A coating material system and a preparation method of a metal surface barrier layer and an oxidation-resistant layer

Abstract

The application provides a coating material system with synergistic effect of a barrier layer and an oxidation-resistant layer on a metal surface, which 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 application fully utilizes 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, so that the coating material system can realize long-term oxidation resistance of a hot end part of a gas turbine at 1000-1100 DEG C. The application also provides a preparation method of the coating material system with synergistic effect of a barrier layer and an oxidation-resistant layer on a metal surface. The method uses a supersaturated solution immersion method to prepare the first protective layer composed of Y2O3 and / or CeO2, and further uses a slurry method to prepare the second protective layer composed of Ni-55Al-12Si-Y-Hf-Zr on the basis of the first protective layer, so that the coating material system is uniform and dense, and the uniformity of the coating material system can be ensured even for a hot end part with a complex inner cavity and an outer shape structure at a small angle.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of composite coating, in particular to a coating material system with synergistic effect of barrier layer and oxidation-resistant layer on metal surface and a preparation method thereof. BACKGROUND

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

[0003] However, in long-term high-temperature service, Al elements will be consumed continuously. There is also interdiffusion between the oxidation-resistant 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 adversely affect the high-temperature durability of the substrate material, resulting in the alloy material not meeting the requirement of long-term stable oxidation resistance for more than 5000 hours.

[0004] In addition, for complex inner cavities and outer shape structures such as small-angle, thermal spraying, CVD, PVD and other technologies cannot achieve uniform preparation of the coating. SUMMARY

[0005] In view of the above problems in the prior art, the present application provides a coating material system with synergistic effect of barrier layer and oxidation-resistant layer on metal surface, which adopts a coating structure of surface diffusion barrier layer + oxidation-resistant layer to meet the requirement of long-term oxidation resistance of metal substrate for thousands of hours. The present application also provides a preparation method of the coating material system with synergistic effect of barrier layer and oxidation-resistant layer on metal surface to achieve uniform preparation of the coating on the substrate surface.

[0006] The specific application contents are as follows:

[0007] In a first aspect, the present application provides a preparation method of a coating material system with synergistic effect of barrier layer and oxidation-resistant layer on metal surface, which comprises the following steps:

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

[0009] S2, heat treating the alloy substrate with the first protective layer on the surface at 300-500℃ for 2-5h under argon protection;

[0010] S3, after the Ni-55Al-12Si-Y-Hf-Zr powder material is uniformly mixed, the powder material is added into a mixed solution composed of water, phosphoric acid, chromium oxide and magnesium oxide, a slurry is prepared, and then the slurry is uniformly sprayed on the alloy substrate surface treated in S2;

[0011] Step 4: under the protection of argon, the alloy substrate treated in S3 is subjected to heat treatment at 1000-1100℃ for 2-5h to obtain the coating material system.

[0012] Optionally, in step S1, the temperature of the drying treatment is 200℃, and the time of the drying treatment is 30min.

[0013] Optionally, in step S2, the temperature of the heat treatment is 500℃, and the time of the heat treatment is 2h.

[0014] Optionally, in step S3, the Ni-55Al-12Si-Y-Hf-Zr powder material is mixed by Ni, Al-12Si, Y2O3, HfO and ZrO2 with 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 1g:1ml.

[0016] In the mixed solution, the mass ratio of the 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 micron level.

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

[0019] In a second aspect, the present application provides a coating material system with synergistic effect of metal surface barrier layer and oxidation resistant layer obtained by the preparation method of the first aspect, and 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 30-40μm, and the thickness of the first protective layer is 2-3μm.

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

[0022] Optionally, the high-temperature alloy substrate surface is a high-temperature alloy substrate surface after oil removal and sand blasting treatment.

[0023] The coating material system is used for protecting the high-temperature alloy substrate to work stably at 1000-1100℃.

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

[0025] The present application provides a coating material system with synergistic effect of metal surface barrier layer and oxidation-resistant layer, which 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 application fully utilizes 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, so that the coating material system can realize long-term oxidation resistance of the hot end part of the gas turbine at 1000-1100℃.

[0026] The present application provides another preparation method of the coating material system with synergistic effect of metal surface barrier layer and oxidation-resistant layer. The method uses supersaturated solution immersion method to prepare the first protective layer composed of Y2O3 and / or CeO2, and further uses slurry method to prepare the second protective layer composed of Ni-55Al-12Si-Y-Hf-Zr on the basis of the first protective layer, so that the prepared coating material system is uniform and dense. Even for the hot end part with complex inner cavity and outer shape structure at a small angle, the uniformity of the prepared coating material system can be ensured. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0028] Figure 1 A flow chart of the preparation method of the coating material system provided by the embodiment of the present application is shown. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way limiting on the application or its applications or uses. Based on the embodiments in the present application, any person skilled in the art obtains any product same or similar to the present application under the inspiration of the present application or combines the present application with other prior art features, which falls within the protection scope of the present application. In addition, all other embodiments obtained by the ordinary skilled in the art without carrying out creative labor belong to the protection scope of the present application.

[0030] If the specific experimental steps or conditions are not indicated in the embodiments, the operation or conditions can be carried out according to the conventional experimental steps described in the prior art in the field. If the manufacturers of the reagents and other instruments are not indicated, the reagents are conventional reagent products that can be obtained by purchase. In addition, the drawings are only schematic diagrams of the embodiments of the present application, and are not necessarily drawn to scale. The same reference signs in the drawings represent the same or similar parts, and thus repeated description thereof will be omitted. Some block diagrams shown in the drawings are functional entities, and do not necessarily correspond to physically or logically independent entities.

[0031] The technologies, methods and devices known to the person skilled in the relevant art can not be discussed in detail, but under appropriate circumstances, the technologies, methods and devices should be regarded as part of the present application.

[0032] In the description of the present application, it should be understood that the use of the words "first", "second" and the like to qualify elements is only for the convenience of distinguishing the corresponding elements, and the above words have no special meaning unless otherwise stated, and therefore cannot be understood as limiting the protection scope of the present application.

[0033] In addition, the technical features involved in different embodiments of the present application 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 application provides a preparation method of a coating material system with synergistic effect of a metal surface barrier layer and an oxidation-resistant layer, Figure 1 A flow chart of the preparation method of the coating material system provided by the embodiments of the present application is shown as follows, Figure 1 The method comprises the following steps:

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

[0036] S2, heat treating the alloy substrate with the first protective layer on the surface at 300-500℃ for 2-5h under argon protection;

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

[0038] Step 4: heat treating the alloy substrate treated in S3 at 1000-1100℃ for 2-5h under argon protection to obtain the coating material system.

[0039] In specific implementation, the first protective layer composed of Y2O3 and / or CeO2 is prepared on the surface of the high-temperature alloy by means of supersaturated solution impregnation. Y2O3 and / or CeO2 plays an important role in preventing atomic or ionic diffusion due to its chemical stability and lattice structure characteristics. As the protective coating directly contacting the surface of the high-temperature alloy, Y2O3 and / or CeO2 can effectively inhibit the diffusion of metal elements in the alloy substrate and has high diffusion barrier capacity. 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 reaction rate of metal elements. By hindering the mutual penetration of metal elements, the mutual diffusion in the alloy substrate can be effectively reduced. Therefore, the first protective layer composed of Y2O3 and / or CeO2 has high melting point and thermal stability, can maintain good chemical stability and structural stability, and protects the alloy substrate from the influence of element diffusion and reaction in high-temperature environment.

[0040] In specific implementation, the supersaturated solution impregnation method can realize uniform preparation of the first protective layer on the hot end component with complex inner cavity and outer shape structure at a small angle.

[0041] In specific implementation, the first protective layer prepared by the supersaturated solution impregnation method is heat treated at 300-500℃ for 2-5h under argon protection, so that the first protective layer obtains sufficient shrinkage energy for further densification and improves the bonding strength with the substrate; avoids the problems of porosity and coating cracks during later high-temperature use, and affects the quality of the finally obtained coating system. The preferred heat treatment temperature is 500℃ and the time is 2h.

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

[0043] In particular implementation, the particle size of the Ni-55Al-12Si-Y-Hf-Zr powder material selected in the embodiment is micron level, so as to ensure the uniformity of the slurry spraying. After the slurry is sprayed on the surface of the first protective layer, high-temperature heat treatment is performed to make the Ni-55Al-12Si-Y-Hf-Zr powder material and the first protective layer realize full metallurgical bonding. The preferred heat treatment temperature is 1050℃, and the time is 2h.

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

[0045] Further, the second protective layer composed of Ni-55Al-12Si-Y-Hf-Zr further protects the first protective layer and reduces the damage of the external environment to the first protective layer. In addition, the oxidation-resistant and corrosion-resistant ability of the Ni-55Al-12Si-Y-Hf-Zr material is outstanding, and the combination of the protective layer and the Y2O3 and / or CeO2 coating can further improve the heat corrosion resistance and wear resistance, further improve the thermal stability of the whole coating, enhance the oxidation resistance, heat corrosion resistance, improve the hardness and wear resistance, and prevent the coating from cracking and peeling off during high-temperature work. Such combination can provide a stronger protective layer for the high-temperature alloy and prolong the service life.

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

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

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

[0049] Example 1

[0050] The nickel-based high-temperature alloy K465 alloy has high creep resistance, fatigue resistance and high temperature resistance. The material is used as the high-temperature alloy substrate material, and is fixed by a fixed clamping device.

[0051] The high-temperature alloy substrate material is placed in a supersaturated yttrium oxide and cerium oxide mixed solution for 2 min through sand blasting and cleaning treatment of the surface, so that yttrium oxide and cerium oxide grains are uniformly attached to the surface of the high-temperature alloy substrate, and then the high-temperature alloy substrate material is placed in an oven for drying treatment at 200 DEG C for 30 min.

[0052] The high-temperature alloy substrate material after the drying treatment is subjected to heat treatment at 500 DEG C for 2 hours under an argon protective gas, so that a dense first protective layer composed of Y2O3 or CeO2 is formed on the surface of the high-temperature alloy substrate. At the same time, the heat treatment improves the bonding strength of the coating and the substrate.

[0053] Ni, Al-12Si, Y2O3, HfO and ZrO2 with a mass ratio of 5:4:3:1:1 are mixed to form a Ni-55Al-12Si-Y-Hf-Zr powder material, which is added to a mixed solution formed by mixing water, phosphoric acid, chromium oxide and magnesium oxide with a mass ratio of 50:16.7:16.7:16.7 to prepare a slurry, which is uniformly sprayed on the surface of the first protective layer, and after drying, heat treatment at 1050 DEG C for 2 hours is performed to obtain a 30-40 micrometer coating system.

[0054] Example 2

[0055] The M956 alloy has high endurance strength and excellent oxidation resistance and corrosion resistance at high temperature, and is widely used as a hot end part of an advanced aero-engine working at 1000-1200 DEG C and a thermal protection part of an industrial furnace working at more than 1300 DEG C. The material is used as the high-temperature alloy substrate material, and is fixed by a fixed clamping device.

[0056] The high-temperature alloy substrate material is placed in a supersaturated yttrium oxide mixed solution for 2 min through sand blasting and cleaning treatment of the surface, so that yttrium oxide grains are uniformly attached to the surface of the high-temperature alloy substrate, and then the high-temperature alloy substrate material is placed in an oven for drying treatment at 200 DEG C for 30 min.

[0057] The high-temperature alloy base material after the above drying treatment is heat treated at 500°C for 2 hours under argon protective gas, so that a dense first protective layer composed of Y2O3 is formed on the surface. At the same time, the heat treatment improves the bonding strength of the coating and the base.

[0058] Ni, Al-12Si, Y2O3, HfO and ZrO2 powders in a mass ratio of 5:4:3:1:1 are weighed and mixed to form a Ni-55Al-12Si-Y-Hf-Zr powder material, which is 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 is uniformly sprayed on the surface of the first protective layer, dried, and then heat treated at 1050°C for 2 hours, to obtain a 30-40 micron coating system.

[0059] Example 3

[0060] The heat-resistant stainless steel 310S is an austenitic stainless steel with good oxidation resistance and corrosion resistance, and has good creep strength due to a high percentage of chromium and nickel, can work continuously at high temperature, and has good high-temperature resistance. The material is used as a high-temperature alloy base material, which is fixed by a fixed clamping device.

[0061] The high-temperature alloy base material is placed in a supersaturated cerium oxide mixed solution for 2 minutes through sandblasting and cleaning treatment on the surface; cerium oxide grains are uniformly attached to the surface of the high-temperature alloy base, and then dried in an oven at 200°C for 30 minutes.

[0062] The high-temperature alloy base material after the above drying treatment is heat treated at 500°C for 2 hours under argon protective gas, so that a dense first protective layer composed of Y2O3 is formed on the surface. At the same time, the heat treatment improves the bonding strength of the coating and the base.

[0063] Ni, Al-12Si, Y2O3, HfO and ZrO2 powders in a mass ratio of 5:4:3:1:1 are weighed and mixed to form a Ni-55Al-12Si-Y-Hf-Zr powder material, which is 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 is uniformly sprayed on the surface of the first protective layer, dried, and then heat treated at 1050°C for 2 hours, to obtain a 30-40 micron coating system.

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

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

[0066] The above describes in detail the coating material system and preparation method of the metal surface barrier layer and oxidation-resistant layer provided by the present application. The principles and implementation manners of the present application are described by applying specific examples in this paper. The above embodiment description is only used to help understand the method of the present application and its core idea; at the same time, for those skilled in the art, according to the idea of the present application, the specific implementation manner and application range will be changed, and the above description should not be understood as a limitation of the present application.

Claims

1. A method for producing a coating material system for the synergistic effect of a barrier layer and an oxidation-resistant layer on a metal surface, characterized in that The method comprises the following steps: S1, dipping the alloy matrix into a supersaturated solution of Y2O3 and / or CeO2, so that a 2-3 μm thick crystal layer is wrapped on the surface of the alloy matrix, and the alloy matrix is transferred to an oven for drying treatment to obtain a high-temperature alloy matrix with a first protective layer on the surface; S2, under the protection of argon, the high-temperature alloy matrix with the first protective layer on the surface is subjected to heat treatment at 300-500°C for 2-5h; S3, after uniformly mixing the Ni-55Al-12Si-Y-Hf-Zr powder material, it is added to a mixed solution composed of water, phosphoric acid, chromium oxide and magnesium oxide to prepare a slurry, and then the slurry is uniformly sprayed on the surface of the high-temperature alloy matrix treated in S2; Step 4: under the protection of argon, the high-temperature alloy matrix treated in S3 is subjected to heat treatment at 1000-1100°C for 2-5h to obtain the coating material system.

2. The production method according to claim 1, characterized by, In step S1, the drying treatment temperature is 200°C, and the drying treatment time is 30min.

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 2h.

4. The method of claim 1, wherein, In step S3, the Ni-55Al-12Si-Y-Hf-Zr powder material is mixed by Ni powder, Al-12Si powder, Y2O3 powder, HfO and ZrO2 powder with a mass ratio of 5:4:3:1:

1.

5. The preparation method according to claim 1, characterized in that, In step S3, the mass-volume ratio of the Ni-55Al-12Si-Y-Hf-Zr powder material to the mixed solution in the slurry 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 method of claim 1, wherein, 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 2h.

8. The coating material system of the synergistic effect of the metal surface barrier layer and the oxidation resistant layer obtained by the preparation method of any one of claims 1-7, 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, and the thickness of the first protective layer is 2-3 μm.

9. The coating material system of claim 8, wherein, The high-temperature alloy matrix comprises heat-resistant stainless steel 310S, high-temperature alloy K456, Incoloy M956 or DZ640M.

10. The coating material system of claim 9, wherein, The surface of the high-temperature alloy matrix is the surface of the high-temperature alloy matrix after oil removal and sand blasting treatment; The coating material system is used to protect the high-temperature alloy matrix to work stably at 1000-1100°C.

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