A composite material and a method for producing the same, a coating and a method for producing and using the same

Abstract

The application provides a composite material and a preparation method thereof, a coating and a preparation method and application thereof, and the composite material comprises a metal core and a cladding layer cladded on the surface of the metal core, the metal phase comprises Cu, Al and a doping element, the doping element comprises a rare earth element, and the cladding layer is a ceramic cladding layer. The ceramic cladding layer has good lubricity and abradability, the rare earth element in the metal core can purify a base body, modify inclusions, alloy, and reduce the current density of electrochemical corrosion, and improve the high-temperature oxidation resistance and corrosion resistance of the material.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of corrosion-resistant coating material preparation, and relates to a composite material and a preparation method thereof, a coating and a preparation method and application thereof. BACKGROUND

[0002] The seal coating is widely used in the aero-engine, and plays an important role in improving the efficiency, stability and reliability of the overall performance of the aero-engine, reducing fuel consumption and prolonging the service life. The rapid development of the aviation industry puts forward higher and higher requirements for the performance of the aero-engine, and with the continuous deepening of the research and exploration of the ocean, it is urgent to develop a high-temperature corrosion-resistant seal coating for use in the marine environment.

[0003] At present, the abradable seal coating used in the low-pressure compressor is generally AlSi seal coating. Since the maximum working temperature of the new generation of engine internal compressor can reach 600 DEG C, the existing AlSi coating is prone to falling off, chipping, melting and other problems of insufficient temperature resistance at more than 450 DEG C, and the temperature resistance and corrosion resistance of the AlSi seal coating need to be improved.

[0004] The "copper aluminum / graphite and copper aluminum / nickel graphite" coating has good high-temperature resistance and can be used as an abradable seal coating under the working environment temperature of 600 DEG C or below, but its corrosion resistance is poor. Graphite is a good conductor, and graphite has a very high self-corrosion potential and open circuit potential, which is higher than that of general metal materials, but it is preferentially corroded in a salt spray environment, which is very unfavorable to the corrosion resistance of the coating. Boron nitride has good lubricity and abrasion resistance, which can significantly reduce the corrosion current density, and BN can be used to replace graphite as a non-metallic phase.

[0005] The seal coating is mainly prepared by atmospheric plasma spraying, flame spraying and other methods, but due to the limitations of many ceramic phases themselves, their introduction limits the traditional methods such as atmospheric plasma spraying in the preparation of composite coatings. In the preparation process of the coating, BN is seriously lost in the atmospheric plasma spraying process, and is prone to agglomeration, which affects the composition and performance of the final coating.

[0006] Therefore, how to reduce the loss and agglomeration of BN in the atmospheric plasma spraying process, prepare a composite powder with uniform composition, and make the coating prepared from the composite powder have good high-temperature resistance, corrosion resistance and other properties, is a difficult problem to be solved. SUMMARY

[0007] In view of the deficiencies of the prior art, the present application aims to provide a composite material and a preparation method thereof, a coating and a preparation method and application thereof, by coating hexagonal boron nitride on the surface of a copper-aluminum alloy containing rare earth elements, so that the material composition is uniform, a porous and multi-phase structure coating can be obtained, and the corrosion resistance and temperature resistance are improved.

[0008] To achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0009] In a first aspect, the present application provides a composite material, which comprises a metal inner core and a coating layer coated on the outer surface of the metal inner core, the metal inner core comprising Cu, Al and a doping element, the doping element comprising a rare earth element, and the coating layer being a ceramic coating layer.

[0010] The composite material of the present application has a ceramic coating layer coated on the outer surface of the metal inner core, has good lubricity and abradability, and is not conductive, so that the corrosion current density can be significantly reduced to improve the corrosion resistance of the coating. The rare earth element in the metal inner core can purify the matrix, modify inclusions, and alloy, and can reduce the current density of electrochemical corrosion, improve the self-corrosion potential, enhance the corrosion resistance, and improve the high-temperature oxidation resistance and corrosion resistance of the material by adding a low content of rare earth.

[0011] As a preferred technical solution of the present application, the metal inner core comprises a copper-aluminum alloy.

[0012] Preferably, the rare earth element comprises any one or a combination of at least two of Y, Dy, La and Ce, including but not limited to a combination of Y and Dy, a combination of Dy and Ce, a combination of La and Ce, a combination of Dy, La and Ce, a combination of Y, Dy and La, a combination of Y, La and Ce, and the like.

[0013] Preferably, the mass ratio of Cu, Al and the rare earth element in the metal inner core is 100:(8-12):(0.5-4), for example, it can be 100:10:0.5, 100:10:0.8, 100:10:1, 100:10:1.2, 100:10:1.5, 100:10:2, 100:10:2.5, 100:10:3, 100:10:3.3, 100:10:3.5, 100:10:3.8 or 100:10:4, but is not limited to the listed values, and other values not listed in this range are also applicable.

[0014] Preferably, the ceramic coating layer comprises hexagonal boron nitride.

[0015] The coating layer of the present application adopts hexagonal boron nitride, has good lubricity and abradability, and the ceramic coating layer is not conductive, which can reduce the corrosion current density, so as to improve the corrosion resistance of the coating.

[0016] Preferably, the mass ratio of the metal core to the hexagonal boron nitride is 100:(15-20), for example, it can be 100:15, 100:16, 100:17, 100:18, 100:19 or 100:20, but is not limited to the listed values, and other values not listed in the range are also applicable.

[0017] The present application can form a single structure by controlling the content of each metal element and rare earth element in the composite material, so as to further improve the temperature resistance and corrosion resistance.

[0018] In the second aspect, the present application provides a preparation method of the composite material of the first aspect, which comprises:

[0019] (I) mixing Cu powder, Al powder and rare earth powder according to the formula amount to obtain mixed powder;

[0020] (II) heat diffusion treatment is performed on the mixed powder to obtain a metal core;

[0021] (III) coating hexagonal boron nitride on the surface of the metal core to obtain the composite material.

[0022] The present application mixes different metal raw material powders uniformly, and performs high-temperature heat diffusion on them, so that the powders penetrate each other, and then crushing, screening, grading and drying are sequentially performed to obtain a partially alloyed metal core, and finally coating hexagonal boron nitride on the surface of the metal core to obtain a composite material, which realizes the abradability and corrosion resistance of the coating material, has uniform composition, controllable particle size and good fluidity, and can enhance the abradability and corrosion resistance of the material.

[0023] As a preferred technical solution of the present application, in step (I), the mixing is performed by ball milling.

[0024] Preferably, the ball milling is performed in a protective atmosphere.

[0025] Preferably, the rotation speed of the ball mill is 100-400 r / min, for example, it can be 100 r / min, 120 r / min, 150 r / min, 180 r / min, 200 r / min, 230 r / min, 250 r / min, 300 r / min, 320 r / min, 350 r / min, 380 r / min or 400 r / min, but is not limited to the listed values, and other values not listed in the range are also applicable.

[0026] Preferably, the ball milling employs a ball-to-charge ratio of (1-15): 1, such as 1:1, 2:1, 4:1, 5:1, 6:1, 8:1, 10:1, 11:1, 12:1, 13:1, 14:1, or 15:1, but not limited to the listed values, as other values within the range are also applicable.

[0027] Preferably, the ball milling is performed for a time period of 2-8h, such as 2h, 2.5h, 3h, 3.5h, 4h, 5h, 6h, 7h, 7.5h, or 8h, but not limited to the listed values, as other values within the range are also applicable.

[0028] Preferably, the protective atmosphere comprises nitrogen or an inert gas.

[0029] Preferably, the mixing further comprises: after the ball milling, performing a thorough mixing using a mixing device.

[0030] Preferably, the Cu powder, the Al powder, and the rare earth powder each has a purity of >99.9%.

[0031] Preferably, the rare earth powder comprises any one of Y powder, LaF3 powder, Dy powder, and CeF3 powder, or a combination of at least two thereof, including but not limited to a mixture of Y powder and LaF3 powder, a mixture of LaF3 powder and Dy powder, a mixture of Dy powder and CeF3 powder, a mixture of LaF3 powder, Dy powder, and CeF3 powder, and the like.

[0032] Preferably, the Al powder has a particle size of 175-325 mesh, such as 175 mesh, 180 mesh, 190 mesh, 200 mesh, 220 mesh, 235 mesh, 245 mesh, 250 mesh, 265 mesh, 280 mesh, 295 mesh, 300 mesh, 310 mesh, 320 mesh, or 325 mesh, but not limited to the listed values, as other values within the range are also applicable.

[0033] Preferably, the Cu powder has a particle size of 8-15pm, such as 8pm, 9pm, 10pm, 11pm, 12pm, 13pm, 14pm, or 15pm, but not limited to the listed values, as other values within the range are also applicable.

[0034] Preferably, the rare earth powder has a particle size of 15-30pm, such as 15pm, 16pm, 18pm, 20pm, 22pm, 25pm, 26pm, 28pm, or 30pm, but not limited to the listed values, as other values within the range are also applicable.

[0035] As a preferred technical solution of the present application, the mixed powder is subjected to a heat diffusion treatment under a protective gas in step (II).

[0036] Preferably, the heat diffusion treatment is performed at a temperature of 400-800°C, such as 400°C, 430°C, 450°C, 500°C, 550°C, 580°C, 600°C, 650°C, 700°C, 750°C, 780°C or 800°C, but not limited to the listed values, and other values not listed within the range are also applicable.

[0037] Preferably, the heat diffusion treatment is performed for a holding time of 2-6h, such as 2h, 2.5h, 3h, 3.5h, 4h, 4.5h, 5h, 5.5h or 6h, but not limited to the listed values, and other values not listed within the range are also applicable.

[0038] Preferably, the protective gas comprises hydrogen and / or argon.

[0039] Preferably, the hydrogen has a purity of >99.99%.

[0040] Preferably, the preparation method further comprises, after the heat diffusion treatment is completed, sequentially subjecting the mixed powder to a crushing treatment, a sieving classification and a drying treatment.

[0041] Preferably, the drying is vacuum drying.

[0042] Preferably, the metal core has a particle size of 80-350 mesh, such as 80 mesh, 90 mesh, 100 mesh, 120 mesh, 150 mesh, 200 mesh, 220 mesh, 250 mesh, 280 mesh, 300 mesh, 320 mesh, 330 mesh or 350 mesh, but not limited to the listed values, and other values not listed within the range are also applicable.

[0043] As a preferred technical solution of the present application, the coating in step (III) comprises:

[0044] The metal core in step (II) is mixed with the hexagonal boron nitride powder in a formula amount, and a binder is added for mixing and coating.

[0045] Preferably, the binder comprises water glass.

[0046] Preferably, the mass ratio of the metal core, the hexagonal boron nitride powder and the binder is (8-12):(1-4):1, such as 8:1:1, 9:3:1, 10:2:1, 10:3:1, 12:4:1, 8:2:1, 9:4:1 or 8:4:1, but not limited to the listed values, and other values not listed within the range are also applicable.

[0047] In a third aspect, the present application provides a coating, which comprises a substrate layer and an abradable surface layer stacked in sequence, wherein the abradable surface layer comprises the composite material according to the first aspect.

[0048] The coating provided by the present application is a double-layered porous multi-phase structure, and has a compact structure, uniform composition, and good temperature resistance and corrosion resistance.

[0049] In an embodiment of the present application, the substrate layer is a nickel-aluminum alloy layer or a nickel-aluminum-copper alloy layer.

[0050] Preferably, the thickness of the substrate layer is 0.1-0.2 mm, for example, 0.1 mm, 0.12 mm, 0.14 mm, 0.15 mm, 0.16 mm, 0.17 mm, 0.18 mm or 0.2 mm, but not limited to the listed values, and other values not listed in the range are also applicable.

[0051] Preferably, the thickness of the abradable surface layer is 1.0-2.0 mm, for example, 1.0 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm or 2.0 mm, but not limited to the listed values, and other values not listed in the range are also applicable.

[0052] In a fourth aspect, the present application provides a preparation method of the coating according to the third aspect, which comprises:

[0053] (1) providing a substrate sample;

[0054] (2) performing first spraying of alloy raw materials on the surface of the substrate sample to form a substrate layer;

[0055] (3) performing second spraying of the composite material on the surface of the substrate layer to form an abradable surface layer, thereby obtaining the coating.

[0056] In an embodiment of the present application, the preparation method further comprises, in step (1), roughening the surface of the substrate sample.

[0057] Preferably, the roughening treatment comprises sandblasting pretreatment on the surface of the substrate sample to remove the oxide layer on the surface of the substrate sample.

[0058] The present application does not limit the sandblasting pretreatment, and any sandblasting pretreatment method known to those skilled in the art for removing the oxide layer on the surface of the substrate sample can be used. In order to help those skilled in the art better understand the overall technical solution and working process of the present application, the present application exemplarily provides the following specific method for sandblasting pretreatment:

[0059] The surface of the test piece is pretreated by sand blasting, the sand blasting angle of the spray gun and the substrate test piece is adjusted, the high-hardness brown corundum particles are sprayed at high speed to the surface of the substrate test piece under the driving of high-pressure airflow, so that the oxide layer on the surface of the substrate test piece is removed and a rough, clean active surface is formed, so as to increase the bonding area of the coating and the substrate test piece, and the sand blasting angle of the spray gun and the substrate test piece is 60-90°.

[0060] Preferably, the preparation method further comprises: cleaning the substrate test piece before the roughening treatment.

[0061] Preferably, the cleaning comprises: removing oil stains on the surface of the substrate test piece first, and then ultrasonic cleaning.

[0062] It should be noted that after the preparation of the coating is completed, the coating is removed from the surface of the substrate test piece for subsequent use.

[0063] Preferably, the first spraying and the second spraying both adopt atmospheric plasma spraying.

[0064] Preferably, the spraying distance of the first spraying and the second spraying is independently 90-110mm, for example, it can be 90mm, 92mm, 95mm, 98mm, 100mm, 102mm, 105mm, 106mm, 108mm or 110mm, but not only limited to the listed values, other values not listed in this range are also applicable.

[0065] It should be noted that the spraying distance of the first spraying and the second spraying in the present application can be the same or different, and they are independently selected from 90-110mm and do not affect each other.

[0066] Preferably, the working gas of the first spraying and the second spraying respectively independently comprises argon and hydrogen.

[0067] Preferably, the flow rate of the argon is 25-55L / min, for example, it can be 25L / min, 28L / min, 30L / min, 32L / min, 35L / min, 40L / min, 42L / min, 45L / min, 50L / min, 52L / min or 55L / min, but not only limited to the listed values, other values not listed in this range are also applicable.

[0068] The flow rate of the hydrogen gas is 0.5-2.5 L / min, for example, it can be 0.5 L / min, 0.8 L / min, 1.1 L / min, 1.4 L / min, 1.6 L / min, 1.8 L / min, 2 L / min, 2.2 L / min or 2.5 L / min, but not limited to the listed values, and other values not listed in the range are also applicable.

[0069] Preferably, the current of the first spraying and the second spraying is independently 200-500 A, for example, it can be 200 A, 220 A, 250 A, 260 A, 280 A, 300 A, 350 A, 400 A, 430 A, 450 A, 480 A or 500 A, but not limited to the listed values, and other values not listed in the range are also applicable.

[0070] Preferably, the voltage of the first spraying and the second spraying is independently 50-70 V, for example, it can be 50 V, 52 V, 55 V, 56 V, 58 V, 60 V, 63 V, 65 V, 68 V or 70 V, but not limited to the listed values, and other values not listed in the range are also applicable.

[0071] Preferably, the voltage of the second spraying is greater than that of the first spraying.

[0072] It should be noted that the atmospheric plasma spraying is carried out by using an atmospheric plasma spraying device, which is usually realized by a plasma torch, the nozzle and the electrode of the plasma torch are respectively connected to the positive and negative poles of a power supply, a working gas (usually argon, or a mixture of argon and hydrogen) is introduced between the nozzle and the electrode, under certain spraying power conditions, an electric arc is ignited by high-frequency spark to generate plasma, and the raw material powder is sprayed to the surface of the workpiece to be sprayed by using the plasma, so that the surface of the workpiece to be sprayed is chemically and physically changed to form a coating.

[0073] The base layer and the abradable surface layer are prepared by using atmospheric plasma spraying in the present application, which can significantly improve the salt mist resistance and wet heat resistance of the coating, strengthen the comprehensive performance of the coating, and expand the service range of the coating. In addition, the atmospheric plasma spraying method has good adhesion, so that the base layer and the abradable surface are well combined. The hardness of the prepared coating is in the range of 50-70 HR15Y, the porosity content is 15-20%, and the coating also has good anti-erosion ability, which meets the service requirements of the sealing coating, and also has good corrosion resistance.

[0074] In a fifth aspect, the present application provides an application of the coating of the third aspect, and the coating is used for a sealing coating resistant to marine corrosion.

[0075] The coating has good corrosion resistance, can be applied to marine environment, and meets the service requirement of seal coating.

[0076] The numerical range of the present application includes not only the above-mentioned point values, but also any point values between the above-mentioned numerical ranges that are not mentioned, and the specific point values included in the range are not listed in the present application due to the length and the consideration of simplicity.

[0077] Compared with the prior art, the present application has the following beneficial effects:

[0078] The composite material provided by the present application has uniform composition, good fluidity, good spraying effect, low preparation cost, dense coating structure, few defects, uniform ceramic phase distribution, good temperature resistance and corrosion resistance. BRIEF DESCRIPTION OF DRAWINGS

[0079] Figure 1 A microstructure diagram of the composite material prepared in Example 1 of the present application is shown in the figure.

[0080] Figure 2 A microstructure diagram of the CuAlY / hBN composite coating prepared in Example 1 of the present application is shown in the figure.

[0081] Figure 3 A microstructure diagram of the composite material prepared in Example 2 of the present application is shown in the figure.

[0082] Figure 4 A microstructure diagram of the CuAlLaF3 / hBN composite coating prepared in Example 2 of the present application is shown in the figure. DETAILED DESCRIPTION

[0083] It should be understood that the terms "first", "second" and the like are used only for the purpose of description, and should not be understood as indicating or implying relative importance or implying the number of the technical features indicated. Therefore, the features with "first", "second" and the like can explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise stated, the meaning of "a plurality of" is two or more.

[0084] The technical solutions of the present application will be further described below in combination with the drawings and through specific embodiments.

[0085] In one embodiment, the present application provides a composite material, comprising a metal inner core and a cladding layer cladded on the outer surface of the metal inner core, the metal inner core comprising Cu, Al and a doping element, the doping element comprising a rare earth element, and the cladding layer being a ceramic cladding layer. The metal inner core comprises a copper-aluminum alloy. The rare earth element comprises any one or a combination of at least two of Y, Dy, La and Ce. The mass ratio of Cu, Al and the rare earth element in the metal inner core is 100:(8-12):(0.5-4). The ceramic cladding layer comprises hexagonal boron nitride, and the mass ratio of the metal inner core and the hexagonal boron nitride is 100:(15-20).

[0086] In one embodiment, the present application provides a preparation method of the composite material described in one embodiment, the preparation method comprising:

[0087] S1 mixing Cu powder, Al powder and rare earth powder according to the formula, and ball milling under the protection of a protective atmosphere to obtain mixed powder, wherein the mass ratio of Cu, Al and the rare earth powder is 100:(8-12):(0.5-4), the rare earth powder comprises any one or a combination of at least two of Y, Dy, La and Ce, the purity of Cu powder, Al powder and the rare earth powder is >99.9%, the particle size of Al powder is 175-325 mesh, the particle size of Cu powder is 8-15 μm, the particle size of the rare earth powder is 15-30 μm, the rotation speed of ball milling is 100-400 r / min, the ball-to-charge mass ratio is (1-15):1, and the ball milling time is 2-8 h;

[0088] S2 performing heat diffusion treatment on the mixed powder under the protection of a protective atmosphere, the heat diffusion treatment temperature is 400-800 ℃, and the holding time is 2-6 h, so that the powders penetrate each other, and then sequentially performing crushing, screening, grading and vacuum drying, the vacuum drying temperature is 40-60 ℃, and the time is 4-8 h, to obtain a metal inner core with a particle size of 80-350 mesh;

[0089] S3 mixing the metal inner core in step (2) and hexagonal boron nitride powder according to the formula of a mass ratio of the metal inner core and the hexagonal boron nitride of 100:(15-20), and adding water glass for cladding to obtain the composite material.

[0090] In another embodiment, the present application provides a coating layer, comprising a substrate layer and an abradable surface layer which are sequentially stacked, and the abradable surface layer comprises the composite material described in one embodiment. The substrate layer is a nickel-aluminum alloy layer or a nickel-aluminum-copper alloy layer, and the thickness of the substrate layer is 0.1-0.2 mm. The thickness of the abradable surface layer is 1.0-2.0 mm.

[0091] In another embodiment, the present application provides a method for preparing the coating as described in another embodiment, the method comprising:

[0092] (1) providing a substrate, removing oil on the surface of the substrate, and further cleaning the surface of the substrate by ultrasonic cleaning with acetone;

[0093] (2) using a dry sand blasting machine to perform sand blasting pretreatment on the sprayed surface of the substrate, the sand blasting angle of the spray gun and the substrate is 60-90°, the pressure of the air compressor is 0.4 MPa, high-hardness brown corundum particles are sprayed onto the surface of the substrate under the driving of high-pressure airflow to remove the oxide layer on the surface, form a rough and clean active surface, and increase the bonding area of the coating and the substrate;

[0094] (3) using atmospheric plasma spraying method to perform first spraying of alloy raw materials on the surface of the substrate, the process parameters of atmospheric plasma spraying are: voltage 50-70 V, current 200-500 A, argon flow rate 25-55 L / min, hydrogen flow rate 0.5-2.5 L / min, and spraying distance 90-110 mm, to form a base layer;

[0095] (3) using atmospheric plasma spraying method to perform second spraying of composite materials on the surface of the base layer, the process parameters of atmospheric plasma spraying are: voltage 50-70 V, current 300-500 A, argon flow rate 25-55 L / min, hydrogen flow rate 0.5-2.5 L / min, and spraying distance 90-110 mm, to form an abradable surface layer, and obtain the coating with a porous and multiphase structure.

[0096] Example 1

[0097] The present embodiment provides a method for preparing a marine corrosion-resistant sealing coating, specifically comprising the following steps:

[0098] (1) mixing Cu powder, Al powder and Y powder according to a mass ratio of Cu:Al:Y = 100:10:2, and ball milling under the protection of argon to obtain Cu-Al-Y mixed powder;

[0099] The ball milling parameters are: ball milling speed 200 r / min, ball-to-material mass ratio 2:1, ball milling time 6 h, stainless steel balls with sizes of 10 mm, 5 mm and 3 mm are used, and ball milling is performed in a stainless steel tank according to a mass ratio of 1:5:20;

[0100] (2) performing high-temperature thermal diffusion treatment on the mixed powder under the protection of hydrogen with a purity of 99.99%, the treatment temperature is 520℃, the holding time is 6 h, after the holding time ends, cooling to room temperature to obtain the product;

[0101] (3) The product obtained in step (2) is taken out, crushed by a disc crusher, and then sieved to obtain a powder with a particle size of 250 mesh, which is dried at 60°C for 2h under vacuum to obtain a metal core;

[0102] (4) The metal core obtained in step (3) is mixed with the hBN powder according to a mass ratio of the metal core to the hBN of 100:18, and mixed and coated with water glass to obtain a Cu-Al-Y / hBN composite material;

[0103] (5) A TC4 titanium alloy substrate sample is provided, which is sequentially subjected to oil removal and sand blasting, and a CuNi 12 Al2 alloy raw material is sprayed on the surface of the TC4 titanium alloy substrate sample by an atmospheric plasma spraying technique to form a base layer;

[0104] The atmospheric plasma spraying conditions are as follows: an APS-2000K type plasma spraying device is used, the argon flow rate is 30L / min, the hydrogen flow rate is 2L / min, the current is 400A, the voltage is 55V, and the spraying distance is 100mm.

[0105] (6) The composite material obtained in (4) is sprayed on the base layer obtained in (5) by an atmospheric plasma spraying method to form an abradable surface layer, thereby obtaining a Cu-Al-Y / hBN composite coating;

[0106] The atmospheric plasma spraying conditions are as follows: an APS-2000K type plasma spraying device is used, the argon flow rate is 30L / min, the hydrogen flow rate is 2L / min, the current is 400A, the voltage is 60V, and the spraying distance is 100mm.

[0107] The Cu-Al-Y / hBN composite material prepared in this embodiment is tested as follows:

[0108] ① The microstructure of the composite material is observed by a scanning electron microscope, and the results are shown in Figure 1 It can be seen that the composite material is spherical, the powder diameter is small, and the powder diameter is 40-60μm.

[0109] ② The composite material is subjected to XRD phase analysis by an X-ray diffractometer, and it is found that the composite material is not oxidized during the solid-phase alloying and hBN coating processes.

[0110] ③ The bulk density and flowability of the composite material are tested by a powder flowability tester, and it is found that the bulk density of the composite material is 1.01g / cm 3 , the flowability is 85s / 50g, the flowability of the composite material is good, and the spraying property is good.

[0111] ④ CuNi12 Al2underlayer, which has good adhesion, so that it is well combined with the Cu-Al-Y / hBN surface layer, the bonding strength of the Cu-Al-Y / hBN surface layer is greater than 5 MPa measured by a universal testing machine, the hardness is in the range of 50-70 HR15Y measured by a Rockwell hardness tester, and the porosity is about 20% measured by the Archimedes drainage method.

[0112] 5. The microstructure of the prepared Cu-Al-Y / hBN composite coating is observed by a scanning electron microscope, and the results are shown in FIG. 2. Figure 2 As can be seen from FIG. 2, the composite coating has a dense structure and few defects, and the added hBN is uniformly distributed.

[0113] Example 2

[0114] The embodiment provides a preparation method of a marine corrosion-resistant sealing coating, and specifically includes the following steps.

[0115] (1) Cu powder, Al powder and LaF3powder are uniformly mixed according to a mass ratio of Cu:Al:LaF3=100:10:1, and ball milling is performed under the protection of argon to obtain Cu-Al-LaF3mixed powder;

[0116] The ball milling parameters are as follows: the ball milling speed is 400 r / min, the ball-to-material mass ratio is 2:1, the ball milling time is 6 h, stainless steel balls with sizes of 10 mm, 5 mm and 3 mm are used, and ball milling is uniformly performed in a stainless steel tank according to a mass ratio of 1:5:20;

[0117] (2) The mixed powder is subjected to high-temperature thermal diffusion treatment under the protection of hydrogen with a purity of 99.99%, the treatment temperature is 520 ℃, the holding time is 6 h, after the holding is completed, cooling to room temperature to obtain a product;

[0118] (3) The product obtained in step (2) is taken out, broken by a disc-type crusher, and then sieved and graded to obtain a powder with a particle size of 300 mesh, and vacuum drying is performed at 60 ℃ for 2 h to obtain a metal core;

[0119] (4) The metal core obtained in step (3) is mixed with hexagonal boron nitride powder according to a mass ratio of the metal core to the hexagonal boron nitride of 100:18, and mixing and coating are performed by using water glass to obtain a Cu-Al-LaF3 / hBN composite material;

[0120] (5) A TC4 titanium alloy substrate sample is provided, and oil removal and sand blasting are sequentially performed on the TC4 titanium alloy substrate sample, and a CuNi 12 Al2alloy raw material to form a base layer;

[0121] The atmospheric plasma spraying conditions are as follows: using APS-2000K type plasma spraying equipment, argon flow rate is 40 L / min, hydrogen flow rate is 4 L / min, current is 400 A, voltage is 55 V, spraying distance is 100 mm.

[0122] (6) The composite material obtained in (4) is sprayed on the substrate layer obtained in (5) by atmospheric plasma spraying to form an abradable surface layer, thereby obtaining a Cu-Al-LaF3 / hBN composite coating;

[0123] The atmospheric plasma spraying conditions are as follows: using APS-2000K type plasma spraying equipment, argon flow rate is 40 L / min, hydrogen flow rate is 4 L / min, current is 400 A, voltage is 60 V, spraying distance is 100 mm.

[0124] The CuAlLaF3 / hBN composite material prepared in this embodiment is tested as follows:

[0125] ① The microstructure of the composite material is observed by scanning electron microscope, and the results are shown in FIG. 1. Figure 3 It can be seen that the composite material is spheroidal, and the powder diameter is small, being 80-120 μm.

[0126] ② The XRD phase analysis of the composite material is performed by X-ray diffractometer, and it is found that the composite material is not oxidized during the solid phase alloying and hBN coating.

[0127] ③ The bulk density and flowability of the composite material are tested by a powder flowability tester, and it is found that the bulk density of the composite material is 1.23 g / cm 3 , and the flowability is 76 s / 50 g. The composite material has good flowability and spraying property.

[0128] ④ The CuNi 12 Al2 substrate layer is sprayed by atmospheric plasma spraying, and has good adhesion, so that the Cu-Al-LaF3 / hBN surface layer is well combined with the CuNiAl2 substrate layer. The bonding strength of the Cu-Al-LaF3 / hBN surface layer is greater than 5 MPa, the hardness is in the range of 50-70 HR15Y, and the porosity content is about 20% by Archimedes drainage method.

[0129] ⑤ The microstructure of the CuAlY / hBN composite coating prepared is observed by scanning electron microscope, and the results are shown in FIG. 2. Figure 4 It can be seen that the composite coating has dense structure, few defects, and the added hBN is uniformly distributed.

[0130] Example 3

[0131] The embodiment provides a preparation method of a marine corrosion-resistant sealing coating, and specifically comprises the following steps.

[0132] (1) Cu powder, Al powder and CeF3 powder are uniformly mixed according to a mass ratio of Cu:Al:CeF3=100:10:3, and ball milling is carried out under the protection of argon to obtain Cu-Al-CeF3 mixed powder;

[0133] The ball milling parameters are as follows: the ball milling speed is 300 r / min, the ball-to-material mass ratio is 4:1, the ball milling time is 8 h, stainless steel balls with sizes of 10 mm, 5 mm and 3 mm are used, and ball milling and uniform mixing are carried out in a stainless steel tank according to a mass ratio of 1:5:20;

[0134] (2) The mixed powder is subjected to high-temperature thermal diffusion treatment under the protection of hydrogen with a purity of 99.99%, the treatment temperature is 700 DEG C, the holding time is 4 h, after the holding is completed, cooling to room temperature is carried out, and a product is obtained;

[0135] (3) The product obtained in the step (2) is taken out, broken by using a disc-type crusher, and then subjected to screening and grading to obtain powder with a particle size of 100 mesh, vacuum drying is carried out at 60 DEG C for 2 h, and a metal core is obtained;

[0136] (4) The metal core obtained in the step (3) is mixed with hBN powder according to a mass ratio of the metal core to hBN of 100:15, and mixing and coating are carried out by using water glass to obtain a Cu-Al-CeF3 / hBN composite material;

[0137] (5) A TC4 titanium alloy substrate sample is provided, oil removal and sand blasting are sequentially carried out on the TC4 titanium alloy substrate sample, and the surface of the TC4 titanium alloy substrate sample is sprayed with a Ni-Al alloy raw material by using an atmospheric plasma spraying technology to form a base layer;

[0138] The atmospheric plasma spraying conditions are as follows: an APS-2000K type plasma spraying device is used, the argon flow rate is 50 L / min, the hydrogen flow rate is 1 L / min, the current is 400 A, the voltage is 60 V, and the spraying distance is 90 mm.

[0139] (6) The composite material obtained in the step (4) is sprayed on the base layer obtained in the step (5) by using an atmospheric plasma spraying method to form an abradable surface layer, and a Cu-Al-CeF3 / hBN composite coating is obtained;

[0140] The atmospheric plasma spraying conditions are as follows: an APS-2000K type plasma spraying device is used, the argon flow rate is 50 L / min, the hydrogen flow rate is 1 L / min, the current is 400 A, the voltage is 70 V, and the spraying distance is 90 mm.

[0141] The composite material obtained in the embodiment is spherical, has small powder diameter, is not oxidized during solid phase alloying and coating of hBN, and has good fluidity. The Cu-Al-CeF3 / hBN surface layer in the coating has a bonding strength greater than 4 MPa, a hardness in the range of 50-70 HR15Y, and a porosity content of about 18%, and the composite coating has a dense structure, few defects, and uniformly distributed hBN.

[0142] Example 4

[0143] The embodiment provides a preparation method of a marine corrosion-resistant sealing coating, and specifically comprises the following steps:

[0144] (1) Cu powder, Al powder and Dy powder are uniformly mixed according to a mass ratio of Cu:Al:Dy = 100:10:4, ball milling is performed under the protection of argon, and then mixing is performed for 10 hours at 100 RPM by using a mixer to fully mix, to obtain mixed powder of Cu-Al-Dy;

[0145] Ball milling parameters are as follows: a ball milling speed is 200 r / min, a ball-to-material mass ratio is 4:1, a ball milling time is 3 hours, stainless steel balls with sizes of 10 mm, 5 mm and 3 mm are used, and ball milling and uniform mixing are performed in a stainless steel tank according to a mass ratio of 1:5:20;

[0146] (2) The mixed powder is subjected to high-temperature thermal diffusion treatment under the protection of hydrogen with a purity of 99.99%, a treatment temperature is 800 DEG C, a holding time is 2.5 hours, after the holding time ends, cooling is performed to room temperature, and a product is obtained;

[0147] (3) The product obtained in step (2) is taken out, broken by using a disc-type crusher, and then subjected to screening and grading, to obtain powder with a particle size of 150 mesh, and vacuum drying is performed at 60 DEG C for 2 hours, to obtain a metal core;

[0148] (4) The metal core obtained in step (3) is mixed with hexagonal boron nitride powder according to a mass ratio of the metal core to the hexagonal boron nitride of 100:20, and mixing and coating are performed by using water glass, to obtain Cu-Al-Dy / hBN composite material;

[0149] (5) A TC4 titanium alloy substrate sample is provided, oil removal and sand blasting are sequentially performed on the TC4 titanium alloy substrate sample, and CuNi 12 Al2 alloy raw material is sprayed on the surface of the TC4 titanium alloy substrate sample by using atmospheric plasma spraying technology, to form a base layer;

[0150] The atmospheric plasma spraying condition is as follows: an APS-2000K type plasma spraying device is used, an argon flow rate is 50 L / min, a hydrogen flow rate is 1 L / min, a current is 400 A, a voltage is 58 V, and a spraying distance is 90 mm.

[0151] (6) the composite material obtained in (4) is sprayed on the substrate layer obtained in (5) by an atmospheric plasma spraying method to form an abradable surface layer, thereby obtaining a Cu-Al-Dy / hBN composite coating;

[0152] The atmospheric plasma spraying conditions are as follows: an APS-2000K type plasma spraying device is used, the argon flow rate is 50 L / min, the hydrogen flow rate is 2 L / min, the current is 400 A, the voltage is 65 V, and the spraying distance is 108 mm.

[0153] The composite material obtained in this embodiment is spherical, has a small powder diameter, is not oxidized during solid-phase alloying and hBN coating, and has good fluidity. The CuAlY / hBN surface layer in the coating has a bonding strength greater than 6 MPa, a hardness in the range of 50-70 HR15Y, which meets the use requirements, a pore content of about 20%, a dense composite coating structure, few defects, and uniformly distributed hBN.

[0154] Example 5

[0155] The embodiment provides a preparation method of a marine corrosion-resistant sealing coating, and specifically includes the following steps:

[0156] (1) Cu powder, Al powder and Y powder are uniformly mixed according to a mass ratio of Cu:Al:Y = 100:10:3, ball milling is performed under the protection of argon, and then a mixer is used to mix the mixture at 100 RPM for 10 h to fully mix, thereby obtaining Cu-Al-Y mixed powder;

[0157] The ball milling parameters are as follows: the ball milling speed is 150 r / min, the ball-to-material mass ratio is 2:1, the ball milling time is 3 h, stainless steel balls with sizes of 10 mm, 5 mm and 3 mm are used, and ball milling is uniformly performed in a stainless steel tank according to a mass ratio of 1:5:20;

[0158] (2) The mixed powder is subjected to high-temperature thermal diffusion treatment under the protection of hydrogen with a purity of 99.99%, the treatment temperature is 650 DEG C, the holding time is 5 h, after the holding is completed, the product is cooled to room temperature, thereby obtaining the product;

[0159] (3) The product obtained in step (2) is taken out, broken by a disc-type crusher, and then subjected to screening and grading, thereby obtaining powder with a particle size of 325 mesh, and the powder is vacuum dried at 60 DEG C for 2 h, thereby obtaining a metal core;

[0160] (4) The metal core obtained in step (3) and hexagonal boron nitride powder are mixed according to a mass ratio of the metal core to the hexagonal boron nitride of 100:16, and water glass is used for mixing and coating, thereby obtaining a Cu-Al-Y / hBN composite material;

[0161] (5) providing a TC4 titanium alloy substrate sample, sequentially performing oil removal and sand blasting on the substrate sample, and spraying CuNi 12 Al2 alloy raw material to form a base layer;

[0162] The atmospheric plasma spraying conditions are as follows: using an APS-2000K type plasma spraying device, an argon flow rate of 30 L / min, a hydrogen flow rate of 2 L / min, a current of 400 A, a voltage of 50 V, and a spraying distance of 100 mm.

[0163] (6) spraying the composite material obtained in (4) on the base layer obtained in (5) by an atmospheric plasma spraying method to form an abradable surface layer, thereby obtaining a Cu-Al-Y / hBN composite coating;

[0164] The atmospheric plasma spraying conditions are as follows: using an APS-2000K type plasma spraying device, an argon flow rate of 30 L / min, a hydrogen flow rate of 2 L / min, a current of 400 A, a voltage of 55 V, and a spraying distance of 100 mm.

[0165] The composite material obtained in the example is spherical, has a small powder diameter, is not oxidized during solid-phase alloying and hBN coating, and has good fluidity. The Cu-Al-Y / hBN surface layer in the coating has a bonding strength greater than 5 MPa, a hardness in the range of 50-70 HR15Y, a pore content of about 20%, a dense structure, few defects, and uniformly distributed hBN.

[0166] Example 6

[0167] The example provides a preparation method of a marine corrosion-resistant sealing coating, which is different from example 1 in that the mass ratio of Cu powder, Al powder and Y powder is 100:10:5, and the rest of the preparation process and process parameters are the same as those of example 1.

[0168] The composite material obtained in the example is spherical, has a small powder diameter, is not oxidized during solid-phase alloying and hBN coating, and has good fluidity. The Cu-Al-Y / hBN surface layer in the coating has a bonding strength greater than 5 MPa, a hardness in the range of 50-70 HR15Y, a pore content of about 20%, a dense structure, few defects, and uniformly distributed hBN.

[0169] Example 7

[0170] The example provides a preparation method of a marine corrosion-resistant sealing coating, which is different from example 1 in that the doped rare earth powder is a mixture of Y and Dy, the mass ratio of Y to Dy is 2:1, and the rest of the preparation process and process parameters are the same as those of example 1.

[0171] The composite material obtained in this example is spherical, with small powder diameter, and the composite material does not oxidize during solid phase alloying and hBN coating, and has good fluidity. The CuAlYDy / hBN surface layer in the coating has a bonding strength greater than 6 MPa, a hardness in the range of 50-70 HR15Y, a pore content of about 23%, a dense structure, few defects, and uniformly distributed hBN. The high temperature oxidation resistance and salt spray corrosion resistance of the coating are also improved. After 960 hours of salt spray corrosion box corrosion, the bonding strength of the coating is only reduced by 10%, and the performance is improved compared to the performance of pure Y, Dy, La, and Ce.

[0172] Comparative Example 1

[0173] This comparative example provides a preparation method of a marine corrosion resistant sealing coating. The difference from Example 1 is that the metal core is not doped with rare earth elements, and the rest of the preparation process and process parameters are the same as those of Example 1.

[0174] The composite material obtained in this example is spherical, with small powder diameter, and the composite material does not oxidize during solid phase alloying and hBN coating, and has good fluidity. The CuAlYDy / hBN surface layer in the coating has a bonding strength greater than 6 MPa, a hardness in the range of 50-70 HR15Y, a pore content of about 23%, a dense structure, few defects, and uniformly distributed hBN. The high temperature oxidation resistance and salt spray corrosion resistance of the coating are also improved. After 960 hours of salt spray corrosion box corrosion, the bonding strength of the coating is only reduced by 10%, and the performance is improved compared to the performance of pure Y, Dy, La, and Ce.

[0175] The applicant states that the above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto. It should be understood by those skilled in the art that any changes or replacements within the technical scope disclosed by the present application can be easily thought of by those skilled in the art, and all fall within the protection scope and disclosure scope of the present application.

Claims

1. A method for preparing a composite material, characterized in that, The preparation method includes: (I) Mix Cu powder, Al powder and rare earth powder according to the formula to obtain mixed powder; (II) The mixed powder is subjected to thermal diffusion treatment to obtain a metal core; (III) Coating the surface of the metal core with hexagonal boron nitride to obtain the composite material; The rare earth powder in step (I) includes any one or a combination of at least two of Y powder, LaF3 powder, Dy powder and CeF3 powder; The temperature of the heat diffusion treatment in step (II) is 400~800℃; In step (III), the coating process includes mixing the metal core from step (II) with hexagonal boron nitride powder according to the formula amount, and adding a binder for mixing and coating; the mass ratio of the metal core, hexagonal boron nitride powder and binder is (8~12):(1~4):1; The composite material includes a metal core and a coating layer covering the outer surface of the metal core. The metal core includes Cu, Al and doping elements, including rare earth elements. The coating layer is a ceramic coating layer. The mass ratio of Cu, Al and rare earth elements in the metal core is 100:(8~12):(0.5~4).

2. The preparation method according to claim 1, characterized in that, The mass ratio of the metal core to hexagonal boron nitride in the composite material is 100:(15~20).

3. The preparation method according to claim 1, characterized in that, In step (I), the mixing is performed using ball milling.

4. The preparation method according to claim 3, characterized in that, The ball milling was carried out under a protective atmosphere.

5. The preparation method according to claim 3, characterized in that, The ball mill rotates at a speed of 100~400 r / min.

6. The preparation method according to claim 3, characterized in that, The ball mill uses a ball-to-material mass ratio of (1~15):

1.

7. The preparation method according to claim 3, characterized in that, The ball milling time is 2-8 hours.

8. The preparation method according to claim 4, characterized in that, The protective atmosphere includes nitrogen or an inert gas.

9. The preparation method according to claim 3, characterized in that, The mixing process also includes: after the ball milling is completed, a mixing device is used to thoroughly mix the materials.

10. The preparation method according to claim 1, characterized in that, The purity of the Cu powder, Al powder, and rare earth powder is all >99.9%.

11. The preparation method according to claim 1, characterized in that, The particle size of the Al powder is 175~325 mesh.

12. The preparation method according to claim 1, characterized in that, The Cu powder has a particle size of 8~15μm.

13. The preparation method according to claim 1, characterized in that, The particle size of the rare earth powder is 15~30μm.

14. The preparation method according to claim 1, characterized in that, In step (II), the mixed powder is subjected to thermal diffusion treatment under a protective gas.

15. The preparation method according to claim 1, characterized in that, The heat diffusion treatment is maintained for 2 to 6 hours.

16. The preparation method according to claim 14, characterized in that, The protective gas includes hydrogen and / or argon.

17. The preparation method according to claim 16, characterized in that, The purity of the hydrogen gas is >99.99%.

18. The preparation method according to claim 1, characterized in that, The preparation method further includes: after the thermal diffusion treatment is completed, the mixed powder is subjected to crushing, sieving and grading and drying treatment in sequence.

19. The preparation method according to claim 18, characterized in that, The drying process is vacuum drying.

20. The preparation method according to claim 1, characterized in that, The particle size of the metal core is 80~350 mesh.

21. The preparation method according to claim 1, characterized in that, The adhesive includes water glass.

22. A coating, characterized in that, The coating comprises a base layer and an abrasive surface layer stacked sequentially, wherein the abrasive surface layer comprises a composite material obtained by the preparation method according to any one of claims 1 to 21.

23. The coating according to claim 22, characterized in that, The base layer is a nickel-aluminum alloy layer or a nickel-aluminum-copper alloy layer.

24. The coating according to claim 22, characterized in that, The thickness of the base layer is 0.1~0.2mm.

25. The coating according to claim 22, characterized in that, The thickness of the wearable surface layer is 1.0~2.0mm.

26. A method for preparing the coating according to any one of claims 22-25, characterized in that, The preparation method includes: (1) Provide matrix samples; (2) The alloy raw material is first sprayed onto the surface of the substrate sample to form a base layer; (3) A second coating of the composite material is applied to the surface of the base layer to form an abrasive surface layer, thereby obtaining the coating.

27. The preparation method according to claim 26, characterized in that, The preparation method further includes: in step (1), roughening the surface of the substrate sample.

28. The preparation method according to claim 27, characterized in that, The roughening process includes: performing sandblasting pretreatment on the surface of the substrate sample to remove the oxide layer on the surface of the substrate sample.

29. The preparation method according to claim 27, characterized in that, In step (1), the preparation method further includes cleaning the substrate sample before the roughening treatment.

30. The preparation method according to claim 26, characterized in that, Both the first and second spraying processes employ atmospheric plasma spraying.

31. The preparation method according to claim 26, characterized in that, The spraying distance between the first spray and the second spray is independently 90~110mm.

32. The preparation method according to claim 26, characterized in that, The working gases for the first and second spraying processes independently include argon and hydrogen, respectively.

33. The preparation method according to claim 32, characterized in that, The flow rate of argon is 25~55 L / min, and the flow rate of hydrogen is 0.5~2.5 L / min.

34. The preparation method according to claim 26, characterized in that, The current for the first spray and the second spray is independently 200~500A.

35. The preparation method according to claim 26, characterized in that, The voltage for the first spray and the second spray is independently 50~70V.

36. The preparation method according to claim 26, characterized in that, The voltage of the second spraying is greater than the voltage of the first spraying.

37. An application of the coating according to any one of claims 22-25, characterized in that, The coating described is used as a sealing coating resistant to marine corrosion.

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