A nickel-based coating, its preparation method and application

Abstract

This invention belongs to the field of metal coating technology and discloses a nickel-based coating, its preparation method, and its application. The preparation method of the nickel-based coating includes the following steps: using a nickel-based alloy as raw material, flame spraying is performed on the surface of a substrate to obtain a preliminary nickel-based coating; the preliminary nickel-based coating is remelted by laser heating to obtain a final nickel-based coating; wherein the nickel-based alloy is Ni-20Cr-10TiC. This invention selects a specific Ni-20Cr-10TiC nickel-based alloy as raw material and combines flame spraying and laser remelting processes. The laser remelting process significantly optimizes the microstructure of the nickel-based coating, greatly reduces porosity to block the penetration of corrosive media, and enhances the bonding efficiency between the coating and the substrate. This enables the nickel-based coating to stably adapt to harsh working conditions such as high temperature and strong corrosion, promoting the expansion of nickel-based coatings in high-end industrial applications.

Description

Technical Field

[0001] This invention belongs to the field of metal coating technology, and specifically relates to a nickel-based coating, its preparation method, and its application. Background Technology

[0002] Nickel-based coatings, due to their excellent high-temperature stability, chemical corrosion resistance, and wear resistance, have become key surface materials for extending the service life of substrates in industrial fields. They are widely used in high-temperature wear parts (such as turbine blades) and components subjected to highly corrosive conditions (such as the inner walls of chemical reactors). Currently, the mainstream process for preparing nickel-based coatings in industry is flame spraying technology. This technology heats the nickel-based coating material to a molten state using a flame, causing the molten particles to impact the substrate surface at high speed and accumulate to form a coating. It has advantages such as low equipment cost, simple operation, and the ability to prepare large-area coatings, and can be used to prepare coatings for various metal, alloy, and ceramic substrates.

[0003] However, nickel-based coatings prepared by traditional flame spraying processes suffer from two major defects that severely limit their application under harsh conditions: First, the coating has high porosity. During flame spraying, molten nickel particles rapidly cool and solidify after impacting the substrate, making it difficult for the particles to bond completely and densely. This results in numerous interconnected or closed pores within the coating. These pores easily become channels for corrosive media (such as acid and alkali solutions, and high-temperature oxidizing gases) to penetrate, accelerating substrate corrosion and reducing the coating's load-bearing capacity, thus shortening its service life. Second, the bonding strength between the coating and the substrate is low. The bonding between the flame-sprayed coating and the substrate is mainly mechanical, lacking a strong metallurgical bond. Under vibration, impact, or high-temperature cyclic loading, the coating is prone to peeling and cracking, failing to meet the reliability requirements of heavy machinery, aerospace, and other fields.

[0004] In the existing exploration of technologies to improve the performance of nickel-based coatings, even with post-treatment using hot processing methods such as laser remelting, there are still obvious limitations: On the one hand, the selection of spraying raw materials lacks specificity. Existing technologies mostly use pure nickel or conventional nickel-chromium alloys as spraying raw materials. The composition design of such raw materials is not matched with the hot processing characteristics. After treatment, the coating is prone to problems such as coarse grains and uneven precipitation of reinforcing phases (such as carbides and borides), resulting in limited improvement in hardness and wear resistance. On the other hand, for nickel-based alloys containing reinforcing phases (such as nickel-based alloys containing TiC), existing technologies have not formed a suitable preparation system. The TiC phase is prone to burn-off or agglomeration under the high temperature environment of flame spraying, making it difficult to achieve uniform dispersion during subsequent hot processing. This fails to fully utilize the dispersion strengthening effect of the TiC phase and still cannot solve the core problems of poor coating density and low bonding strength. Summary of the Invention

[0005] The present invention aims to improve at least one technical problem in the prior art.

[0006] The first aspect of this invention provides a method for preparing a nickel-based coating, comprising the following steps:

[0007] A preliminary nickel-based coating is obtained by flame spraying on the surface of a substrate using a nickel-based alloy as the raw material.

[0008] The initial nickel-based coating is remelted by laser heating to obtain a nickel-based coating.

[0009] The nickel-based alloy is Ni-20Cr-10TiC, and the nickel-based alloy is in the form of wire with an average diameter of 1.0mm-1.6mm.

[0010] The temperature of the flame spraying is 800℃-1200℃, and the distance of the flame spraying is 150mm-250mm;

[0011] The scanning speed of the laser beam used for laser heating is 100mm / s-200mm / s.

[0012] Furthermore, the conveying speed of the nickel-based alloy is 3m / min-6m / min.

[0013] Furthermore, the power of the laser heating is 1000W-2000W, and the angle between the laser beam of the laser heating and the surface of the preliminary nickel-based coating is 45°-60°.

[0014] Furthermore, the moving speed of the flame spraying gun is 100mm / s-200mm / s.

[0015] The second aspect of the present invention provides the application of the above-described method for preparing nickel-based coatings in the manufacture of high-temperature wear parts.

[0016] A third aspect of the present invention provides a nickel-based coating, wherein the nickel-based coating is prepared according to the above-described preparation method, and the thickness of the nickel-based coating is 100 μm-500 μm.

[0017] A third aspect of the present invention provides the application of the above-mentioned nickel-based coating as a protective layer on the surface of high-temperature wear parts.

[0018] The beneficial effects of this invention are as follows: This invention selects a specific Ni-20Cr-10TiC nickel-based alloy as raw material and combines it with flame spraying and laser remelting processes. The laser remelting process significantly optimizes the microstructure of the nickel-based coating, greatly reduces porosity to block the penetration of corrosive media, and enhances the bonding efficiency between the coating and the substrate. This enables the nickel-based coating to stably adapt to harsh working conditions such as high temperature and strong corrosion, and promotes the expansion of nickel-based coatings in high-end industrial applications. Attached Figure Description

[0019] Figure 1The image shows the microstructure of the nickel-based coating obtained in Example 1.

[0020] Figure 2 This is a microstructure diagram of the nickel-based coating obtained in Comparative Example 2. Detailed Implementation

[0021] The present invention will be further described below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the description of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0022] This embodiment provides a method for preparing a nickel-based coating, including the following steps:

[0023] A preliminary nickel-based coating is obtained by flame spraying on the surface of a substrate using a nickel-based alloy as the raw material.

[0024] The initial nickel-based coating is remelted by laser heating to obtain a nickel-based coating.

[0025] The nickel-based alloy is Ni-20Cr-10TiC, and the nickel-based alloy is in the form of wire with an average diameter of 1.0mm-1.6mm.

[0026] The temperature of the flame spraying is 800℃-1200℃, and the distance of the flame spraying is 150mm-250mm;

[0027] The scanning speed of the laser beam used for laser heating is 100mm / s-200mm / s.

[0028] The core of the nickel-based coating preparation method provided in this embodiment lies in solving the problems of poor density, insufficient hardness, and weak adaptability to comprehensive working conditions of traditional nickel-based coatings by using nickel-based alloy raw materials with specific compositions and appropriate process combinations (flame spraying and laser remelting).

[0029] For raw material selection, a nickel-based alloy with a composition of Ni-20Cr-10TiC (mass fraction) is chosen as the spraying material. Ni, as the matrix element, can give the alloy good toughness, ensuring that the subsequent coating has high hardness and high temperature stability, while not being prone to cracking or peeling due to excessive brittleness. It can withstand a certain impact load and is suitable for industrial conditions that may be subject to impact. The mass fraction of Cr reaches 20%, which allows the alloy to form a dense oxide film at high temperatures, effectively preventing further oxidation of the coating and substrate, improving the coating's oxidation resistance and high temperature strength, and meeting the performance requirements of the coating under high temperature conditions. The mass fraction of TiC is 10%. Since TiC itself has extremely high hardness and excellent wear resistance, its uniform distribution in the nickel-based alloy can significantly improve the overall hardness and wear resistance of the coating.

[0030] In the preparation of the nickel-based coating, the aforementioned nickel-based alloy is first sprayed onto the substrate surface using flame spraying technology to form a preliminary nickel-based coating. Flame spraying technology has the advantages of simple equipment operation and the ability to prepare large-area coatings. It enables the nickel-based alloy wire to be rapidly heated to a molten state under the action of a flame. The molten alloy particles impact the substrate surface at high speed and accumulate to form a shape, laying the foundation for obtaining a uniform coating in the subsequent process. At the same time, this step can be adapted to substrates of different materials and shapes, improving the industrial applicability of the method. Next, the initially formed nickel-based coating (preliminary nickel-based coating) is remelted using laser heating technology. This step is crucial for achieving a leap in coating performance. Laser heating features high energy density and strong controllability of heat input, enabling selective and precise secondary melting of the preliminary nickel-based coating. During the melting process, the pores formed by particle accumulation inside the preliminary nickel-based coating are fully filled, significantly improving the coating's density and preventing corrosive media from penetrating into the substrate through the pores. Simultaneously, laser remelting promotes the optimization of the coating's internal microstructure, allowing TiC particles to be more uniformly dispersed in the nickel-based matrix, further enhancing their dispersion strengthening effect and ensuring a stable improvement in coating hardness and wear resistance. Furthermore, the oxide film structure formed by Cr elements during remelting is more stable, further consolidating the coating's high-temperature performance. Ultimately, the prepared nickel-based coating possesses high density, high hardness, excellent wear resistance, high-temperature oxidation resistance, and good toughness.

[0031] Choosing wire as the raw material form for nickel-based alloys is more suitable for the "continuous feeding-melting-deposition" process logic of flame spraying compared to powder forms. The wire can be continuously and stably conveyed through the wire feeding mechanism, improving the stability of flame spraying.

[0032] If the average diameter of the wire is too small (less than 1.0 mm), the thin-diameter wire may melt rapidly in the flame during flame spraying, leading to unstable wire feeding, difficulty in forming a uniform coating, uneven coating thickness, and consequently affecting the subsequent laser remelting effect, ultimately reducing the overall performance of the nickel-based coating. If the average diameter of the wire is too large (greater than 1.6 mm), the larger diameter wire will not melt completely in the flame, resulting in unmelted particles being trapped in the coating, increasing the coating's porosity. During subsequent laser remelting, these unmelted particles will also affect the uniformity of laser remelting, reducing the bonding strength between the nickel-based coating and the substrate.

[0033] If the flame spraying temperature is below 800℃, the heat released by the flame cannot meet the requirement of complete melting of the nickel-based alloy. The unmelted nickel-based alloy will deposit with the molten droplets, increasing the porosity of the initial nickel-based coating. Furthermore, the bonding between the unmelted nickel-based alloy and the substrate is only mechanical interlocking, affecting the bonding strength of the initial nickel-based coating. If the temperature is above 1200℃, the excessively high flame temperature will cause excessive burning of low-melting-point elements in the nickel-based alloy, causing the alloy composition to deviate from the design ratio, damaging the toughness and high-temperature stability of the coating. At the same time, the high temperature will cause the surface temperature of the substrate to rise sharply through heat conduction, making the substrate prone to deformation. If the flame spraying distance is less than 150mm, the high-temperature core area of ​​the flame is in direct contact with the substrate surface. The substrate will continuously absorb high-temperature heat, leading to surface overheating and substrate deformation. At the same time, the coating is continuously heated in the high-temperature area, which can easily generate internal stress due to uneven thermal expansion, resulting in defects such as pores and cracks. If the flame spraying distance is greater than 250mm, the molten particles formed after the nickel-based alloy melts will lose too much heat during flight and will not be able to fully melt when they reach the substrate surface. This will reduce the bonding strength of the initial nickel-based coating and increase its porosity.

[0034] If the scanning speed of the laser beam is greater than 200 mm / s, the laser beam's action time on the unit area of ​​the initial nickel-based coating is too short, resulting in insufficient melting of the initial nickel-based coating and affecting the laser remelting effect. If the scanning speed of the laser beam is less than 100 mm / s, the laser action time is too long, which will cause excessive growth of grains inside the initial nickel-based coating, thereby reducing the coating's toughness and wear resistance.

[0035] Furthermore, the conveying speed of the nickel-based alloy is 3m / min-6m / min.

[0036] In flame spraying, nickel-based alloys need to be fully melted in the flame before impacting the substrate in the form of molten particles and depositing to form a film. The conveying speed directly determines the heating time and melting degree of the alloy in the flame: if the conveying speed of the nickel-based alloy is greater than 6 m / min, the excessively fast feeding rate will significantly shorten the residence time of the alloy wire in the flame area, and the heat released by the flame cannot be fully transferred to the inside of the wire, resulting in the wire being difficult to fully melt, ultimately affecting the overall performance of the nickel-based coating; if the conveying speed of the nickel-based alloy is less than 3 m / min, the excessively slow feeding rate will result in too little molten alloy deposited on the surface of the substrate per unit time, and even if the spraying time is extended, it will be difficult to form a preliminary nickel-based coating with uniform thickness that meets the usage requirements.

[0037] Furthermore, the power of the laser heating is 1000W-2000W, and the angle between the laser beam of the laser heating and the surface of the preliminary nickel-based coating is 45°-60°.

[0038] If the laser heating power is below 1000W, the laser energy density is insufficient to melt the initial coating, resulting in unfilled pores, high porosity, and ineffective improvement in properties such as hardness and wear resistance. If the laser heating power is above 2000W, the excessive energy density will cause the initial nickel-based coating to overheat instantly, leading to cracks, deformation, or even burning through the substrate. If the angle between the laser beam and the surface of the initial nickel-based coating is less than 45°, the incident angle is too small, resulting in a narrow distribution of laser energy on the surface, which can easily cause localized over-melting and defects such as cracks. If the angle between the laser beam and the surface of the initial nickel-based coating is greater than 60°, the scattering of laser energy on the surface increases, reducing energy utilization and making it impossible to effectively remelt and densify the initial nickel-based coating.

[0039] Furthermore, the moving speed of the flame spraying gun is 100mm / s-200mm / s.

[0040] If the spray gun's moving speed is greater than 200 mm / s, the residence time of the spray gun on the substrate per unit area is too short, resulting in uneven thickness of the initial nickel-based coating and potentially weak adhesion between the initial nickel-based coating and the substrate. If the spray gun's moving speed is less than 100 mm / s, the residence time on the substrate per unit area is too long, resulting in too many molten particles deposited per unit area, forming an excessively thick initial coating, which is prone to stress concentration and has low production efficiency.

[0041] In the specific implementation of this nickel-based coating preparation method, the flame spraying parameters (the conveying speed of the nickel-based alloy, the flame spraying temperature, the flame spraying distance, and the moving speed of the flame spraying gun) and the laser remelting parameters (the laser heating power, the angle between the laser beam and the surface of the initial nickel-based coating, and the scanning speed of the laser beam) work in tandem. For example, when the thickness and quality of the initial nickel-based coating formed by flame spraying are affected by the moving speed of the spray gun and the conveying speed of the nickel-based alloy, the subsequent laser heating power and the scanning speed of the laser beam need to be matched accordingly. If the initial nickel-based coating formed by flame spraying is thick, the laser heating power needs to be appropriately increased, and the scanning speed of the beam needs to be appropriately decreased to ensure that the initial nickel-based coating is fully remelted; and vice versa.

[0042] Example 1

[0043] A method for preparing a nickel-based coating includes the following steps:

[0044] A preliminary nickel-based coating is obtained by flame spraying on the surface of a substrate using a nickel-based alloy as the raw material.

[0045] The initial nickel-based coating is remelted by laser heating to obtain a nickel-based coating.

[0046] The nickel-based alloy is Ni-20Cr-10TiC, and the nickel-based alloy is in the form of wire with an average diameter of 1.2 mm. The conveying speed of the nickel-based alloy is 4 m / min. The flame spraying temperature is 1000℃, the flame spraying distance is 200 mm, and the moving speed of the flame spraying gun is 150 mm / s. The laser heating power is 1500 W, the angle between the laser beam and the surface of the preliminary nickel-based coating is 50°, and the scanning speed of the laser beam is 150 mm / s.

[0047] The thickness of the nickel-based coating obtained in Example 1 was 100 μm.

[0048] The microstructure of the nickel-based coating obtained in Example 1 is shown in the figure below. Figure 1 As shown, it has a dense coating microstructure.

[0049] Example 2

[0050] A method for preparing a nickel-based coating includes the following steps:

[0051] A preliminary nickel-based coating is obtained by flame spraying on the surface of a substrate using a nickel-based alloy as the raw material.

[0052] The initial nickel-based coating is remelted by laser heating to obtain a nickel-based coating.

[0053] The nickel-based alloy is Ni-20Cr-10TiC, and the nickel-based alloy is in the form of wire with an average diameter of 1.6 mm. The conveying speed of the nickel-based alloy is 6 m / min. The flame spraying temperature is 1200℃, the flame spraying distance is 250 mm, and the moving speed of the flame spraying gun is 200 mm / s. The laser heating power is 2000 W, the angle between the laser beam and the surface of the preliminary nickel-based coating is 60°, and the scanning speed of the laser beam is 200 mm / s.

[0054] The thickness of the nickel-based coating obtained in Example 2 was 300 μm.

[0055] Example 3

[0056] A method for preparing a nickel-based coating includes the following steps:

[0057] A preliminary nickel-based coating is obtained by flame spraying on the surface of a substrate using a nickel-based alloy as the raw material.

[0058] The initial nickel-based coating is remelted by laser heating to obtain a nickel-based coating.

[0059] The nickel-based alloy is Ni-20Cr-10TiC, and the nickel-based alloy is in the form of wire with an average diameter of 1.4 mm. The conveying speed of the nickel-based alloy is 5 m / min. The flame spraying temperature is 1050℃, the flame spraying distance is 220 mm, and the moving speed of the flame spraying gun is 180 mm / s. The laser heating power is 1800 W, the angle between the laser beam and the surface of the preliminary nickel-based coating is 55°, and the scanning speed of the laser beam is 180 mm / s.

[0060] The thickness of the nickel-based coating obtained in Example 3 was 500 μm.

[0061] Example 4

[0062] A method for preparing a nickel-based coating includes the following steps:

[0063] A preliminary nickel-based coating is obtained by flame spraying on the surface of a substrate using a nickel-based alloy as the raw material.

[0064] The initial nickel-based coating is remelted by laser heating to obtain a nickel-based coating.

[0065] The nickel-based alloy is Ni-20Cr-10TiC, and the nickel-based alloy is in the form of wire with an average diameter of 1.3 mm. The conveying speed of the nickel-based alloy is 5.5 m / min. The flame spraying temperature is 1100℃, the flame spraying distance is 240 mm, and the moving speed of the flame spraying gun is 190 mm / s. The laser heating power is 1700 W, the angle between the laser beam and the surface of the preliminary nickel-based coating is 58°, and the scanning speed of the laser beam is 190 mm / s.

[0066] The thickness of the nickel-based coating obtained in Example 4 was 300 μm.

[0067] Example 5

[0068] A method for preparing a nickel-based coating includes the following steps:

[0069] A preliminary nickel-based coating is obtained by flame spraying on the surface of a substrate using a nickel-based alloy as the raw material.

[0070] The initial nickel-based coating is remelted by laser heating to obtain a nickel-based coating.

[0071] The nickel-based alloy is Ni-20Cr-10TiC, and the nickel-based alloy is in the form of wire with an average diameter of 1.5 mm. The conveying speed of the nickel-based alloy is 4.5 m / min. The flame spraying temperature is 950℃, the flame spraying distance is 230 mm, and the moving speed of the flame spraying gun is 170 mm / s. The laser heating power is 1600 W, the angle between the laser beam and the surface of the preliminary nickel-based coating is 52°, and the scanning speed of the laser beam is 170 mm / s.

[0072] The nickel-based coating obtained in Example 5 has a thickness of 100 μm.

[0073] Comparative Example 1

[0074] A method for preparing a nickel-based coating includes the following steps:

[0075] Nickel-based alloys are used as raw materials, and flame spraying is performed on the surface of the substrate to obtain a nickel-based coating.

[0076] The nickel-based alloy is Ni-20Cr-10TiC, and the nickel-based alloy is in the form of wire with an average diameter of 1.2 mm. The conveying speed of the nickel-based alloy is 4 m / min. The flame spraying temperature is 1000℃, the flame spraying distance is 200 mm, and the moving speed of the flame spraying gun is 150 mm / s.

[0077] The thickness of the nickel-based coating obtained in Comparative Example 1 was 100 μm.

[0078] Comparative Example 2

[0079] A method for preparing a nickel-based coating includes the following steps:

[0080] Nickel-based alloys are used as raw materials, and flame spraying is performed on the surface of the substrate to obtain a nickel-based coating.

[0081] The nickel-based alloy is Ni-20Cr-10TiC, and the nickel-based alloy is in the form of wire with an average diameter of 1.6 mm. The conveying speed of the nickel-based alloy is 6 m / min. The flame spraying temperature is 1200℃, the flame spraying distance is 250 mm, and the moving speed of the flame spraying gun is 200 mm / s.

[0082] The thickness of the nickel-based coating obtained in Comparative Example 2 was 500 μm.

[0083] The microstructure of the nickel-based coating obtained in Comparative Example 2 is shown in the figure. Figure 2 As shown, the coating microstructure is non-dense.

[0084] Comparative Example 3

[0085] A method for preparing a nickel-based coating includes the following steps:

[0086] Nickel-based alloys are used as raw materials, and flame spraying is performed on the surface of the substrate to obtain a nickel-based coating.

[0087] The nickel-based alloy is Ni-20Cr-10TiC, and the nickel-based alloy is in the form of wire with an average diameter of 1.4 mm. The conveying speed of the nickel-based alloy is 5 m / min. The flame spraying temperature is 1050℃, the flame spraying distance is 220 mm, and the moving speed of the flame spraying gun is 180 mm / s.

[0088] The thickness of the nickel-based coating obtained in Comparative Example 3 was 80 μm.

[0089] Comparative Example 4

[0090] A method for preparing a nickel-based coating includes the following steps:

[0091] A preliminary nickel-based coating is obtained by flame spraying on the surface of a substrate using a nickel-based alloy as the raw material.

[0092] The initial nickel-based coating is remelted by laser heating to obtain a nickel-based coating.

[0093] The nickel-based alloy is Ni-20Cr-10TiC, and the nickel-based alloy is in the form of wire with an average diameter of 1.8 mm. The conveying speed of the nickel-based alloy is 7 m / min. The flame spraying temperature is 1300℃, the flame spraying distance is 280 mm, and the moving speed of the flame spraying gun is 80 mm / s. The laser heating power is 2200 W, the angle between the laser beam and the surface of the preliminary nickel-based coating is 45°, and the scanning speed of the laser beam is 80 mm / s.

[0094] The thickness of the nickel-based coating obtained in Comparative Example 4 was 550 μm.

[0095] Comparative Example 5

[0096] A method for preparing a nickel-based coating includes the following steps:

[0097] A preliminary nickel-based coating is obtained by flame spraying on the surface of a substrate using a nickel-based alloy as the raw material.

[0098] The initial nickel-based coating is remelted by laser heating to obtain a nickel-based coating.

[0099] The nickel-based alloy is Ni-20Cr-10TiC, and the nickel-based alloy is in the form of wire with an average diameter of 0.8 mm. The conveying speed of the nickel-based alloy is 2 m / min. The flame spraying temperature is 700℃, the flame spraying distance is 120 mm, and the moving speed of the flame spraying gun is 250 mm / s. The laser heating power is 800 W, the angle between the laser beam and the surface of the preliminary nickel-based coating is 50°, and the scanning speed of the laser beam is 250 mm / s.

[0100] The thickness of the nickel-based coating obtained in Comparative Example 5 was 350 μm.

[0101] Comparative Example 6

[0102] A method for preparing a nickel-based coating includes the following steps:

[0103] A preliminary nickel-based coating is obtained by flame spraying on the surface of a substrate using a nickel-based alloy as the raw material.

[0104] The initial nickel-based coating is remelted by laser heating to obtain a nickel-based coating.

[0105] The nickel-based alloy is Ni-20Cr-10TiC, and the nickel-based alloy is in the form of wire with an average diameter of 1.2 mm. The conveying speed of the nickel-based alloy is 5 m / min. The flame spraying temperature is 1300℃, the flame spraying distance is 120 mm, and the moving speed of the flame spraying gun is 150 mm / s. The laser heating power is 1500 W, the angle between the laser beam and the surface of the preliminary nickel-based coating is 65°, and the scanning speed of the laser beam is 250 mm / s.

[0106] The thickness of the nickel-based coating obtained in Comparative Example 6 was 450 μm.

[0107] Performance testing

[0108] The hardness and porosity of the nickel-based coatings prepared in the examples and comparative examples were tested, and the test results are shown in Table 1.

[0109] Table 1. Results of Hardness and Porosity Tests

[0110]

[0111] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several improvements and additions without departing from the method of the present invention, and these improvements and additions should also be considered within the scope of protection of the present invention.

Claims

1. A method for the production of a nickel-based coating, characterized in that The method comprises the following steps: flame spraying a nickel-based alloy on the surface of a substrate to obtain a preliminary nickel-based coating; remelting the preliminary nickel-based coating by laser heating to obtain a nickel-based coating; the nickel-based alloy is Ni-20Cr-10TiC, the nickel-based alloy is in the form of a wire, and the average diameter of the wire is 1.0 mm-1.6 mm; the conveying speed of the nickel-based alloy is 3 m / min-6 m / min; the temperature of the flame spraying is 800℃-1200℃, the distance of the flame spraying is 150 mm-250 mm, and the moving speed of the spray gun of the flame spraying is 100 mm / s-200 mm / s; the scanning speed of the laser beam of the laser heating is 100 mm / s-200 mm / s, the power of the laser heating is 1000 W-2000 W, and the included angle between the laser beam of the laser heating and the surface of the preliminary nickel-based coating is 45°-60°.

2. Application of the preparation method of the nickel-based coating according to claim 1 in the manufacture of high-temperature wear parts.

3. A nickel-based coating characterized in that, the nickel-based coating is prepared according to the preparation method of claim 1, and the thickness of the nickel-based coating is 100 μm-500 μm.

4. Application of the nickel-based coating according to claim 3 as a surface protective layer of a high-temperature wear part.

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