The thickness of the coating is 1.23 mm, and its Vickers hardness is measured to be 981.7 HV. Use a friction and wear testing machine to conduct wear tests. Adopt the reciprocating wear method, with a wear time of 30 minutes, a stroke of 5 mm, a load of 15 N, and a wear pair of Si3N4. After wear, use a white light interferometer to measure the wear volume, and calculate the wear rate through , where W is the wear rate, V is the wear volume, F is the load, and L is the wear stroke. The wear rate of the coating is measured to be 3.57×10 -6 .

[0074] From the Vickers hardness data obtained in Examples 1-4, it can be seen that the addition amount of TiB2 plays a crucial role in improving the hardness of the high-entropy alloy coating. As the content of TiB2 gradually increases, the hardness of the high-entropy alloy coating shows a significant step-by-step increase; This is because TiB2 has extremely high hardness and good chemical stability, and is evenly dispersed in the coating. It hinders the movement of dislocations through the dispersion strengthening mechanism, thereby effectively improving the overall hardness of the coating; At the same time, the interfacial structure formed between TiB2 and the high-entropy alloy matrix further enhances the internal bonding force of the coating, making the hardness improvement effect more obvious. Although the addition of TiB2 can significantly improve the performance of the high-entropy alloy, too high a content may also lead to uneven stress distribution inside the coating, thus forming cracks in the bonding area and affecting the overall performance and service life of the coating.

[0075] According to Figures 1-8 it can be seen that the high-entropy alloy coating prepared by this process exhibits excellent integrity. The surface of the coating is flat and uniform, without defects such as cracks, shrinkage cavities, and bubbles visible to the naked eye; This is due to the precise control of the material composition ratio, surfacing cooling rate, and surfacing deposition rate in the process of the present invention, which enables the alloying elements to achieve uniform diffusion during solidification, avoiding the formation of defects caused by stress concentration or gas residue.

[0076] The high-entropy alloy coating prepared by using the present invention has a hardness ≥ 65 HRC, a coating thickness ≥ 1.2 mm, and the coating is dense, has few micropores and no cracks; the wear resistance is improved by ≥ 28 times, and at the same time, the high-temperature oxidation resistance and conventional corrosion resistance of the substrate are effectively improved.

[0077] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A high-entropy alloy coating, characterized in that, The metal powder used has the following weight percentages: 10 - 12% Co, 18 - 20% Cr, 20 - 22% Fe, 5 - 7% Mo, 10 - 15% TiB2, and the balance is Ni.

2. The high-entropy alloy coating according to claim 1, wherein The particle size of the metal powder is 15 - 53 μm.

3. The high-entropy alloy coating according to claim 1, wherein The coating is combined with the substrate through the slurry and then surfacing is carried out. The thickness of the slurry is 1 - 1.5 mm, and the thickness of the coating after surfacing is 1 - 1.5 mm.

4. The high-entropy alloy coating according to claim 3, wherein The slurry includes a binder and the metal powder with a mass ratio of 35 - 50:65 - 50.

5. The high-entropy alloy coating according to claim 4, wherein, The binder includes the following raw materials by weight percentage: 1 - 5% carboxymethyl cellulose, 1 - 3% polyvinyl alcohol, 5 - 10% silica sol, 1 - 3% aluminum dihydrogen phosphate, and the rest is absolute ethanol.

6. The preparation method of a high-entropy alloy coating according to any one of claims 1-5, characterized in that, It includes the following steps: (1) Prepare the high-entropy alloy powder: Weigh the metal powder according to the said mass percentage, mix evenly, and set aside; (2) Prepare the slurry: Weigh the raw materials of the slurry according to the said weight ratio, mix evenly, and set aside; (3) Immerse the substrate in the slurry for slurry coating, and then carry out curing and drying in sequence; (4) Clad the high-entropy alloy powder on the surface of the substrate obtained in step (3).

7. The preparation method of a high-entropy alloy coating according to claim 6, characterized in that, The method of mixing evenly in step (1) is: Place it in a ball mill according to a ball-to-material ratio of 3:1 and grind for 3 - 6 h, and the rotational speed of the ball mill is 300 - 400 r / min; The method of mixing evenly in step (2) is: Place the raw materials in a ball mill and grind for 2 - 3 h, and the rotational speed of the ball mill is 300 - 400 r / min.

8. The preparation method of a high-entropy alloy coating according to claim 6, characterized in that, Before immersing in step (3), the substrate is pretreated. The steps are: Carry out sandblasting treatment on the substrate, then ultrasonically clean the surface of the substrate, and then dry it at 80 - 100 °C for 30 - 60 min; The curing is: Let it stand in the air at room temperature for 12 - 24 h; The drying is: Keep it warm at 80 - 100 °C for 180 - 240 min.

9. The preparation method of a high-entropy alloy coating according to claim 6, characterized in that The parameters of the cladding in step (4) are: The distance between the surfacing equipment and the substrate is 10 - 20 mm, the current of the surfacing equipment is 150 - 200 A, the voltage is 25 - 30 V, the powder feeding speed is 8 - 15 g / min, and the scanning speed is 8 - 15 mm / s.

10. The application of the high-entropy alloy coating according to any one of claims 1 - 5 or the high-entropy alloy coating obtained by the preparation method according to any one of claims 6 - 9 in a coal mine scraper conveyor.

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