ODS steel with aluminum alloy coating and preparation method thereof

Abstract

The invention discloses an ODS steel with an aluminum alloy coating and a preparation method thereof. High-purity iron, high-purity chromium, high-purity titanium, nano-yttrium oxide powder and high-purity aluminum wire are used as raw materials. First, pure and defect-free 436 stainless steel is obtained by vacuum arc melting, water-cooled copper mold suction casting and hot rolling. Then, nano-yttrium oxide is introduced by a surface stir friction treatment process. Then, the ODS steel with an aluminum alloy coating is prepared by arc spraying and vacuum diffusion annealing. The aluminum alloyed ODS steel layer in the invention is prepared by combining surface stir friction treatment and arc spraying process to obtain fine matrix grains and nano-scale dispersed particles uniformly distributed in the matrix, which can be used for the preparation of the ODS aluminum alloy coating.

Description

Technical Field

[0001] The invention belongs to the technical field of corrosion-resistant metal structural materials in extreme service environments, and specifically relates to an ODS steel with an aluminum alloy coating and a preparation method thereof. Background Art

[0002] Due to the intensification of global warming, humans are in urgent need of seeking energy models that reduce carbon emissions to curb the greenhouse effect. Reducing and replacing fossil energy with renewable energy has become a widely accepted consensus to reduce carbon emissions. Nuclear energy has attracted great attention due to its advantages such as no carbon emissions, stability, and high efficiency during use. The fourth-generation nuclear reactor reference reactor represented by the lead-cooled fast reactor has become the first choice for the next generation of green energy for humans. Among them, the lead-cooled fast reactor uses lead / lead-bismuth alloy as a coolant, which has the characteristics of high safety, high economy, and high sustainability, and has great application potential; however, the corrosion problem of liquid alloy to structural materials needs to be solved urgently.

[0003] Stainless steel is widely used in all aspects of production and life because of its good mechanical properties, excellent corrosion resistance and low cost. The fuel cladding of lead-cooled fast reactors has a harsh service environment, is immersed in liquid lead-bismuth eutectic for a long time, and is subjected to high-dose neutron irradiation. Therefore, the cladding material must have excellent corrosion resistance and radiation resistance during service. Stainless steel has excellent corrosion resistance and low production cost, and has the potential to be used on a large scale in the core components of lead-cooled fast reactors. Limited by dissolution corrosion and severe radiation damage, commercial austenitic stainless steel cannot be used in the primary circuit of lead-cooled fast reactors; aluminum alloying on the surface of the original ferritic stainless steel can significantly improve its corrosion resistance, and introducing highly dispersed nano-scale oxide particles into the alloy matrix significantly improves the material's radiation resistance and high-temperature mechanical properties, making it one of the most competitive cladding materials. At present, there are many preparation methods for ODS steel, but most of them have problems such as high production cost, difficulty in large-scale production, and easy introduction of impurity elements, which hinder the large-scale application of ODS FeCrAl alloy in the nuclear industry. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide an ODS steel with an aluminum alloy coating and a preparation method thereof in view of the deficiencies in the above-mentioned prior art. An oxide dispersion strengthened steel with a fine grain structure of an aluminum alloy layer and fine oxide dispersed particles distributed in the matrix is ​​obtained through surface treatment. The radiation resistance and corrosion resistance of the alloy are improved while the mechanical properties are improved. The present invention is used to solve the technical problems of high production cost of ODS steel, difficulty in large-scale production, and easy introduction of impurity elements, and provides new ideas for the development of materials such as oxide dispersion strengthened (ODS) steel in nuclear reactors.

[0005] The present invention adopts the following technical solutions:

[0006] A method for preparing an ODS steel having an aluminum alloy coating comprises the following steps:

[0007] Yttrium oxide nanopowder, deionized water and polyvinyl alcohol are mixed to form Y 2 O 3 The slurry is scraped and coated on the surface of the steel plate and then vacuum dried for later use;

[0008] The coated surface of the vacuum dried steel plate is subjected to a surface stir friction treatment to obtain an ODS steel layer;

[0009] The ODS steel layer is sandblasted and cleaned in sequence, surface sprayed with 4N high-purity aluminum as a raw material, and then subjected to vacuum diffusion annealing to obtain an aluminum alloyed ODS steel layer with dispersed oxide particles.

[0010] Specifically, the steel plate is prepared by vacuum arc melting and water-cooled copper mold vacuum casting. Before the steel plate is coated, the surface of the steel plate is first polished and cleaned.

[0011] Specifically, Y 2 O 3 In the slurry, the mass fraction of nano yttrium oxide powder is 9%~11%, the mass fraction of polyvinyl alcohol is 19%~21%, and the mass fraction of deionized water is 69%~71%.

[0012] Specifically, Y 2 O 3 The slurry preparation process is as follows:

[0013] Add polyvinyl alcohol to deionized water, stir electromagnetically at 900-1100 rpm for 14-16 min, then add nano yttrium oxide powder, stir electromagnetically at 1400-1600 rpm for 25-30 min, and obtain Y 2 O 3 Slurry.

[0014] Specifically, the coating thickness is 50-100 μm, the vacuum drying temperature is 75-80° C., and the drying time is 50-60 min.

[0015] Specifically, grease is applied on the coating surface of the steel plate after vacuum drying, and the tool is pressed down by 150-200 μm, the tool speed is 300-600 rpm, and the feed rate is 50-100 mm / min to perform surface stir friction treatment.

[0016] Furthermore, the tool adopts a GCr15 alloy hemispherical tool with a radius of 6~8 mm.

[0017] Specifically, the sandblasting pressure is 0.4~0.6 MPa, the surface roughness Ra of the ODS steel layer after sandblasting is 1.8~2.4 μm, the arc voltage of spraying is 30~45 V, the arc current is 300~400 A, the spraying distance is 100~350 mm, and the surface thickness is 0.5~1.0 mm.

[0018] Specifically, the temperature of the vacuum diffusion annealing is 450-600° C., and the time is 4-16 h.

[0019] Another technical solution of the present invention is an ODS steel with an aluminum alloy coating, wherein, by weight percentage, Al: 4% to 6%, Y 2 O 3 : 0.50%~1.50%, Cr: 12.00%~14.00%, Ti: 0.50%~1.00%, Mn: 0.70~1.00%, and the rest are Fe and inevitable trace impurities.

[0020] Compared with the prior art, the present invention has at least the following beneficial effects:

[0021] A method for preparing an ODS steel with an aluminum alloy coating, through a stir friction treatment, while ensuring that the oxide dispersed particles are evenly distributed in the alloy layer, the matrix grains of the alloy layer are significantly refined; the ODS steel layer is aluminum alloyed by arc spraying and vacuum diffusion annealing process, which significantly improves the corrosion resistance of the ODS steel layer. The core point of the invention is the uniform distribution control of the dispersed particles, the refinement of the matrix grains of the ODS steel layer, and the aluminum alloying of the ODS steel layer, so as to be used for the preparation of the aluminum alloyed ODS steel layer.

[0022] Furthermore, vacuum arc melting is used to prepare the stainless steel plate substrate, which effectively avoids the introduction of impurity elements and the burning of raw materials, significantly improves the raw material utilization rate and the purity of the steel plate. The raw materials are cleaned and dried, which can not only avoid the introduction of impurity elements and minimize the defects and inclusions in the samples, but also effectively reduce the burning of raw materials during the smelting process and improve the utilization rate of raw materials.

[0023] Furthermore, the surface friction stir treatment was used to introduce nanoscale Y 2 O 3 Particles, effectively avoiding Y 2 O 3 The coarsening and agglomeration of Y 2 O 3 The uniform distribution of particles in the matrix and the refinement of the matrix structure.

[0024] Further, preparation of Y 2 O 3 Disperse the slurry evenly and apply it on the surface of the stainless steel plate to obtain Y2 O 3 Evenly distributed coating helps Y 2 O 3 Uniform introduction.

[0025] Furthermore, when the surface is subjected to friction stir treatment, the tool is pressed down, and the alloy layer undergoes severe plastic deformation and simultaneously 2 O 3 The coating layer is ground and mixed to promote Y 2 O 3 The coating layer is evenly distributed in the deformation layer, and grease is applied on the dry coating to reduce friction, which is beneficial to extend the service life of the tool.

[0026] Furthermore, a spherical high-alloy steel cutter is used to perform friction stir treatment on the surface of the steel plate, which not only ensures that the dispersed oxide particles are evenly distributed in the alloy layer, but also significantly refines the matrix grains of the alloy layer.

[0027] Furthermore, sandblasting the alloy surface before arc spraying can remove the oxide film and oil on the surface, reduce the introduction of impurities and defects, and arc spraying the sandblasted surface with high purity aluminum is beneficial to reduce the introduction of impurities and provide a diffusion source for aluminum alloying on the alloy surface.

[0028] Furthermore, after arc spraying and vacuum diffusion annealing, the mass fraction of aluminum in the ODS steel layer matrix is ​​4%~6%, and the average grain size is 20 μm.

[0029] In summary, the present invention adopts a process combining surface stir friction treatment and arc spraying to prepare the alloy layer, so that the alloy layer has fine grains and fine and uniform oxide dispersed particle distribution, making the material well used for the preparation of ODS aluminum-containing alloy.

[0030] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a process flow chart of the present invention. DETAILED DESCRIPTION

[0032] The technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] In the present invention, unless otherwise specified, all the embodiments and preferred implementation methods mentioned herein can be combined with each other to form a new technical solution.

[0034] In the present invention, unless otherwise specified, all technical features and preferred features mentioned herein can be combined with each other to form a new technical solution.

[0035] In the present invention, unless otherwise specified, percentage (%) or part refers to the weight percentage or weight part relative to the composition.

[0036] In the present invention, unless otherwise specified, the components or preferred components involved can be combined with each other to form a new technical solution.

[0037] In the present invention, unless otherwise specified, the numerical range "a-b" represents an abbreviation of any real number combination between a and b, where a and b are real numbers. For example, the numerical range "6-22" represents that all real numbers between "6-22" are listed in this document, and "6-22" is just an abbreviation of these numerical combinations.

[0038] The “range” disclosed in the present invention is in the form of a lower limit and an upper limit, which can be one or more lower limits, and one or more upper limits, respectively.

[0039] In the present invention, the term "and / or" used herein refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0040] In the present invention, unless otherwise specified, each reaction or operation step can be carried out sequentially or in accordance with the sequence. Preferably, the reaction method herein is carried out sequentially.

[0041] Unless otherwise specified, the professional and scientific terms used herein have the same meanings as those familiar to those skilled in the art. In addition, any method or material similar or equivalent to the described content may also be applied to the present invention.

[0042] The present invention provides an ODS steel with an aluminum alloy coating and a preparation method thereof. The steel is prepared by combining a surface stir friction treatment and an arc spraying process to obtain a structure with fine grains and uniformly distributed oxide dispersed particles, so as to obtain a steel layer with fine grain structure and fine dispersed particles distributed in the matrix, which is used for the preparation of ODS aluminum-containing alloys, and provides a new idea for the development of such materials in nuclear reactors.

[0043] In the ODS steel with aluminum alloy coating of the present invention, Al: 4% to 6%, Y 2 O 3: 0.50%~1.50%, Cr: 12.00%~14.00%, Ti: 0.50%~1.00%, Mn: 0.70~1.00%, and the rest are Fe and inevitable trace impurities.

[0044] The ODS steel with aluminum alloy coating includes a ferrite matrix and oxide dispersed particles distributed on the matrix. 2 O 3 The addition of can form uniformly distributed nano-scale dispersed particles, which can be used for the preparation of ODS aluminum-containing alloys.

[0045] The thickness of the ODS steel with aluminum alloy coating is 150~200 μm, the average particle size of the oxide dispersed particles is 20 μm, and the average particle size of the dispersed oxide particles is 60 nm.

[0046] See also Figure 1 The present invention provides an ODS steel with an aluminum alloy coating and a preparation method thereof, comprising the following steps:

[0047] S1, 436 stainless steel is prepared by vacuum arc melting and water-cooled copper mold vacuum casting, hot rolled into 20 mm thick steel plate, annealed and used;

[0048] S2, grinding and cleaning the surface of the 436 stainless steel plate prepared in step S1, mixing the nano yttrium oxide powder with deionized water and polyvinyl alcohol to form a slurry, applying the slurry on the surface of the steel plate with a scraper, and vacuum drying it for later use;

[0049] The steel plate was polished with sandpaper of 1000, 1500 and 2000 meshes in sequence, and ultrasonically cleaned with anhydrous ethanol and acetone in sequence; the slurry preparation steps were specifically as follows: nano yttrium oxide powder, polyvinyl alcohol and deionized water were weighed with a high-precision balance of 1 / 10,000 according to the mass fractions of 9%-11%, 19%-21% and 69%-71%, respectively, polyvinyl alcohol was first added to the deionized water, and electromagnetic stirring was performed at a speed of 900-1100 rpm for 14-16 min, and then nano yttrium oxide powder was added, and electromagnetic stirring was performed at a speed of 1400-1600 rpm for 25-30 min to obtain Y 2 O 3 Slurry;

[0050] Use a scraper to apply 50~100μm slurry, and then put it into a vacuum drying oven and dry it at 80℃ for 60 min.

[0051] S3, the coating with Y prepared in step S2 2 O 3 The slurry-coated steel plate was subjected to surface stir friction treatment using a GCr15 alloy hemispherical cutter to obtain an ODS steel layer;

[0052] The radius of the GCr15 alloy hemispherical tool is 6~8 mm;

[0053] During the surface friction stir treatment, grease was coated on the surface of the steel plate, the tool was pressed down by 150~200 μm, the tool speed was 300~600 rpm, and the feed rate was 100 mm / min.

[0054] S4. The ODS steel layer prepared in step S3 is sandblasted and cleaned in sequence, 4N high-purity aluminum is used as raw material, and is sprayed on its surface with an arc spray gun, and then vacuum diffusion annealing is performed to obtain an aluminum alloyed ODS steel layer with fine grains and uniformly distributed oxide dispersed particles.

[0055] The sandblasting pressure was 0.4-0.6 MPa, and the sand particles were brown corundum. The surface roughness Ra of the ODS steel layer was 1.8-2.4 μm after sandblasting, and then ultrasonic cleaning was carried out with anhydrous ethanol and acetone in turn.

[0056] The mass percentage of each component of 4N high-purity aluminum wire is 99.996% Al, and the rest are inevitable impurities. The diameter is 2 mm. The arc spraying process parameters are: arc voltage 30~45 V, arc current 300~400 A, spraying distance 100~350 mm, and surface thickness 0.5~1.0 mm;

[0057] The temperature of the vacuum diffusion annealing process is 450~600℃ and the time is 4~16 h.

[0058] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention described and shown in the drawings here can usually be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0059] Example 1

[0060] Preparation of toughened ODS steel with aluminum alloy coating

[0061] The present invention selects pure iron, pure chromium, ferromanganese, ferrotitanium, 4N6 grade pure aluminum wire, nano yttrium oxide powder and the like as raw materials. A nuclear grade 436 steel substrate is obtained by vacuum arc melting, vacuum copper mold suction casting and thermal deformation process; the nano yttrium oxide powder is introduced into the substrate by stir friction treatment to obtain an ODS steel layer; and an aluminum-containing ODS steel coating is obtained by arc spraying and vacuum heat treatment annealing.

[0062] The specific preparation process of the present invention is as follows:

[0063] S1. According to the composition ratio requirements, the cast alloy was prepared by vacuum arc melting and water-cooled copper mold vacuum suction casting. After hot rolling and annealing, a 436 stainless steel substrate with a thickness of 20 mm was obtained.

[0064] S2, the surface of the 436 stainless steel plate prepared in step S1 is polished with sandpaper of 1000, 1500 and 2000 meshes, and ultrasonically cleaned with anhydrous ethanol and acetone, respectively, and the nano-yttrium oxide powder, polyvinyl alcohol and deionized water are weighed with a high-precision balance of 1 / 10,000 according to the mass fraction of 9%, 19% and 70%, respectively, firstly polyvinyl alcohol is added to the deionized water, and the nano-yttrium oxide powder is added after electromagnetic stirring at a speed of 1100 rpm for 14 min, and then the slurry is obtained after electromagnetic stirring at a speed of 1600 rpm for 30 min, and a slurry coating with a thickness of 50 μm is obtained by scraping with a scraper, and then the slurry is placed in a vacuum drying oven and dried at 80° C. for 60 min;

[0065] S3, the coating with Y prepared in step S2 2 O 3 The surface of the slurry-coated steel plate was coated with graphene grease, and the coating surface was subjected to surface stir friction treatment with a GCr15 alloy hemispherical tool with a radius of 6 mm, a downward pressure of 150 μm, a rotation speed of 600 rpm and a feed rate of 100 mm / min to obtain an ODS steel layer;

[0066] S4. Use brown corundum sand to sandblast the ODS steel layer prepared in step S3 at a pressure of 0.41 MPa to make the surface roughness Ra of 1.9 μm, and use anhydrous ethanol and acetone for ultrasonic cleaning in turn. Use 4N6 grade high-purity aluminum wire with a diameter of 2 mm as the raw material, and use an arc spray gun to spray on its surface at an arc voltage of 32 V and an arc current of 320 A with a spraying distance of 100 mm to obtain a 0.6 mm thick coating, and then vacuum diffusion annealing at 450°C for 16 h to obtain ODS steel with an aluminum alloy coating.

[0067] The ODS steel with aluminum alloy coating obtained in this embodiment has fine grains and evenly distributed oxide dispersed particles, forming a composite alloy structure with an aluminum alloy solid solution strengthened matrix and an oxide dispersed phase with excellent high temperature stability, which significantly improves the mechanical properties of the alloy while taking into account certain corrosion resistance and radiation resistance.

[0068] Example 2

[0069] Preparation of corrosion-resistant ODS steel with aluminum alloy coating

[0070] The present invention selects pure iron, pure chromium, ferromanganese, ferrotitanium, 4N6 grade pure aluminum wire, nano yttrium oxide powder and the like as raw materials. A nuclear grade 436 steel substrate is obtained by vacuum arc melting, vacuum copper mold suction casting and thermal deformation process; the nano yttrium oxide powder is introduced into the substrate by stir friction treatment to obtain an ODS steel layer; and an aluminum-containing ODS steel coating is obtained by arc spraying and vacuum heat treatment annealing.

[0071] The specific preparation process of the present invention is as follows:

[0072] S1. According to the composition ratio requirements, the cast alloy was prepared by vacuum arc melting and water-cooled copper mold vacuum suction casting. After hot rolling and annealing, a 436 stainless steel substrate with a thickness of 15 mm was obtained.

[0073] S2, the surface of the 436 stainless steel plate prepared in step S1 is polished with sandpaper of 1000, 1500 and 2000 meshes, and ultrasonically cleaned with anhydrous ethanol and acetone, respectively, and nano-yttrium oxide powder, polyvinyl alcohol and deionized water are weighed with a high-precision balance of 1 / 10,000 according to the mass fraction of 11%, 20% and 69%, respectively, firstly polyvinyl alcohol is added to the deionized water, and electromagnetic stirring is performed at a speed of 1000 rpm for 15 min, and then nano-yttrium oxide powder is added, and electromagnetic stirring is performed at a speed of 1500 rpm for 27 min to obtain a slurry, and a slurry coating with a thickness of 100 μm is obtained by scraping with a scraper, and then the slurry is placed in a vacuum drying oven at 77° C. and dried for 55 min;

[0074] S3, the coating with Y prepared in step S2 2 O 3 The surface of the slurry-coated steel plate was coated with graphene grease, and the coating surface was subjected to surface stir friction treatment with a GCr15 alloy hemispherical tool with a radius of 8 mm, a downward pressure of 200 μm, a rotation speed of 300 rpm and a feed rate of 50 mm / min to obtain an ODS steel layer;

[0075] S4. Use brown corundum sand to sandblast the ODS steel layer prepared in step S3 at a pressure of 0.50 MPa to make the surface roughness Ra 2.5 μm, and use anhydrous ethanol and acetone ultrasonic cleaning in turn. Use 4N6 grade high-purity aluminum wire with a diameter of 2 mm as the raw material, and use an arc spray gun to spray on its surface at an arc voltage of 40 V and an arc current of 350 A with a spraying distance of 150 mm to obtain a 1.0 mm thick coating, and then vacuum diffusion annealing at 600°C for 12 h to obtain ODS steel with an aluminum alloy coating.

[0076] The ODS steel with aluminum alloy coating obtained in this embodiment has a deep aluminum thermal diffusion depth and excellent corrosion resistance. 2 O 3 Dispersed particles improve the mechanical properties of the alloy and compensate for the softening of ferritic steel at higher aluminum contents.

[0077] Example 3

[0078] Preparation of ODS steel coating samples

[0079] The present invention selects pure iron, pure chromium, ferromanganese, ferrotitanium, 4N6 grade pure aluminum wire, nano yttrium oxide powder and the like as raw materials. A nuclear grade 436 steel substrate is obtained by vacuum arc melting, vacuum copper mold suction casting and thermal deformation process; the nano yttrium oxide powder is introduced into the substrate by stir friction treatment to obtain an ODS steel layer; and an aluminum-containing ODS steel coating is obtained by arc spraying and vacuum heat treatment annealing.

[0080] The specific preparation process of the present invention is as follows:

[0081] S1. According to the composition ratio requirements, the cast alloy was prepared by vacuum arc melting and water-cooled copper mold vacuum suction casting. After hot rolling and annealing, a 436 stainless steel substrate with a thickness of 20 mm was obtained.

[0082] S2, the surface of the 436 stainless steel plate prepared in step S1 is polished with sandpaper of 1000, 1500 and 2000 meshes, and ultrasonically cleaned with anhydrous ethanol and acetone, respectively, and nano-yttrium oxide powder, polyvinyl alcohol and deionized water are weighed with a high-precision balance of 1 / 10,000 according to the mass fraction of 10%, 21% and 69%, respectively, firstly polyvinyl alcohol is added to the deionized water, and electromagnetic stirring is performed at a speed of 900 rpm for 16 min, and then nano-yttrium oxide powder is added, and electromagnetic stirring is performed at a speed of 1400 rpm for 25 min to obtain a slurry, and a slurry coating with a thickness of 90 μm is obtained by scraping with a scraper, and then placed in a vacuum drying oven and dried at 80° C. for 60 min;

[0083] S3, the coating with Y prepared in step S2 2 O 3The surface of the slurry-coated steel plate was coated with graphene grease, and the coating surface was subjected to surface stir friction treatment with a GCr15 alloy hemispherical tool with a radius of 8 mm, a downward pressure of 50 μm, a rotation speed of 500 rpm and a feed rate of 100 mm / min to obtain an ODS steel layer;

[0084] S4. Use brown corundum sand to sandblast the ODS steel layer prepared in step S3 at a pressure of 0.41 MPa to make the surface roughness Ra 2.1 μm, and use anhydrous ethanol and acetone ultrasonic cleaning in turn. Use 4N6 grade high-purity aluminum wire with a diameter of 2 mm as the raw material, and use an arc spray gun to spray on its surface at an arc voltage of 40 V and an arc current of 375 A with a spraying distance of 250 mm to obtain a 1.0 mm thick coating, and then vacuum diffusion annealing at 530°C for 8 h to obtain ODS steel with an aluminum alloy coating.

[0085] The ODS steel with aluminum alloy coating obtained in this embodiment has fine grains and evenly distributed oxide dispersed particles. The aluminum diffusion layer further improves the corrosion resistance of the alloy, and has good mechanical properties, corrosion resistance and radiation resistance.

[0086] In summary, the present invention provides an ODS steel with an aluminum alloy coating and a preparation method thereof, so that the alloy has fine grains and uniform nano-scale dispersed particle distribution, and can be used for the preparation of ODS aluminum-containing alloys.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing ODS steel with an aluminum alloy coating, characterized in that: The following steps are involved: Mix nano yttrium oxide powder, deionized water and polyvinyl alcohol to make Y2O3 slurry, apply it on the surface of steel plate, and set aside after vacuum drying. In the Y2O3 slurry, the mass fraction of nano yttrium oxide powder is 9%~11%, the mass fraction of polyvinyl alcohol is 19%~21%, and the mass fraction of deionized water is 69%~71%. The coating surface of the vacuum-dried steel plate was subjected to a surface stir friction treatment, grease was applied to the coating surface of the vacuum-dried steel plate, the tool was pressed down by 150-200 μm, the tool speed was 300-600 rpm, the feed rate was 50-100 mm / min, and the surface stir friction treatment was performed to obtain an ODS steel layer; The ODS steel layer was sandblasted and cleaned in sequence, and 4N high-purity aluminum was used as the raw material for surface spraying. Then, vacuum diffusion annealing was performed to obtain an aluminum alloyed ODS steel layer with dispersed oxide particles. The sandblasting pressure was 0.4~0.6 MPa. The surface roughness Ra of the ODS steel layer after sandblasting was 1.8~2.4 μm. The arc voltage of spraying was 30~45 V, the arc current was 300~400 A, the spraying distance was 100~350 mm, the surface thickness was 0.5~1.0 mm, the vacuum diffusion annealing temperature was 450~600℃, and the time was 4~16 h.

2. The method for preparing ODS steel with aluminum alloy coating according to claim 1, characterized in that: The steel plate is prepared by vacuum arc melting and water-cooled copper mold vacuum suction casting. Before scraping and coating, the surface of the steel plate is polished and cleaned.

3. The method for preparing ODS steel with aluminum alloy coating according to claim 1, characterized in that: The preparation process of Y2O3 slurry is as follows: Add polyvinyl alcohol to deionized water, perform electromagnetic stirring at a speed of 900-1100 rpm for 14-16 min, then add nano yttrium oxide powder, and then perform electromagnetic stirring at a speed of 1400-1600 rpm for 25-30 min to obtain Y2O3 slurry.

4. The method for preparing ODS steel with aluminum alloy coating according to claim 1, characterized in that: The coating thickness is 50~100μm, the vacuum drying temperature is 75~80℃, and the time is 50~60 min.

5. The method for preparing ODS steel with aluminum alloy coating according to claim 1, characterized in that: In the surface stir friction treatment, the tool used was a GCr15 alloy hemispherical tool with a radius of 6 to 8 mm.

6. An ODS steel with an aluminum alloy coating, characterized in that: The ODS steel having an aluminum alloy coating is prepared according to the preparation method of any one of claims 1 to 5, wherein, by weight percentage, Al: 4%~6%, Y2O3: 0.50%~1.50%, Cr: 12.00%~14.00%, Ti: 0.50%~1.00%, Mn: 0.70~1.00%, and the rest is Fe and inevitable trace impurities.

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