Anti-wear corrosion-resistant high-entropy alloy composite coating and preparation method thereof

Abstract

The application relates to the field of coating, and discloses an anti-wear and corrosion-resistant high-entropy alloy composite coating and a preparation method thereof. The anti-wear and corrosion-resistant high-entropy alloy composite coating is prepared by depositing functional high-entropy alloy composite powder on the surface of a substrate through laser cladding. The functional high-entropy alloy composite powder comprises high-entropy alloy powder, modified additives and composite ceramic powder. The modified additives are prepared by using urea and titanium tetrachloride as raw materials, growing titanium nitride nanoparticles on the surface of silicon carbide nanowires in situ to form a titanium nitride / silicon carbide nanowire composite material, and then coating the surface of the titanium nitride / silicon carbide nanowire composite material with a layer of titanium dioxide nanoparticles by using tetrabutyl titanate. The composite ceramic powder is prepared by compounding zirconium carbide, niobium carbide, hafnium carbide and tantalum disilicide. The hardness, wear resistance and corrosion resistance of the high-entropy alloy coating are all enhanced by adding the modified additives and the composite ceramic powder.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of coating, and particularly relates to an anti-wear and corrosion-resistant high-entropy alloy composite coating and a preparation method thereof. BACKGROUND

[0002] Coating is one of the most effective and economical methods for protecting metal parts, and coating is usually prepared by processes such as atmospheric plasma spraying, vacuum plasma spraying, electron beam physical vapor deposition and laser cladding. Laser cladding is a low-cost, reliable and convenient coating preparation scheme. High-entropy alloys are widely studied due to their excellent comprehensive performance. High-entropy alloys, also known as multi-component alloys, contain five or more main elements. High-entropy alloy coatings exhibit more unique physical and chemical properties than traditional coatings, such as excellent corrosion resistance, wear resistance and good mechanical strength, and have attracted widespread attention in the field of coatings.

[0003] AlCoCrFeNi is one of the most widely studied high-entropy alloy systems, which has a single-phase BCC structure, high strength and hardness, and excellent high-temperature mechanical properties. However, with the development of the mechanical industry, higher requirements are put forward for materials serving in extreme environments (severe wear and corrosive media), and the surface performance, especially the hardness, wear resistance and corrosion resistance, still needs to be further strengthened and improved. SUMMARY

[0004] To solve the problems mentioned in the background, the purpose of the present application is to provide an anti-wear and corrosion-resistant high-entropy alloy composite coating and a preparation method thereof. The hardness, wear resistance and corrosion resistance of the high-entropy alloy coating are enhanced by adding modified additives and composite ceramic powders to the high-entropy alloy powder as the matrix.

[0005] The purpose of the present application can be achieved by the following technical solutions:

[0006] An anti-wear and corrosion-resistant high-entropy alloy composite coating is deposited on the surface of a substrate by laser cladding using functional high-entropy alloy composite powder. The functional high-entropy alloy composite powder includes the following components by weight: 85-100 parts of high-entropy alloy powder, 1-4 parts of modified additives, and 1.5-3 parts of composite ceramic powder.

[0007] The modified additive is a nano-titanium nitride / silicon carbide nanowire composite material prepared by growing nano-titanium nitride particles in situ on the surface of silicon carbide nanowires using urea and titanium tetrachloride as raw materials, and then coating a layer of nano-titanium dioxide particles on the surface of the nano-titanium nitride / silicon carbide nanowire composite material using tetrabutyl titanate. The composite ceramic powder is prepared by compounding zirconium carbide, niobium carbide, hafnium carbide and tantalum disilicide in a mass ratio.

[0008] Preferably, the high-entropy alloy powder is AlCoCrFeNi.

[0009] Preferably, the preparation method of the modified additive comprises the following steps:

[0010] (1) Take urea and titanium tetrachloride into ethanol, continuously stir until the solution turns light yellow to obtain a precursor solution, then take out the silicon carbide nanowires after impregnation, dry, and then heat treat at 1100-1300 DEG C for 2-3h in a nitrogen atmosphere to prepare a nano-titanium nitride / silicon carbide nanowire composite material;

[0011] (2) Take tetrabutyl titanate and dissolve it in a reactor containing ethanol, then ultrasonically disperse the nano-titanium nitride / silicon carbide nanowire composite material, then place the reactor in a beaker containing distilled water, seal the beaker opening with a plastic film, and then place it in a 75-85 DEG C water bath for 10-12h, wash, filter, dry the reaction product, and finally calcine at 350-400 DEG C for 2-3h to prepare a modified additive.

[0012] Preferably, the diameter of the silicon carbide nanowires in step (1) is 0.1-0.6nm.

[0013] Preferably, the concentration of Ti in the precursor solution in step (1) is 0.05-0.30mmol / mL. 4+

[0014] Preferably, the composite ceramic powder is mixed by zirconium carbide, niobium carbide, hafnium carbide, and tantalum disilicide in a mass ratio.

[0015] Preferably, the particle size of the zirconium carbide, niobium carbide, hafnium carbide, and tantalum disilicide is 1-10um.

[0016] A preparation method of an anti-wear and corrosion-resistant high-entropy alloy composite coating, comprising the following steps: weighing each raw material according to weight parts, mixing the high-entropy alloy powder, the modified additive, and the composite ceramic powder to obtain a functional high-entropy alloy composite powder, then uniformly coating the functional high-entropy alloy composite powder on the surface of the substrate with anhydrous ethanol, introducing high-purity argon gas for protection during the reaction process, and performing laser cladding process to prepare an anti-wear and corrosion-resistant high-entropy alloy composite coating.

[0017] Preferably, the pre-set thickness of the functional high-entropy alloy composite powder is 1-5mm.

[0018] Preferably, the laser cladding process parameters are: scanning speed V=300mm / min, laser power P=3kW, and spot size 2.5mm*11.5mm.

[0019] The beneficial effects of the present application are: ​

[0020] The present application utilizes urea and titanium tetrachloride as raw materials, and nanometer titanium nitride particles grow in situ on the surface of silicon carbide nanowires, the nanometer titanium nitride has high melting point, good chemical stability and excellent oxidation resistance, then a layer of nanometer titanium dioxide particles is coated on the surface of the nanometer titanium nitride / silicon carbide nanowire composite material by using tetrabutyl titanate, and a modified additive is prepared. By introducing nanometer titanium dioxide particles, titanium monoxide and aluminum oxide hard reinforcing phases are precipitated in situ during the laser cladding process, the surface performance of the coating is improved, the hardness and wear resistance of the coating are improved, and the composite ceramic powder composed of zirconium carbide, niobium carbide, hafnium carbide and tantalum disilicide is used as a reinforcing phase. The zirconium carbide is a ceramic material with high hardness and high melting point, has the advantages of high strength, corrosion resistance and not easy to be oxidized in high temperature environment, the melting point of the niobium carbide is as high as 3610℃, and the chemical stability is high, the elastic coefficient of the hafnium carbide is high, the thermal conductivity is good, the thermal expansion coefficient is small, the oxidation of the tantalum disilicide can generate silicon dioxide, and the larger pores in the coating are closed, so that the surface of the coating becomes more dense. The present application uses high-entropy alloy powder as a matrix, mixes zirconium carbide, niobium carbide, hafnium carbide and tantalum disilicide to obtain a composite ceramic powder, and the composite ceramic powder and the modified additive are used as reinforcing phases. The silicon carbide nanowire in the modified additive is a one-dimensional material, and the mixing of the composite ceramic powder and the silicon carbide nanowire can make up for the deficiency of the fracture toughness of the composite ceramic powder, avoid the brittle fracture of the coating caused by stress to a certain extent, and enhance the hardness, wear resistance and corrosion resistance of the high-entropy alloy coating. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present application will be clearly and completely described below in combination with the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0022] The AlCoCrFeNi high-entropy alloy powder in the embodiments and comparative examples of the present application is prepared by vacuum atomization method and produced by Beijing Jiaming Platinum Nonferrous Metal Co., Ltd., with a particle size of 10-50 μm and a purity of ≥99.9%.

[0023] The preparation method of the modified additive in Example 1 comprises the following steps:

[0024] (1) 1.04 g of urea and 0.45 mL of titanium tetrachloride are added to 80 mL of ethanol, and continuous stirring is performed until the solution turns yellow, to obtain a solution containing 0.05 mmol / mL Ti 4+The precursor solution of the titanium nitride / silicon carbide nanowire composite material is prepared by adding the titanium nitride / silicon carbide nanowire composite material into the reactor containing the tetrabutyl titanate solution, and then the titanium nitride / silicon carbide nanowire composite material is ultrasonically dispersed.

[0025] (2) 5 mL of tetrabutyl titanate is dissolved in a reactor containing 30 mL of ethanol, and then the obtained titanium nitride / silicon carbide nanowire composite material is ultrasonically dispersed. Subsequently, the reactor is placed in a beaker containing distilled water, the beaker is sealed with a plastic film, and then placed in a water bath at 80°C for 12 hours. The reaction product is washed, filtered, dried, and finally calcined at 400°C for 2 hours to prepare a modified additive.

[0026] Example 2 A functional high-entropy alloy composite powder includes the following components by weight: 85 parts of AlCoCrFeNi high-entropy alloy powder, 1.5 parts of the modified additive prepared in Example 1, and 1.5 parts of composite ceramic powder, wherein the composite ceramic powder is mixed by zirconium carbide, niobium carbide, hafnium carbide, and tantalum disilicide in a mass ratio.

[0027] A method for preparing a wear-resistant and corrosion-resistant high-entropy alloy composite coating includes the following steps:

[0028] The raw materials are weighed by weight parts, the high-entropy alloy powder, the modified additive, and the composite ceramic powder are mixed thoroughly to obtain a functional high-entropy alloy composite powder, and then the functional high-entropy alloy composite powder is uniformly coated on the surface of a 304 stainless steel substrate with a size of 200x200x5mm 3 , polished with 400-1200 grit sandpaper, and cleaned with alcohol ultrasonic cleaning. The reaction process is carried out under the protection of high-purity argon gas, and the laser cladding process parameters are as follows: scanning speed V=300mm / min, laser power P=3kW, and spot size 2.5mmx11.5mm. A wear-resistant and corrosion-resistant high-entropy alloy composite coating is prepared.

[0029] Example 3 A functional high-entropy alloy composite powder includes the following components by weight: 90 parts of AlCoCrFeNi high-entropy alloy powder, 3 parts of the modified additive prepared in Example 1, and 2 parts of composite ceramic powder, wherein the composite ceramic powder is mixed by zirconium carbide, niobium carbide, hafnium carbide, and tantalum disilicide in a mass ratio.

[0030] A method for preparing a wear-resistant and corrosion-resistant high-entropy alloy composite coating is the same as that in Example 2.

[0031] Example 4 A functional high-entropy alloy composite powder comprises the following components by weight: 95 parts of AlCoCrFeNi high-entropy alloy powder, 4 parts of the modified additive prepared in Example 1, and 2.5 parts of composite ceramic powder, wherein the composite ceramic powder is mixed by zirconium carbide, niobium carbide, hafnium carbide, and tantalum disilicide in a mass ratio.

[0032] A method for preparing a wear-resistant and corrosion-resistant high-entropy alloy composite coating is the same as that in Example 2.

[0033] Comparative Example 1 A functional high-entropy alloy composite powder comprises the following components by weight: 95 parts of AlCoCrFeNi high-entropy alloy powder, 4 parts of the nano-titanium nitride / silicon carbide nanowire composite material prepared in Example 1, and 2.5 parts of composite ceramic powder, wherein the composite ceramic powder is mixed by zirconium carbide, niobium carbide, hafnium carbide, and tantalum disilicide in a mass ratio.

[0034] A method for preparing a wear-resistant and corrosion-resistant high-entropy alloy composite coating is the same as that in Example 2, except that the modified additive is replaced by an equal amount of nano-titanium nitride / silicon carbide nanowire composite material, and the remaining components and steps are the same.

[0035] Comparative Example 2 A functional high-entropy alloy composite powder comprises the following components by weight: 95 parts of AlCoCrFeNi high-entropy alloy powder, and 2.5 parts of composite ceramic powder, wherein the composite ceramic powder is mixed by zirconium carbide, niobium carbide, hafnium carbide, and tantalum disilicide in a mass ratio.

[0036] A method for preparing a wear-resistant and corrosion-resistant high-entropy alloy composite coating is the same as that in Example 2, except that no modified additive is added, and the remaining components and steps are the same.

[0037] Comparative Example 3 A functional high-entropy alloy composite powder comprises the following components by weight: 95 parts of AlCoCrFeNi high-entropy alloy powder, and 4 parts of the modified additive prepared in Example 1.

[0038] A method for preparing a wear-resistant and corrosion-resistant high-entropy alloy composite coating is the same as that in Example 2, except that no composite ceramic powder is added, and the remaining components and steps are the same.

[0039] Performance detection:

[0040] The high-entropy alloy composite coating prepared in Examples 2-4 and Comparative Examples 1-3 is subjected to performance detection: the microhardness of the coating is measured by using a microhardness tester (MCS-1000); the tribological performance of the coating is detected by using a reciprocating friction and wear tester, an Al2O3 grinding ball with a diameter of 5 mm is selected as the counter material, the reciprocating stroke length is 5 mm, the frequency is 2 Hz, the load is 5 N, and the test time is 60 min; the electrochemical corrosion experiment is detected according to GB / T 40299-2021; the impact resistance is detected according to GB / T 2423.5-2019, and the data results are shown in Table 1.

[0041] Table 1: Performance detection results of samples

[0042]

[0043] As can be seen from the data in Table 1, the high-entropy alloy composite coating prepared in Examples 2-4 has high hardness, good wear resistance, corrosion resistance and impact resistance. In Comparative Example 1, the modified additive is replaced by an equal amount of nano-titanium nitride / silicon carbide nanowire composite material, the measured hardness is lower than that of Examples 2-4, the friction coefficient and the wear loss weight are larger than those of Examples 2-4, indicating that the introduction of nano-titanium dioxide particles can improve the hardness and wear resistance of the coating. In Comparative Example 2, no modified additive component is added, and in Comparative Example 3, no composite ceramic powder component is added, the hardness of Comparative Examples 2-3 is lower than that of Example 2-4, the friction coefficient, wear loss weight and corrosion current density are larger than those of Example 2-4, indicating that the addition of the modified additive component and the composite ceramic powder component improves the hardness, wear resistance and corrosion resistance of the coating to some extent, and the impact work of Comparative Example 2 is lower than that of Example 2-4 and Comparative Examples 1 and 3, indicating that the addition of nano-titanium nitride / silicon carbide nanowire composite material can improve the impact resistance of the coating.

[0044] In the description of the present specification, the description referring to the terms "one embodiment", "an example", "a specific example" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0045] The basic principles, main features and advantages of the present application are shown and described above. It should be understood by those skilled in the art that the present application is not limited by the above examples, and the above examples and descriptions in the specification are only illustrative of the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application.

Claims

1. A wear resistant corrosion resistant high entropy alloy composite coating, characterized in that, The functional high-entropy alloy composite powder is deposited on the surface of a substrate by laser cladding, and the functional high-entropy alloy composite powder comprises the following components by weight: 85-100 parts of high-entropy alloy powder, 1-4 parts of modified additive, and 1.5-3 parts of composite ceramic powder. The modified additive is a nano-titanium nitride / silicon carbide nanowire composite material prepared by growing titanium nitride nanoparticles in situ on the surface of silicon carbide nanowires using urea and titanium tetrachloride as raw materials, and then coating a layer of nano-titanium dioxide particles on the surface of the nano-titanium nitride / silicon carbide nanowire composite material using tetrabutyl titanate; and the composite ceramic powder is prepared by compounding zirconium carbide, niobium carbide, hafnium carbide, and tantalum disilicide in a mass ratio.

2. The anti-wear corrosion resistant high-entropy alloy composite coating according to claim 1, wherein, The high-entropy alloy powder is AlCoCrFeNi.

3. The anti-wear corrosion resistant high-entropy alloy composite coating of claim 1, wherein, The preparation method of the modified additive comprises the following steps: (1) urea and titanium tetrachloride are added to ethanol, and continuous stirring is performed until the solution turns yellow, to obtain a precursor solution, then the silicon carbide nanowires are immersed and dried, and then the nanowire is placed in a nitrogen atmosphere at 1100-1300°C for 2-3h for heat treatment, to prepare a nano-titanium nitride / silicon carbide nanowire composite material; (2) tetrabutyl titanate is dissolved in a reactor containing ethanol, then the nano-titanium nitride / silicon carbide nanowire composite material is ultrasonically dispersed, then the reactor is placed in a beaker containing distilled water, the beaker is sealed with a plastic film and placed in a 75-85°C water bath for 10-12h, and the reaction product is washed, filtered, dried, and finally calcined at 350-400°C for 2-3h, to prepare the modified additive.

4. The anti-wear corrosion resistant high-entropy alloy composite coating of claim 3, wherein, The diameter of the silicon carbide nanowires in step (1) is 0.1-0.6nm.

5. The wear-resistant corrosion-resistant high-entropy alloy composite coating of claim 3, wherein, The step (1) precursor solution has a Ti concentration of 0.05-0.30 mmol / mL. 4+ The concentration is 0.05-0.30 mmol / mL.

6. The wear-resistant corrosion-resistant high-entropy alloy composite coating of claim 1, wherein, The particle size of the zirconium carbide, niobium carbide, hafnium carbide, and tantalum disilicide is 1-10μm.

7. A method for preparing the anti-wear and corrosion-resistant high-entropy alloy composite coating according to any one of claims 1-6, characterized in that, The method comprises the following steps: weighing each raw material by weight, mixing the high-entropy alloy powder, the modified additive, and the composite ceramic powder to obtain a functional high-entropy alloy composite powder, then uniformly coating the functional high-entropy alloy composite powder on the surface of the substrate with anhydrous ethanol, introducing high-purity argon gas for protection during the reaction, and performing laser cladding process to prepare an anti-wear and corrosion-resistant high-entropy alloy composite coating.

8. The method of claim 7, wherein the method further comprises: The pre-set thickness of the functional high-entropy alloy composite powder is 1-5mm.

9. The method of claim 7, wherein the method further comprises: The laser cladding process parameters are: scanning speed V=300mm / min, laser power P=3kW, and spot size 2.5mm×11.5mm.

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