Coating material system with synergistic effect of barrier layer and anti-oxidation layer on metal surface and preparation method

Abstract

The invention provides a coating material system with a synergistic effect of a barrier layer and an anti-oxidation layer on a metal surface. The coating material system is composed of a first protective layer and a second protective layer, wherein the first protective layer is formed by Y2O3 and / or CeO2, and the second protective layer is formed by Ni-55Al-12Si-Y-Hf-Zr. According to the invention, the synergistic effect between the first protective layer formed by Y2O3 and / or CeO2 and the second protective layer formed by Ni-55Al-12Si-Y-Hf-Zr is fully exerted, so that the coating material system can realize the long-term oxidation resistance of the hot end part of the gas turbine at 1000-1100 DEG C. The invention further provides a preparation method of the coating material system with the synergistic effect of the barrier layer and the anti-oxidation layer on the metal surface, according to the method, the first protection layer composed of Y2O3 and / or CeO2 is prepared in a supersaturated solution dipping mode, and the second protection layer composed of Ni-55Al-12Si-Y-Hf-Zr is further prepared on the basis of the first protection layer through a slurry method. And the prepared coating material system is uniform and compact, and the uniformity of preparation of the coating material system can be ensured even for hot end components with complex inner cavities and appearance structures with small angles and the like.

Description

Technical Field

[0001] The invention relates to the technical field of composite coatings, and in particular to a coating material system and a preparation method of a synergistic barrier layer and an anti-oxidation layer on a metal surface. Background Art

[0002] The existing protective (anti-oxidation) coating materials on the surface of high-temperature alloy (titanium-based, iron-based, nickel-based) substrates are generally aluminum-containing aluminide coatings, such as aluminide coatings NiAl, NiCoCrAlY, and AlNiCr-based high entropy alloys, which have been widely used in long-term anti-oxidation technology. Its anti-oxidation mechanism is to form a dense Al2O3 film on the surface to protect the metal substrate.

[0003] However, during long-term high-temperature service, Al elements will be continuously consumed. There is also mutual diffusion between the anti-oxidation coating and the substrate interface, that is, Al elements will diffuse outward to form Al2O3, and will also diffuse inward to form harmful intermetallic compounds with the high-temperature alloy interface, which will have an adverse effect on the high-temperature durability of the substrate material, resulting in the alloy material not meeting the requirements of long-term stable anti-oxidation for more than 5,000 hours.

[0004] In addition, for hot end components with complex internal cavities and external structures such as small angles, thermal spraying, CVD, PVD and other technologies cannot achieve uniform preparation of coatings. Summary of the invention

[0005] In view of the above problems existing in the prior art, the present invention provides a coating material system with a metal surface barrier layer and an anti-oxidation layer acting in synergy, and adopts a coating structure of a surface diffusion barrier layer + an anti-oxidation layer to meet the demand for long-term anti-oxidation of the metal substrate for thousands of hours. The present invention also provides a method for preparing a coating material system with a metal surface barrier layer and an anti-oxidation layer acting in synergy to achieve uniform preparation of the above coating on the surface of the substrate.

[0006] The specific content of the invention is as follows:

[0007] In a first aspect, the present invention provides a method for preparing a coating material system having a synergistic effect of a barrier layer and an anti-oxidation layer on a metal surface, the method comprising the following steps:

[0008] S1, immersing the alloy substrate in a supersaturated solution of Y2O3 and / or CeO2, so that the surface of the alloy substrate is coated with a 2-3 μm thick crystal layer, and then transferring the alloy substrate to an oven for drying to obtain an alloy substrate with a first protective layer formed on the surface;

[0009] S2. Under argon protection, heat-treating the alloy substrate with the first protective layer formed on the surface at 300-500° C. for 2-5 hours;

[0010] S3, after uniformly mixing the Ni-55Al-12Si-Y-Hf-Zr powder material, adding it into a mixed solution consisting of water, phosphoric acid, chromium oxide and magnesium oxide to prepare a slurry, and then uniformly spraying the slurry on the surface of the alloy substrate treated by S2;

[0011] Step 4: Under argon protection, the alloy substrate treated with S3 is subjected to a heat treatment at 1000-1100° C. for 2-5 hours to obtain the coating material system.

[0012] Optionally, in step S1, the drying temperature is 200° C., and the drying time is 30 minutes.

[0013] Optionally, in step S2, the heat treatment temperature is 500°C and the heat treatment time is 2 hours.

[0014] Optionally, in step S3, the Ni-55Al-12Si-Y-Hf-Zr powder material is a mixture of Ni, Al-12Si, Y2O3, HfO and ZrO2 in a mass ratio of 5:4:3:1:1.

[0015] Optionally, in step S3, in the slurry, the mass volume ratio of the Ni-55Al-12Si-Y-Hf-Zr powder material to the mixed solution is 1 g:1 ml;

[0016] In the mixed solution, the mass ratio of water, phosphoric acid, chromium oxide and magnesium oxide is 50:16.7:16.7:16.7.

[0017] Optionally, in step S3, the particle size of the Ni-55Al-12Si-Y-Hf-Zr powder material is in micron order.

[0018] Optionally, in step S4, the heat treatment temperature is 1050° C. and the heat treatment time is 2 h.

[0019] In a second aspect, the present invention provides a coating material system having a synergistic effect of a metal surface barrier layer and an anti-oxidation layer obtained by the preparation method described in the first aspect, wherein the coating material system is composed of a first protective layer composed of Y2O3 and / or CeO2, and a second protective layer composed of Ni-55Al-12Si-Y-Hf-Zr.

[0020] Optionally, the total thickness of the coating material system is 30-40 μm, wherein the thickness of the first protective layer is 2-3 μm.

[0021] Optionally, the high-temperature alloy substrate includes: heat-resistant stainless steel 310S, high-temperature alloy K456, Incoloy M956 or DZ640M.

[0022] Optionally, the surface of the high-temperature alloy substrate is a surface of the high-temperature alloy substrate that has been degreased and sandblasted;

[0023] The coating material system is used to protect the high-temperature alloy substrate to work stably at 1000-1100°C.

[0024] Compared with the prior art, the present invention has the following advantages:

[0025] The present invention provides a coating material system with a metal surface barrier layer and an anti-oxidation layer acting in synergy, wherein the coating material system is composed of a first protective layer formed by Y2O3 and / or CeO2 and a second protective layer formed by Ni-55Al-12Si-Y-Hf-Zr. The present invention gives full play to the synergy between the first protective layer formed by Y2O3 and / or CeO2 and the second protective layer formed by Ni-55Al-12Si-Y-Hf-Zr, so that the coating material system can achieve long-term anti-oxidation performance of the hot end components of a gas turbine at 1000-1100°C.

[0026] The present invention also provides a method for preparing a coating material system with synergistic effects of a metal surface barrier layer and an antioxidant layer. The method adopts a supersaturated solution impregnation method to prepare a first protective layer composed of Y2O3 and / or CeO2, and further adopts a slurry method to prepare a second protective layer composed of Ni-55Al-12Si-Y-Hf-Zr on the basis of the first protective layer. The prepared coating material system is uniform and dense, and the uniformity of the coating material system preparation can be guaranteed even for hot end components with complex inner cavities and external structures such as small angles. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 A flow chart of a method for preparing a coating material system provided by an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means a limitation on the present invention and its application or use. Based on the embodiments of the present invention, any product identical or similar to the present invention obtained by anyone under the inspiration of the present invention or by combining the features of the present invention with other prior arts falls within the scope of protection of the present invention. In addition, all other embodiments obtained by ordinary technicians in this field without carrying out creative work belong to the scope of protection of the present invention.

[0030] In the embodiment, no specific experimental steps or conditions are indicated, and the operation or conditions of the conventional experimental steps described in the prior art in this field can be carried out. The reagents used and other instruments that do not indicate the manufacturer are conventional reagent products that can be obtained commercially. In addition, the accompanying drawings are only schematic diagrams of the embodiments of the present invention and are not necessarily drawn to scale. The same reference numerals in the figures represent the same or similar parts, and thus their repeated description will be omitted. Some block diagrams shown in the accompanying drawings are functional entities and do not necessarily correspond to physically or logically independent entities.

[0031] Technologies, methods, and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the description of the present invention.

[0032] In the description of the present invention, it should be understood that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0033] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0034] In a first aspect, the present invention provides a method for preparing a coating material system having a synergistic effect of a metal surface barrier layer and an anti-oxidation layer. Figure 1 The flow chart of the method for preparing the coating material system provided by the embodiment of the present invention is shown as follows: Figure 1 As shown, the method comprises the following steps:

[0035] S1, immersing the alloy substrate in a supersaturated solution of Y2O3 and / or CeO2, so that the surface of the alloy substrate is coated with a 2-3 μm thick crystal layer, and then transferring the alloy substrate to an oven for drying to obtain an alloy substrate with a first protective layer formed on the surface;

[0036] S2. Under argon protection, heat-treating the alloy substrate with the first protective layer formed on the surface at 300-500° C. for 2-5 hours;

[0037] S3, after uniformly mixing the Ni-55Al-12Si-Y-Hf-Zr powder material, adding it into a mixed solution consisting of water, phosphoric acid, chromium oxide and magnesium oxide to prepare a slurry, and then uniformly spraying the slurry on the surface of the alloy substrate treated by S2;

[0038] Step 4: Under argon protection, the alloy substrate treated with S3 is subjected to a heat treatment at 1000-1100° C. for 2-5 hours to obtain the coating material system.

[0039] In specific implementation, the embodiment of the present invention adopts the method of impregnation with a supersaturated solution to prepare a first protective layer composed of Y2O3 and / or CeO2 on the surface of the high-temperature alloy. Due to the chemical stability and lattice structure characteristics of Y2O3 and CeO2, they play an important role in preventing the diffusion of atoms or ions. As a protective coating in direct contact with the surface of the high-temperature alloy, Y2O3 and / or CeO2 can effectively inhibit the diffusion of metal elements in the alloy matrix and have a high diffusion barrier ability. In addition, Y2O3 and CeO2 can form a dense reaction layer or oxide film with the alloy substrate, which can prevent further oxidation and corrosion of the metal surface and further slow down the mutual reaction rate of the metal elements. By hindering the mutual penetration between metal elements, the mutual diffusion in the alloy matrix can be effectively reduced. Therefore, the first protective layer composed of Y2O3 and / or CeO2 has a high melting point and thermal stability, can maintain good chemical stability and structural stability, and protect the alloy matrix from the influence of element diffusion and reaction in a high temperature environment.

[0040] In specific implementation, the supersaturated solution impregnation method can achieve uniform preparation of the first protective layer on the hot end components with complex inner cavities and external structures such as small angles, and the preparation method is simple.

[0041] In the specific implementation, the first protective layer prepared by the supersaturated solution impregnation method is subjected to a heat treatment at 300-500°C for 2-5 hours under argon protection, so that the first protective layer obtains sufficient shrinkage energy for further densification and improves the bonding strength with the substrate; to avoid the problem of pores and coating cracks when used at high temperature in the later stage, which affects the quality of the final coating system. The preferred heat treatment temperature is 500°C and the time is 2 hours.

[0042] In specific implementation, the Ni-55Al-12Si-Y-Hf-Zr powder material selected in this embodiment is specifically mixed with Ni, Al-12Si, Y2O3, HfO and ZrO2 in a mass ratio of 5:4:3:1:1, and the mixed Ni-55Al-12Si-Y-Hf-Zr powder material is mixed with a mixed solution to prepare a slurry. Among them, the mass volume ratio of the Ni-55Al-12Si-Y-Hf-Zr powder material to the mixed solution is 1g:1ml; the mixed solution is specifically mixed with water, phosphoric acid, chromium oxide and magnesium oxide in a mass ratio of 50:16.7:16.7:16.7.

[0043] In specific implementation, the particle size of the Ni-55Al-12Si-Y-Hf-Zr powder material selected in this embodiment is micrometer-level to ensure the uniformity of slurry spraying. After the slurry is sprayed on the surface of the first protective layer, a high-temperature heat treatment is performed to achieve a sufficient metallurgical bonding between the Ni-55Al-12Si-Y-Hf-Zr powder material and the first protective layer. The preferred heat treatment temperature is 1050°C and the time is 2 hours.

[0044] In a second aspect, the present invention provides a coating material system having a synergistic effect of a metal surface barrier layer and an anti-oxidation layer obtained by the method described in the first aspect, wherein the coating material system is composed of a first protective layer composed of Y2O3 and / or CeO2, and a second protective layer composed of Ni-55Al-12Si-Y-Hf-Zr. The total thickness of the coating material system is 30-40 μm, and the thickness of the first protective layer is 2-3 μm.

[0045] Furthermore, the second protective layer composed of Ni-55Al-12Si-Y-Hf-Zr further protects the first protective layer, reducing the damage to the first protective layer by the external environment. In addition, since the anti-oxidation and anti-corrosion capabilities of the Ni-55Al-12Si-Y-Hf-Zr material are outstanding in the protective layer, combined with the Y2O3 and / or CeO2 coating, it can further improve the heat corrosion resistance and wear resistance, further improve the overall thermal stability of the coating, enhance the anti-oxidation performance, heat corrosion resistance, improve the hardness and wear resistance, and prevent the coating from cracking and peeling when working at high temperatures. Such a combination can provide a stronger protective layer for high-temperature alloys and extend the service life.

[0046] The high temperature alloy substrate used in the coating material system provided by the present invention includes: heat-resistant stainless steel 310S, high temperature alloy K456, Incoloy M956 or DZ640M. Before preparing the coating material system, the surface of the high temperature alloy substrate needs to be degreased and sandblasted to keep the surface clean.

[0047] The coating material system provided by the embodiment of the present invention can be used to protect a high-temperature alloy substrate to work stably at 1000-1100°C.

[0048] In order to enable those skilled in the art to more clearly understand the present invention, the coating material system and preparation method of the synergistic metal surface barrier layer and anti-oxidation layer described in the present invention are now described in detail through the following examples.

[0049] Example 1

[0050] Nickel-based high-temperature alloy K465 alloy has high creep resistance, fatigue resistance and high temperature bearing capacity. This material is used as the high-temperature alloy matrix material and is fixed by a fixing clamping device.

[0051] After surface sandblasting and cleaning, the high-temperature alloy substrate material was placed in a supersaturated mixed solution of yttrium oxide and cerium oxide for 2 minutes; yttrium oxide and cerium oxide grains were evenly attached to the surface of the high-temperature alloy substrate, and then placed in an oven at 200° C. for 30 minutes for drying.

[0052] Under argon protective gas, the dried upper high temperature alloy substrate material is heat treated at 500°C for 2 hours to form a dense first protective layer composed of Y2O3 or CeO2 on its surface. At the same time, the heat treatment improves the bonding strength between the coating and the substrate.

[0053] Ni, Al-12Si, Y2O3, HfO and ZrO2 in a mass ratio of 5:4:3:1:1 were weighed and mixed to form a Ni-55Al-12Si-Y-Hf-Zr powder material, and added to a mixed solution formed by mixing water, phosphoric acid, chromium oxide and magnesium oxide in a mass ratio of 50:16.7:16.7:16.7 to prepare a slurry, which was evenly sprayed on the surface of the first protective layer. After drying, the slurry was heat treated at 1050°C for 2 hours to obtain a 30-40 micron coating system.

[0054] Example 2

[0055] M956 alloy has high endurance strength and excellent oxidation and corrosion resistance at high temperatures. It is widely used as the hot end parts of advanced aircraft engines with operating temperatures of 1000-1200°C and heat protection parts in industrial furnaces exceeding 1300°C. This material is used as the high-temperature alloy matrix material and fixed by a fixing clamping device.

[0056] After surface sandblasting and cleaning, the high-temperature alloy substrate material was placed in a supersaturated yttrium oxide mixed solution for 2 minutes to allow yttrium oxide grains to evenly adhere to the surface of the high-temperature alloy substrate, and then placed in an oven at 200° C. for 30 minutes for drying.

[0057] Under argon protective gas, the dried upper high temperature alloy substrate material is heat treated at 500°C for 2 hours to form a dense first protective layer composed of Y2O3 on its surface. At the same time, the heat treatment improves the bonding strength between the coating and the substrate.

[0058] Ni, Al-12Si, Y2O3, HfO and ZrO2 in a mass ratio of 5:4:3:1:1 were weighed and mixed to form a Ni-55Al-12Si-Y-Hf-Zr powder material, and added to a mixed solution formed by mixing water, phosphoric acid, chromium oxide and magnesium oxide in a mass ratio of 50:16.7:16.7:16.7 to prepare a slurry, which was evenly sprayed on the surface of the first protective layer. After drying, the slurry was heat treated at 1050°C for 2 hours to obtain a 30-40 micron coating system.

[0059] Example 3

[0060] Heat-resistant stainless steel 310S is austenitic stainless steel with good oxidation resistance and corrosion resistance. Due to the high percentage of chromium and nickel, it has good creep strength, can work continuously at high temperatures, and has good high temperature resistance. This material is used as the high-temperature alloy matrix material and fixed by a fixed clamping device.

[0061] After the surface is sandblasted and cleaned, the high-temperature alloy substrate material is placed in a supersaturated cerium oxide mixed solution for 2 minutes to allow cerium oxide grains to evenly adhere to the surface of the high-temperature alloy substrate, and then placed in an oven at 200° C. for 30 minutes for drying.

[0062] Under argon protective gas, the dried upper high temperature alloy substrate material is heat treated at 500°C for 2 hours to form a dense first protective layer composed of cerium oxide on its surface. At the same time, the heat treatment improves the bonding strength between the coating and the substrate.

[0063] Weigh Ni, Al-12Si, Y2O3, HfO and ZrO2 powders in a mass ratio of 5:4:3:1:1 and mix them to form a Ni-55Al-12Si-Y-Hf-Zr powder material, and add it to a mixed solution formed by mixing water, phosphoric acid, chromium oxide and magnesium oxide in a mass ratio of 50:16.7:16.7:16.7 to prepare a slurry, which is evenly sprayed on the surface of the first protective layer. After drying, heat treatment is performed at 1050°C for 2 hours to obtain a 30-40 micron coating system.

[0064] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification.

[0065] For the method embodiments, for the sake of simplicity, they are all described as a series of action combinations, but those skilled in the art should know that the present invention is not limited by the order of the actions described, because according to the present invention, some steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions and components involved are not necessarily required by the present invention.

[0066] The above is a detailed introduction to the coating material system and preparation method of the synergistic metal surface barrier layer and antioxidant layer provided by the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea; at the same time, for general technicians in this field, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A method for preparing a coating material system with a synergistic effect of a metal surface barrier layer and an anti-oxidation layer, characterized in that: The method comprises the following steps: S1, immersing the alloy substrate in a supersaturated solution of Y2O3 and / or CeO2, so that the surface of the alloy substrate is coated with a 2-3 μm thick crystal layer, and transferring it to an oven for drying to obtain a high-temperature alloy substrate with a first protective layer formed on the surface; S2. Under argon protection, heat treating the high temperature alloy substrate with the first protective layer formed on the surface at 300-500° C. for 2-5 hours; S3, after uniformly mixing the Ni-55Al-12Si-Y-Hf-Zr powder material, adding it into a mixed solution consisting of water, phosphoric acid, chromium oxide and magnesium oxide to prepare a slurry, and then uniformly spraying the slurry on the surface of the high-temperature alloy substrate treated by S2; Step 4: Under argon protection, the high-temperature alloy substrate treated with S3 is subjected to a heat treatment at 1000-1100° C. for 2-5 hours to obtain the coating material system.

2. The preparation method according to claim 1, characterized in that: In step S1, the drying temperature is 200° C. and the drying time is 30 minutes.

3. The preparation method according to claim 1, characterized in that: In step S2, the heat treatment temperature is 500°C and the heat treatment time is 2 hours.

4. The preparation method according to claim 1, characterized in that: In step S3, the Ni-55Al-12Si-Y-Hf-Zr powder material is a mixture of Ni powder, Al-12Si powder, Y2O3 powder, HfO and ZrO2 powder in a mass ratio of 5:4:3:1:

1.

5. The preparation method according to claim 1, characterized in that: In step S3, in the slurry, the mass volume ratio of the Ni-55Al-12Si-Y-Hf-Zr powder material to the mixed solution is 1g:1ml; In the mixed solution, the mass ratio of water, phosphoric acid, chromium oxide and magnesium oxide is 50:16.7:16.7:16.

7.

6. The preparation method according to claim 1, characterized in that: In step S3, the particle size of the Ni-55Al-12Si-Y-Hf-Zr powder material is micron-level.

7. The preparation method according to claim 1, characterized in that: In step S4, the heat treatment temperature is 1050° C. and the heat treatment time is 2 h.

8. A coating material system having a synergistic effect of a metal surface barrier layer and an anti-oxidation layer obtained by the preparation method according to any one of claims 1 to 7, characterized in that: The coating material system is composed of a first protective layer composed of Y2O3 and / or CeO2, and a second protective layer composed of Ni-55Al-12Si-Y-Hf-Zr; The total thickness of the coating material system is 30-40 μm, wherein the thickness of the first protective layer is 2-3 μm.

9. The coating material system according to claim 8, characterized in that: The high temperature alloy matrix includes: heat-resistant stainless steel 310S, high temperature alloy K456, Incoloy M956 or DZ640M.

10. The coating material system according to claim 9, characterized in that: The surface of the high-temperature alloy substrate is a surface of the high-temperature alloy substrate that has been degreased and sandblasted; The coating material system is used to protect the high-temperature alloy substrate to work stably at 1000-1100°C.

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