A kind of anti-falling and high temperature corrosion resistant coating and material, preparation method and application

Abstract

The present invention discloses an anti-shedding and high-temperature corrosion resistant coating and material, preparation method and application, belonging to the technical field of pipeline anti-corrosion. The anti-shedding and high-temperature corrosion resistant coating material disclosed by the present invention adopts V, Ta and Mo doped into Cr and Al to produce different degrees of lattice expansion, which helps to improve the phase structure stability of the coating, thereby enhancing the antioxidant performance; and each element works synergistically with Cr to improve the thermal stability of the overall structure, and significantly improves the antioxidant performance of the coating in a high-temperature steam environment; at the same time, the coating material can form a metallurgically bonded coating on the surface of the substrate, significantly improving the bonding force between the coating and the substrate, and when serving in a high-temperature steam environment, it can significantly improve the antioxidant performance, solving the problem of easy shedding of the existing coating.

Description

Technical Field

[0001] The present invention belongs to the technical field of pipeline anti-corrosion, and in particular relates to an anti-shedding and high-temperature corrosion resistant coating and material, a preparation method and application thereof. Background Art

[0002] Boiler flow components, especially those related to circulating fluidized bed boilers, have made significant technological progress in recent years; large-capacity circulating fluidized bed boiler technology has achieved circulating combustion of coal, effectively extended the combustion time, and improved the utilization efficiency of coal; at the same time, the boiler flow components, especially the material usage of circulating fluidized bed boilers, can be adjusted, so that the boiler can maintain stable performance during operation, and can even operate normally under low load conditions. The circulating fluidized bed boiler separates high-temperature solid materials from the air flow through the main circulation loop and returns them to the combustion chamber, realizing multiple circulations and repeated combustion of fuel and desulfurizer, thereby improving the combustion efficiency and desulfurization efficiency of the fuel. Circulating fluidized bed boiler technology not only improves the combustion efficiency of materials, but also provides a rich selection of fuel types to meet different production needs; but during use, how to ensure the working performance of boiler flow components has become a focus of attention.

[0003] Boiler flow components are usually used in high-temperature environments, such as 650°C. When the high-temperature steam on the inner wall contacts the metal wall, an oxidation reaction will occur to form an oxide film. As corrosion continues, the oxide film gradually thickens, resulting in a reduction in the effective thickness of the metal wall, which seriously affects the service life of the components. At the same time, when the oxide film reaches a certain thickness, due to the difference in physical properties between the oxide film and the base metal (such as the difference in linear expansion coefficient), the oxide film may peel off during the start-up and shutdown of the boiler. The peeled oxide may accumulate in the pipeline, such as at the bottom of the U-elbow of the vertical tube screen, causing pipeline blockage or over-temperature burst, posing a safety hazard.

[0004] In this regard, how to improve the high-temperature corrosion performance of the inner wall of the boiler flow-through components by coating becomes the key. The existing coating usually uses a slurry with certain anti-corrosion function to brush on the inner wall surface to form an anti-corrosion coating. However, when the coating is corroded by high-temperature steam, the following problems are prone to occur: Due to the corrosive effect of high-temperature steam, the adhesion between the coating and the substrate may be reduced, resulting in peeling of the coating. Especially during the start-up and shutdown of the boiler, load fluctuations, etc., the rapid change in temperature may cause the coating to peel off more. The degradation of the coating performance will make it unable to effectively resist the erosion of high-temperature steam, resulting in coating failure, and then affecting the performance of the flow-through components themselves. During the high-temperature steam corrosion process, an oxide film may form on the surface of the coating. However, when the oxide film reaches a certain thickness or encounters temperature fluctuations, it may peel off. The peeled oxide film may block the pipeline and affect the normal operation of the boiler; the peeled coating material and oxide film may enter the condensate system and become deposits in the scaling parts of the thermal equipment. These deposits will reduce the thermal efficiency of the equipment, increase energy consumption, and may cause other safety problems. Summary of the invention

[0005] The purpose of the present invention is to provide an anti-shedding and high-temperature corrosion-resistant coating and material, a preparation method and application, so as to solve the technical problem that the existing anti-corrosion coating is prone to oxidation and shedding in a high-temperature steam environment.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] The present invention discloses an anti-shedding and high-temperature corrosion resistant coating material. The raw materials of the anti-shedding and high-temperature corrosion resistant coating material include, by mass percentage:

[0008] 45%-70% Cr, 3%-15% Fe, 2%-8% Al, 1%-10% V, 4%-8% Ta, 2%-8% Mo, 5.5%-6% La and 3%-6% Ce.

[0009] The present invention also discloses a method for preparing an anti-shedding and high-temperature corrosion resistant coating, comprising the following steps:

[0010] In terms of mass percentage, 45%-70% of Cr, 3%-15% of Fe, 2%-8% of Al, 1%-10% of V, 4%-8% of Ta, 2%-8% of Mo, 5.5%-6% of La and 3%-6% of Ce are mixed to obtain an anti-shedding and high-temperature corrosion resistant coating material;

[0011] After the substrate is pretreated, the substrate is embedded with an anti-shedding and anti-high-temperature corrosion coating material, and then heat-treated. After the heat treatment is completed, an anti-shedding and anti-high-temperature corrosion coating is formed.

[0012] Furthermore, the mixing method is one ball milling, and the time of the one ball milling is 12-24 hours.

[0013] Furthermore, the mixing further includes secondary ball milling and drying to obtain an anti-shedding and high-temperature corrosion-resistant coating material;

[0014] The secondary ball milling time is 6-24 hours; the drying temperature is 80-120° C., and the drying time is 12-24 hours.

[0015] Further, the pretreatment of the substrate includes surface cleaning and preheating in sequence;

[0016] The preheating temperature is 220-250° C. and the preheating time is 30-60 minutes.

[0017] Furthermore, the heat treatment is a high-temperature sintering treatment, and the high-temperature sintering treatment is carried out in an inert atmosphere; the temperature of the high-temperature sintering treatment is 850-1150° C., and the time of the high-temperature sintering treatment is 8-15 minutes.

[0018] The invention also discloses an anti-shedding and high-temperature corrosion resistant coating prepared by the preparation method.

[0019] Furthermore, the anti-shedding and high-temperature corrosion resistant coating is metallurgically bonded to the substrate.

[0020] The invention also discloses the application of the anti-shedding and high-temperature corrosion resistant coating in the corrosion protection of the inner wall of the boiler flow-through component.

[0021] Furthermore, the material of the boiler flow-through component is austenitic steel or martensitic steel.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The invention discloses an anti-shedding and high-temperature corrosion resistant coating material, which adopts V, Ta and Mo to be doped into Cr and Al to produce different degrees of lattice expansion, which is helpful to improve the phase structure stability of the coating, thereby enhancing the antioxidant performance; and each element works synergistically with Cr to improve the thermal stability of the overall structure, and significantly improves the antioxidant performance of the coating in a high-temperature steam environment; at the same time, the coating material can form a metallurgically bonded coating on the surface of a substrate, significantly improving the bonding force between the coating and the substrate, and when serving in a high-temperature steam environment, it can significantly improve the antioxidant performance, and solves the problem that the existing coating is easy to fall off.

[0024] The present invention also discloses a method for preparing an anti-shedding and high-temperature corrosion-resistant coating using the above-mentioned material. A simple embedding and heating method can be used to form a metallurgically bonded coating on the surface of a substrate. The coating is well bonded to the substrate and does not change the performance of the substrate itself, and has broad application prospects.

[0025] Furthermore, this method can be applied to the preparation of inner wall coatings of special-shaped parts. Compared with traditional coating methods, this method is applicable to more scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic cross-sectional view of the anti-shedding and high-temperature corrosion resistant coating prepared by the present invention;

[0027] Figure 2 A comparison diagram of the high temperature corrosion resistance of the anti-shedding and high temperature corrosion resistant coating prepared by the present invention;

[0028] Where: a-coated sample; b-uncoated sample;

[0029] Figure 3 The data curve of the corrosion layer thickness of the anti-shedding and high-temperature corrosion resistant coating prepared by the present invention;

[0030] Figure 4 This is a cross-sectional view of the corrosion of the anti-shedding and high-temperature corrosion resistant coating prepared by the present invention in a steam environment;

[0031] Figure 5 This is a cross-sectional view of the corrosion of the coating prepared in the comparative example in a steam environment. DETAILED DESCRIPTION

[0032] In order to enable those skilled in the art to understand the characteristics and effects of the present invention, the following is a general description and definition of the terms and expressions mentioned in the specification and claims. Unless otherwise specified, all technical and scientific terms used in the text are the common meanings understood by those skilled in the art for the present invention. In the event of a conflict, the definition in this specification shall prevail.

[0033] The theories or mechanisms described and disclosed herein, whether correct or incorrect, should not limit the scope of the present invention in any way, that is, the present invention can be implemented without being limited by any specific theory or mechanism.

[0034] In this article, all features such as values, quantities, contents and concentrations defined in the form of numerical ranges or percentage ranges are for simplicity and convenience only. Accordingly, the description of numerical ranges or percentage ranges should be considered to have included and specifically disclosed all possible secondary ranges and individual values ​​within the range (including integers and fractions).

[0035] In this document, unless otherwise specified, “includes,” “including,” “contains,” “has,” or similar terms cover the meanings of “consisting of” and “mainly consisting of,” for example, “A includes a” covers the meanings of “A includes a and other” and “A only includes a.”

[0036] In this document, in order to make the description concise, not all possible combinations of various technical features in various embodiments or examples are described. Therefore, as long as there is no contradiction in the combination of these technical features, the various technical features in various embodiments or examples can be combined arbitrarily, and all possible combinations should be considered to be within the scope of this specification.

[0037] A first aspect of the present invention provides an anti-stripping and high-temperature corrosion resistant coating material, wherein the raw materials thereof include, by mass percentage, 45%-70% Cr, 3%-15% Fe, 2%-8% Al, 1%-10% V, 4%-8% Ta, 2%-8% Mo, 5.5-6% La and 3-6% Ce;

[0038] Among the above raw materials, V, Ta, and Mo are doped into Cr and Al to produce different degrees of lattice expansion, which helps to improve the phase structure stability of the coating, thereby enhancing the antioxidant performance; at the same time, each element works synergistically with Cr to improve the thermal stability of the overall structure; the above effects significantly improve the bonding strength between the coating and the substrate, and when serving in a high-temperature steam environment, it can significantly improve the antioxidant performance and solve the problem of easy shedding of existing coatings.

[0039] The second aspect of the present invention provides a method for preparing an anti-shedding and anti-high temperature corrosion coating using the above-mentioned anti-shedding and anti-high temperature corrosion coating material, which mainly comprises the following steps:

[0040] Weighing and mixing the raw materials to obtain an anti-shedding and high-temperature corrosion resistant coating material;

[0041] After the substrate is pretreated, the substrate is embedded with an anti-shedding and anti-high-temperature corrosion coating material, and then heat-treated. After the heat treatment, an anti-shedding and anti-high-temperature corrosion coating metallurgically bonded to the substrate is formed.

[0042] Preferably, the mixing method is one ball milling, and the time of the one ball milling is 12-24 hours.

[0043] Preferably, the mixing further includes secondary ball milling and drying to obtain an anti-shedding and high-temperature corrosion resistant coating material;

[0044] The secondary ball milling time is 6-24 hours; the drying temperature is 80-120° C., and the drying time is 12-24 hours.

[0045] Preferably, the pretreatment of the substrate includes surface cleaning and preheating in sequence;

[0046] The preheating temperature is 220-250° C. and the preheating time is 30-60 minutes.

[0047] Preferably, the heat treatment is a high-temperature sintering treatment, and the high-temperature sintering treatment is performed in an inert atmosphere; the temperature of the high-temperature sintering treatment is 850-1150° C.; and the time of the high-temperature sintering treatment is 8-15 minutes.

[0048] By adopting the above-mentioned preparation method, an anti-shedding and high-temperature corrosion-resistant coating metallurgically bonded to the substrate can be obtained, and this method can realize the preparation of anti-corrosion coatings for special-shaped parts that cannot be achieved by traditional coating methods.

[0049] The present invention will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall within the scope limited by the appended claims of the application equally.

[0050] The following examples use conventional instruments and equipment in the art. The experimental methods in the following examples where specific conditions are not specified are usually carried out under conventional conditions or under conditions recommended by the manufacturer. The various raw materials used in the following examples are conventional commercial products unless otherwise specified, and their specifications are conventional specifications in the art. In the specification of the present invention and the following examples, unless otherwise specified, "%" means weight percentage, "part" means weight part, and ratio means weight ratio.

[0051] Example 1

[0052] A method for preparing an anti-shedding and high-temperature corrosion-resistant coating comprises the following steps:

[0053] Step 1: According to mass percentage, 45% Cr, 15% Fe, 5% Al, 10% V, 5% Ta, 8% Mo, 6% La and 6% Ce are weighed, ball milled for 12 hours, and then ball milled for 24 hours, and then dried at 80°C for 24 hours to obtain an anti-shedding and high-temperature corrosion resistant coating material;

[0054] Step 2: Rinse the TP347HFG substrate with a high-pressure water gun, then rinse it with alcohol, preheat it at 220°C for 30 minutes, and set it aside;

[0055] Step 3: The TP347HFG substrate is embedded with an anti-shedding and anti-high-temperature corrosion coating material, and is subjected to a high-temperature sintering treatment at 980° C. for 10 minutes under an inert atmosphere. After the high-temperature sintering treatment, an anti-shedding and anti-high-temperature corrosion coating metallurgically bonded to the surface of the TP347HFG substrate is formed.

[0056] Example 2

[0057] A method for preparing an anti-shedding and high-temperature corrosion-resistant coating comprises the following steps:

[0058] Step 1: According to mass percentage, 69.5% Cr, 3% Fe, 8% Al, 1% V, 8% Ta, 2% Mo, 5.5% La and 3% Ce are weighed, ball milled for 20 hours, and then ball milled for 12 hours, and then dried at 100°C for 20 hours to obtain an anti-shedding and high-temperature corrosion resistant coating material;

[0059] Step 2: Rinse the HR3C substrate with a high-pressure water gun, then rinse it with alcohol, preheat it at 220°C for 60 minutes, and set it aside;

[0060] Step 3: The HR3C substrate is embedded with an anti-shedding and anti-high-temperature corrosion coating material, and is subjected to high-temperature sintering treatment at 850°C for 15 minutes under an inert atmosphere. After the high-temperature sintering treatment, an anti-shedding and anti-high-temperature corrosion coating metallurgically bonded to the HR3C substrate is formed on the surface of the HR3C substrate.

[0061] Example 3

[0062] A method for preparing an anti-shedding and high-temperature corrosion-resistant coating comprises the following steps:

[0063] Step 1: According to mass percentage, 50% Cr, 15% Fe, 2% Al, 10% V, 8% Ta, 6.5% Mo, 5.5% La and 3% Ce are weighed, ball milled for 24 hours, and then ball milled for 6 hours, and then dried at 120°C for 12 hours to obtain an anti-shedding and high-temperature corrosion resistant coating material;

[0064] Step 2: Rinse the TP347H substrate with a high-pressure water gun, then rinse it with alcohol, preheat it at 250°C for 40 minutes, and set it aside;

[0065] Step 3: The TP347H substrate is embedded with an anti-shedding and anti-high-temperature corrosion coating material, and is subjected to a high-temperature sintering treatment at 1000° C. for 10 minutes in an inert atmosphere. After the high-temperature sintering treatment, an anti-shedding and anti-high-temperature corrosion coating metallurgically bonded to the surface of the TP347H substrate is formed.

[0066] Example 4

[0067] A method for preparing an anti-shedding and high-temperature corrosion-resistant coating comprises the following steps:

[0068] Step 1: According to mass percentage, 70% Cr, 3% Fe, 2.5% Al, 10% V, 4% Ta, 2% Mo, 5.5% La and 3% Ce are weighed, ball milled for 24 hours, and then ball milled for 6 hours, and then dried at 120°C for 12 hours to obtain an anti-shedding and high-temperature corrosion resistant coating material;

[0069] Step 2: Rinse the Super304H substrate with a high-pressure water gun, then rinse it with alcohol, preheat it at 230°C for 40 minutes, and set it aside;

[0070] Step 3: The Super304H substrate is embedded with an anti-shedding and anti-high-temperature corrosion coating material, and is subjected to high-temperature sintering treatment at 1150°C for 15 minutes under an inert atmosphere. After the high-temperature sintering treatment, an anti-shedding and anti-high-temperature corrosion coating metallurgically bonded to the Super304H substrate is formed on the surface of the substrate.

[0071] Example 5

[0072] A method for preparing an anti-shedding and high-temperature corrosion-resistant coating comprises the following steps:

[0073] Step 1: According to mass percentage, 70% Cr, 3% Fe, 2.5% Al, 10% V, 4% Ta, 2% Mo, 5.5% La and 3% Ce are weighed, ball milled for 24 hours, and then ball milled for 6 hours, and then dried at 120°C for 12 hours to obtain an anti-shedding and high-temperature corrosion resistant coating material;

[0074] Step 2: Rinse the Super304H substrate with a high-pressure water gun, then rinse it with alcohol, preheat it at 230°C for 40 minutes, and set it aside;

[0075] Step 3: The Super304H substrate is embedded with an anti-shedding and anti-high-temperature corrosion coating material, and is subjected to high-temperature sintering treatment at 900°C for 10 minutes under an inert atmosphere. After the high-temperature sintering treatment, an anti-shedding and anti-high-temperature corrosion coating metallurgically bonded to the Super304H substrate is formed on the surface of the substrate.

[0076] Example 6

[0077] A method for preparing an anti-shedding and high-temperature corrosion-resistant coating comprises the following steps:

[0078] Step 1: According to mass percentage, 60% Cr, 13% Fe, 2.5% Al, 10% V, 4% Ta, 2% Mo, 5.5% La and 3% Ce are weighed, ball milled for 24 hours, and then ball milled for 6 hours, and then dried at 120°C for 12 hours to obtain an anti-shedding and high-temperature corrosion resistant coating material;

[0079] Step 2: Rinse the Super304H substrate with a high-pressure water gun, then rinse it with alcohol, preheat it at 230°C for 40 minutes, and set it aside;

[0080] Step 3: The Super304H substrate is embedded with an anti-shedding and anti-high-temperature corrosion coating material, and is subjected to high-temperature sintering treatment at 900°C for 10 minutes under an inert atmosphere. After the high-temperature sintering treatment, an anti-shedding and anti-high-temperature corrosion coating metallurgically bonded to the Super304H substrate is formed on the surface of the substrate.

[0081] Example 7

[0082] A method for preparing an anti-shedding and high-temperature corrosion-resistant coating comprises the following steps:

[0083] Step 1: According to mass percentage, 63% Cr, 10% Fe, 2.5% Al, 6% V, 8% Ta, 2% Mo, 5.5% La and 3% Ce were weighed, ball milled for 24 hours, and then ball milled for 6 hours, and then dried at 120°C for 12 hours to obtain an anti-shedding and high-temperature corrosion resistant coating material;

[0084] Step 2: Rinse the TP347H substrate with a high-pressure water gun, then rinse it with alcohol, preheat it at 250°C for 40 minutes, and set it aside;

[0085] Step 3: The TP347H substrate is embedded with an anti-shedding and anti-high-temperature corrosion coating material, and is subjected to high-temperature sintering treatment at 1000° C. for 8 minutes under an inert atmosphere. After the high-temperature sintering treatment, an anti-shedding and anti-high-temperature corrosion coating metallurgically bonded to the surface of the TP347H substrate is formed.

[0086] Example 8

[0087] A method for preparing an anti-shedding and high-temperature corrosion-resistant coating comprises the following steps:

[0088] Step 1: According to mass percentage, 63% Cr, 10% Fe, 2.5% Al, 6% V, 8% Ta, 2% Mo, 5.5% La and 3% Ce were weighed, ball milled for 24 hours, and then ball milled for 6 hours, and then dried at 110°C for 24 hours to obtain an anti-shedding and high-temperature corrosion resistant coating material;

[0089] Step 2: Rinse the TP347H substrate with a high-pressure water gun, then rinse it with alcohol, preheat it at 250°C for 40 minutes, and set it aside;

[0090] Step 3: The TP347H substrate is embedded with an anti-shedding and anti-high-temperature corrosion coating material, and is subjected to a high-temperature sintering treatment at 1000° C. for 10 minutes in an inert atmosphere. After the high-temperature sintering treatment, an anti-shedding and anti-high-temperature corrosion coating metallurgically bonded to the surface of the TP347H substrate is formed.

[0091] Example 9

[0092] A method for preparing an anti-shedding and high-temperature corrosion-resistant coating comprises the following steps:

[0093] Step 1: According to mass percentage, 63% Cr, 10% Fe, 2.5% Al, 6% V, 8% Ta, 2% Mo, 5.5% La and 3% Ce were weighed, ball milled for 24 hours, and then ball milled for 6 hours, and then dried at 120°C for 12 hours to obtain an anti-shedding and high-temperature corrosion resistant coating material;

[0094] Step 2: Rinse the TP347H substrate with a high-pressure water gun, then rinse it with alcohol, preheat it at 240°C for 50 minutes, and set aside;

[0095] Step 3: The TP347H substrate is embedded with an anti-shedding and anti-high-temperature corrosion coating material, and is subjected to a high-temperature sintering treatment at 1000° C. for 10 minutes in an inert atmosphere. After the high-temperature sintering treatment, an anti-shedding and anti-high-temperature corrosion coating metallurgically bonded to the surface of the TP347H substrate is formed.

[0096] Example 10

[0097] A method for preparing an anti-shedding and high-temperature corrosion-resistant coating comprises the following steps:

[0098] Step 1: According to mass percentage, 60% Cr, 13% Fe, 2.5% Al, 10% V, 4% Ta, 2% Mo, 5.5% La and 3% Ce were weighed, ball milled for 12 hours, and then ball milled for 10 hours, and then dried at 120°C for 12 hours to obtain an anti-shedding and high-temperature corrosion resistant coating material;

[0099] Step 2: Rinse the Super304H substrate with a high-pressure water gun, then rinse it with alcohol, preheat it at 230°C for 40 minutes, and set aside;

[0100] Step 3: The Super304H substrate is embedded with an anti-shedding and anti-high-temperature corrosion coating material, and is subjected to high-temperature sintering treatment at 860°C for 8 minutes under an inert atmosphere. After the high-temperature sintering treatment, an anti-shedding and anti-high-temperature corrosion coating metallurgically bonded to the Super304H substrate is formed on the surface of the substrate.

[0101] Embodiment 11

[0102] A method for preparing an anti-shedding and high-temperature corrosion-resistant coating comprises the following steps:

[0103] Step 1: According to mass percentage, 50% Cr, 15% Fe, 2% Al, 10% V, 8% Ta, 6.5% Mo, 5.5% La and 3% Ce are weighed, ball milled for 24 hours, and then ball milled for 6 hours, and then dried at 120°C for 12 hours to obtain an anti-shedding and high-temperature corrosion resistant coating material;

[0104] Step 2: Rinse the TP347H substrate with a high-pressure water gun, then rinse it with alcohol, preheat it at 250°C for 60 minutes, and set it aside;

[0105] Step 3: The TP347H substrate is embedded with an anti-shedding and anti-high-temperature corrosion coating material, and is subjected to high-temperature sintering treatment at 1130° C. for 12 minutes under an inert atmosphere. After the high-temperature sintering treatment, an anti-shedding and anti-high-temperature corrosion coating metallurgically bonded to the surface of the TP347H substrate is formed.

[0106] Comparative Example

[0107] Different from Example 1, the components of the coating raw material in the comparative example are composed of 60% high carbon ferrochrome, 38% Al2O3 and 2% NH4Cl in terms of mass percentage, the temperature and time of the high temperature sintering treatment are 950°C and 4h respectively, and the remaining steps are the same as in Example 1, and a coating with a thickness of 39.12μm is prepared.

[0108] Figure 1 Shown is a cross-sectional view of the anti-shedding and high-temperature corrosion resistant coating prepared in Example 1 of the present invention. It can be seen that a metallurgical bond is formed between the anti-shedding and high-temperature corrosion resistant coating and the base material, and the coating has a double-layer structure.

[0109] Figure 2 The figure shows a cross-sectional comparison of the corrosion layer of the anti-shedding high-temperature corrosion resistant coating and the uncoated base material sample prepared in Example 2 of the present invention. Figure 3 The data comparison curve of the corrosion layer thickness of the anti-shedding high-temperature corrosion resistant coating and the uncoated base material sample prepared in Example 2 of the present invention. It can be seen that after corrosion for 1000 hours in a 650°C high-temperature pure water vapor environment, the corrosion layer thickness of the coating sample surface is about 3.19 μm, and the corrosion layer thickness of the uncoated sample surface is about 43.24 μm. After calculation, the average corrosion rates of the coating sample and the uncoated sample are 3.4×10 -5 mg / (cm 2 h) and 2.3×10 -3 mg / (cm 2 ·h), from the order of magnitude, the high temperature corrosion resistance of the coated samples is improved by about two orders of magnitude compared with that of the uncoated samples, and the resistance to high temperature steam oxidation is significantly improved.

[0110] Figure 4The figure shows the cross-sectional view of the anti-shedding and high-temperature corrosion-resistant coating prepared in Example 4 after being corroded in a 650°C steam environment for 1000 h. It can be seen that the structure of the coating after corrosion is still intact, and there is no shedding or peeling of the coating. Only microcracks with a nanometer width appear on the surface, and the microcracks are filled with dense oxides to prevent further expansion of the cracks. The thickness of the corrosion layer on the coating surface is about 1.36 μm. After calculation, the average corrosion rate is 1.3×10 -5 mg / (cm 2 h), excellent corrosion resistance.

[0111] Figure 5 The figure shows a cross-sectional view of the coating prepared in the comparative example after corrosion for 1000 hours in a 650°C steam environment. It can be seen that after corrosion, the coating has large-scale shedding and multiple obvious cracks. The coating is brittle and easy to crack, and has poor metallurgical bonding strength.

[0112] Table 1 below shows the performance test data of the coatings prepared in various test examples of the present invention in a 650° C. steam environment for 1000 hours of corrosion.

[0113] Table 1 Performance experimental data of the coatings prepared in each test example in a 650℃ steam environment for 1000h corrosion

[0114]

[0115] Combination Figure 1-Figure 5 A comparative analysis with the data in Table 1 shows that the coating material of the present invention can form a metallurgically bonded coating on the surface of the substrate, significantly improving the bonding strength between the coating and the substrate. When serving in a high-temperature steam environment, it can significantly improve the anti-oxidation performance, while effectively solving the problem of easy shedding of the existing coating.

[0116] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A method for preparing an anti-shedding and high-temperature corrosion-resistant coating, characterized in that: The following steps are involved: In terms of mass percentage, 45%-70% of Cr, 3%-15% of Fe, 2%-8% of Al, 1%-10% of V, 4%-8% of Ta, 2%-8% of Mo, 5.5%-6% of La and 3%-6% of Ce are mixed to obtain an anti-shedding and high-temperature corrosion resistant coating material; After the substrate is pretreated, the substrate is embedded with an anti-shedding and anti-high-temperature corrosion coating material, and then subjected to a high-temperature sintering treatment. After the high-temperature sintering treatment is completed, an anti-shedding and anti-high-temperature corrosion coating is formed.

2. The method for preparing an anti-shedding and high-temperature corrosion-resistant coating according to claim 1, characterized in that: The mixing method is one ball milling, and the time of the one ball milling is 12-24 hours.

3. The method for preparing an anti-shedding and high-temperature corrosion resistant coating according to claim 1, characterized in that: The mixing process further includes secondary ball milling and drying to obtain an anti-shedding and high-temperature corrosion resistant coating material; The secondary ball milling time is 6-24 hours; the drying temperature is 80-120° C., and the drying time is 12-24 hours.

4. The method for preparing an anti-shedding and high-temperature corrosion resistant coating according to claim 1, characterized in that: The pretreatment of the substrate includes surface cleaning and preheating in sequence; The preheating temperature is 220-250° C. and the preheating time is 30-60 minutes.

5. The method for preparing an anti-shedding and high-temperature corrosion resistant coating according to claim 1, characterized in that: The high temperature sintering treatment is carried out in an inert atmosphere; the temperature of the high temperature sintering treatment is 850-1150° C., and the time of the high temperature sintering treatment is 8-15 minutes.

6. An anti-shedding and high-temperature corrosion-resistant coating, characterized in that: The method is prepared by any one of claims 1 to 5.

7. The anti-shedding and high-temperature corrosion resistant coating according to claim 6, characterized in that: The anti-shedding and high-temperature corrosion-resistant coating is metallurgically bonded to the substrate.

8. Application of the anti-shedding and high-temperature corrosion-resistant coating as described in claim 6 in the corrosion protection of the inner wall of boiler flow-through components.

9. The use of an anti-shedding and high-temperature corrosion resistant coating according to claim 8 in the anti-corrosion of the inner wall of a boiler flow-through component, characterized in that: The material of the boiler flow-through component is austenitic steel or martensitic steel.

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