A high-temperature, high-strength molybdenum alloy with in-situ self-healing antioxidant film and its preparation method
By combining matrix alloying and surface modification, a molybdenum alloy with a self-healing antioxidant coating was prepared, which solved the problem of poor oxidation performance of molybdenum alloys at high temperatures. This improved the high-temperature antioxidant performance and service stability under extreme conditions, making it suitable for aerospace, nuclear industry and other fields.
Patent Information
- Application Number
- CN202610239549.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-02-28
- Publication Date
- 2026-05-26
AI Technical Summary
Existing molybdenum alloys have poor high-temperature oxidation resistance, especially in the 600℃-800℃ range where they are prone to Pesting oxidation. The oxide layer is loose and porous, which cannot provide effective protection. Furthermore, existing coating technologies suffer from problems such as mismatched coefficients of thermal expansion, high brittleness, and high cost, making it difficult to meet the service requirements in extreme high-temperature and oxygen-containing environments.
A molybdenum alloy containing REmTaOn, (Mo, Ta)Si2, and (Mo, Ta)5Si3 coatings was prepared by combining matrix alloying and surface modification. The high-temperature oxidation resistance was enhanced by forming a self-healing anti-oxidation film on the surface of the molybdenum alloy, and the matrix properties were regulated by matrix alloying to reduce the difference in thermal expansion coefficients between the coating and the matrix, thus forming a dense interfacial bond.
It forms a dense, self-healing oxide film at high temperatures, effectively preventing oxides from diffusing into the substrate, improving the coating's thermal shock resistance, and adapting to service stability under extreme conditions. It has the advantages of simple process and high cost-effectiveness, and is suitable for aerospace, nuclear industry and other fields.
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Abstract
Description
Technical Field
[0001] This invention relates to the field of high-temperature alloy thermal protection technology, specifically to a high-temperature, high-strength molybdenum alloy with an in-situ self-healing antioxidant film and its preparation method. Background Technology
[0002] Molybdenum alloys, due to their excellent high-temperature properties, including a melting point as high as 2623℃, outstanding high-temperature strength, low coefficient of thermal expansion, and good thermal and electrical conductivity, are widely recognized as core candidate structural materials for extreme high-temperature environments. They have irreplaceable application value in key equipment such as hot-end components of high thrust-to-weight ratio aero-engines, rocket nozzles, the first wall of nuclear fusion devices, high-temperature heating elements, and glass processing molds. However, molybdenum alloys have extremely poor high-temperature oxidation resistance, an inherent defect that severely restricts their engineering applications in oxygen-containing high-temperature environments, becoming a core technological bottleneck that urgently needs to be overcome in the field of molybdenum alloy materials.
[0003] Existing research indicates that the high-temperature oxidation failure of molybdenum alloys exhibits a clear temperature dependence and mechanism specificity: significant oxidation reactions begin to occur around 600℃; when the temperature is in the 600℃-800℃ range, the "Pesting" catastrophic oxidation phenomenon is easily triggered. During this process, the oxidation product generated by the reaction of molybdenum and oxygen is primarily molybdenum trioxide (MoO3), which has a melting point of only 795℃ and a high vapor pressure. Within the aforementioned temperature range, it readily melts and rapidly volatilizes, resulting in a persistently loose and porous oxide layer that cannot form an effective protective barrier. This allows oxygen to continuously diffuse into the alloy matrix, ultimately causing the molybdenum alloy matrix to disintegrate and fail. When the temperature rises above 1000℃, the volatilization rate of MoO3 further accelerates, and the intensity of the oxidation reaction and the alloy loss rate increase simultaneously. Even if elements such as silicon and aluminum are added through alloying to try to improve the protective effect by generating oxidation products such as silicon dioxide (SiO2) and aluminum oxide (Al2O3), cracks are easily generated at low temperatures due to the mismatch of thermal expansion coefficients between the oxide layer and the substrate, and at high temperatures, pores are formed due to the volatilization of MoO3. It is still difficult to achieve long-term and stable anti-oxidation protection.
[0004] To address the aforementioned oxidation problem, various technical solutions have been proposed in the existing technology, but all of them have insurmountable drawbacks: Firstly, in terms of alloying strategies, although adding elements such as silicon, aluminum, and chromium can improve the oxidation resistance to a certain extent, it will lead to a significant decrease in the room temperature toughness and processing and forming performance of the molybdenum alloy matrix, making it impossible to balance high-temperature protection performance with the mechanical properties required for engineering applications; although oxide dispersion strengthening can improve the high-temperature strength of the alloy, its inhibitory effect on oxidation reaction is very limited. Secondly, regarding coating protection technology, as the current mainstream protection method, existing coating systems still face core technical challenges: silicide coatings (such as MoSi2 coatings) can form a dense SiO2 protective film at high temperatures, but they are prone to Pesting oxidation failure in low-temperature ranges, and the mismatch in thermal expansion coefficients between the coating and the substrate can easily lead to coating peeling. At the same time, interdiffusion at the interface can weaken the protective performance; modified composite coatings such as Si-Hf and Si-Zr can improve coating stability by generating high-melting-point ZrO2 and HfO2 reinforcing phases, but they have problems such as complex preparation processes and high production costs, making it difficult to achieve large-scale engineering applications; aluminide coatings are prone to failure in high-temperature environments above 1500℃, while ceramic coatings have inherent defects such as high brittleness and poor thermal shock resistance, neither of which can meet the long-term protection requirements under complex and extreme working conditions.
[0005] In summary, existing molybdenum alloy anti-oxidation technologies cannot effectively address core requirements such as low-temperature resistance to pyrolysis, long-term high-temperature protection, stable coating-substrate interface bonding, and excellent thermal shock resistance. These technologies are ill-suited to the service requirements of molybdenum alloy components in aerospace, energy, and nuclear industries under extreme high-temperature and oxygen-containing conditions. Therefore, developing a molybdenum alloy anti-oxidation technology that balances protective performance, mechanical compatibility, and engineering application feasibility is crucial for overcoming the application bottlenecks of molybdenum alloys and improving the reliability and service life of high-end equipment. This remains a pressing technical challenge for those skilled in the art. Summary of the Invention
[0006] The purpose of this invention is to at least solve one of the technical problems existing in the prior art, and to provide a high-temperature, high-strength, oxidation-resistant molybdenum alloy and its preparation method.
[0007] The technical solution of the present invention is as follows: A high-temperature, high-strength, oxidation-resistant molybdenum alloy with an in-situ self-healing antioxidant film, comprising: a molybdenum alloy matrix, wherein the molybdenum alloy matrix comprises: 10-25 wt% Ta, 3.0-10 wt% rare earth elements, and the balance being Mo. The tungsten alloy, due to the addition of tantalum which provides solid solution strengthening, and the second-phase particles which pin the grain boundaries, enhances the elastic modulus and rigidity of the tungsten alloy, further strengthening its high-temperature strength.
[0008] As a preferred embodiment of the present invention, it further includes an antioxidant coating formed on the surface of a molybdenum alloy substrate, said antioxidant coating containing at least RE. m TaO n phase, (Mo, Ta)Si2 phase and (Mo, Ta)5Si3 phase.
[0009] As a preferred embodiment of the present invention, the antioxidant coating is at least a two-layer structure, and its outer layer has at least RE m TaO n The inner layer contains at least one (Mo, Ta)Si2 phase and at least one (Mo, Ta)5Si3 phase.
[0010] As a preferred embodiment of the present invention, the thickness of the antioxidant coating is 110-130 μm.
[0011] This invention also discloses a method for preparing a high-temperature, high-strength, antioxidant molybdenum alloy with an in-situ self-healing antioxidant film, wherein Mo, Ta and rare earth elements are mixed in proportion, and then pressed and sintered to obtain a molybdenum alloy matrix.
[0012] As a preferred embodiment of the present invention, the following steps are also included: Weigh out a certain amount of silicon powder, sodium fluoride powder, sodium fluorosilicate powder, alumina powder and yttrium oxide powder in proportion, mix them evenly, and obtain the infiltration agent powder. The molybdenum alloy ingots were cut and sampled, then ground, polished, cleaned and dried. The infiltration agent powder is filled into an alumina crucible, and then the dried molybdenum alloy ingot is completely embedded in the infiltration agent powder, ensuring that the molybdenum alloy ingot substrate has no direct contact with the inner wall of the crucible. After that, the crucible is covered with the matching end cap and sealed. Then, the sealed crucible is transferred into the tube furnace cavity. In an inert atmosphere with argon as the protective gas, silicon infiltration is performed according to the preset silicon infiltration process parameters. After the silicon infiltration process is completed, the argon protective atmosphere is kept unchanged, and the crucible is allowed to cool naturally to room temperature with the tube furnace, finally obtaining a molybdenum alloy with an in-situ composite coating on the surface.
[0013] As a preferred embodiment of the present invention, the pressing is carried out by cold isostatic pressing followed by hot pressing and sintering.
[0014] As a preferred embodiment of the present invention, the infiltrator powder is prepared by ball milling and mixing the following raw materials in the indicated mass fractions: 10-25% silicon powder, 2-7% sodium fluoride powder, 2-5% sodium fluorosilicate powder, 1-6% yttrium oxide powder, and the balance being alumina powder.
[0015] As a preferred embodiment of the present invention, the sealing is performed using a slurry prepared from Al2O3 powder and high-temperature silica sol.
[0016] As a preferred embodiment of the present invention, the silicon infiltration treatment specifically involves maintaining the temperature at 1050℃~1200℃ for 6~15h.
[0017] The present invention has at least the following beneficial effects: (1) The present invention uses a matrix alloying method to prepare a molybdenum alloy, which itself has excellent high-temperature oxidation resistance. Specifically, under high-temperature oxidation conditions, a dense oxide film with self-healing ability can be generated on the surface of the molybdenum alloy. This oxide film can effectively block oxygen from diffusing into the matrix, thereby forming a reliable protection for the alloy matrix. At the same time, the alloy can stably meet the application requirements of high temperature, short service time and high reliability, and is suitable for use under extreme conditions.
[0018] (2) This invention uses a combination of matrix alloying and surface modification, and a method combining alloying and multilayer structure modification of silicide coatings to prepare RE m TaO n Molybdenum alloys protected by (Mo, Ta)Si2 and (Mo, Ta)5Si3 coatings have excellent high-temperature oxidation resistance and meet the requirements of high-temperature applications.
[0019] (3) This invention employs a synergistic technical solution combining substrate alloying and surface composite coating preparation. By controlling the properties of the substrate through substrate alloying and simultaneously constructing a composite coating on its surface, the difference in thermal expansion coefficients between the coating and the substrate can be effectively reduced, thereby forming a dense and firmly bonded protective coating, significantly improving the coating's thermal shock resistance. Specifically, this invention prepares RE on the surface of molybdenum alloy using an embedding infiltration method. m TaO n The composite coatings of (Mo, Ta)Si2 and (Mo, Ta)5Si3 exhibit uniform composition, dense structure, and tight adhesion to the molybdenum alloy substrate. During high-temperature oxidation, this coating system promotes the formation of a highly viscous SiO2 protective film on the alloy surface. The high viscosity of this protective film effectively enhances the material's erosion resistance, ensuring the service stability of the molybdenum alloy under extreme conditions.
[0020] (4) This invention has the core advantages of simple process, convenient operation, high yield and excellent preparation efficiency. It can be stably applied to extreme high temperature environment of 2000℃. It not only meets the needs of industrial mass production, but also has important practical value for the preparation of high temperature hot end components in key fields such as aerospace, nuclear industry and metallurgical industry. It has broad application prospects. Attached Figure Description
[0021] Figure 1 This is a cross-sectional view of the protective oxide layer formed on the surface of the molybdenum alloy substrate prepared in Example 1 of the present invention after oxidation at 2000℃ for 2.5 min; Figure 2 This is a cross-sectional view of the protective oxide layer formed on the surface of the molybdenum alloy substrate prepared in Example 2 of the present invention after oxidation at 2000℃ for 2.5 min; Figure 3 This is a cross-sectional microstructure image of the molybdenum alloy with an antioxidant coating prepared in Example 3 of the present invention; Figure 4 This is a cross-sectional microstructure image of the molybdenum alloy with an antioxidant coating prepared in Example 4 of the present invention; Figure 5 This is a cross-sectional view of the coating of the molybdenum alloy with an antioxidant coating prepared in Example 4 of the present invention after oxidation at 2000℃ for 10 min. Detailed Implementation
[0022] The embodiments of the present invention are described in detail below. These embodiments are exemplary and are only used to explain the present invention, and should not be construed as limiting the invention. Where specific techniques or conditions are not specified in the embodiments, they are performed according to the techniques or conditions described in the literature in the art or according to the product instructions. Reagents or instruments used, unless otherwise specified, are all commercially available conventional products.
[0023] Example 1 Step 1, preparation of molybdenum alloy: Weigh the corresponding raw materials according to the ratio of 59wt%Mo, 32wt%Ta, and 9wt%RE, and prepare the molybdenum alloy by cold isostatic pressing followed by hot pressing sintering. The hot pressing sintering temperature is 1300℃, the pressure is 950MPa, the holding time is 90s, and the pressurization rate is 70MPa / s.
[0024] Step 2, Sample preparation: A 5×10×10mm sample was cut from the matrix obtained in Step 1 using wire cutting. The sample was then successively polished with 400#, 600#, 800#, 1000#, and 1200# silicon carbide sandpaper. After ultrasonic cleaning in anhydrous ethanol for 5 minutes, the sample was dried.
[0025] Step 3, Self-oxidation resistance test: The previously polished and dried substrate was subjected to a 2000℃, 2.5min oxy-acetylene flame high-temperature test (using a stable oxy-acetylene flame as the heat source, the flame was directed onto the sample at a 90° angle to ablate the material). During the experiment, the oxygen-acetylene mixing ratio was controlled between 1.25 and 1.30. After the experiment, the oxide film on the sample surface was dense and intact, with no peeling, and the sample weight gain was 0.001%. After oxidation, a dense oxide film was formed on the sample surface ( Figure 1 As shown in the figure, this indicates that the alloy exhibits excellent erosion resistance and superior high-temperature oxidation resistance.
[0026] Example 2 Step 1, Preparation of molybdenum alloy: Weigh the corresponding raw materials according to the ratio of 79.5wt%Mo, 16wt%Ta, and 4.5wt%RE, and prepare the molybdenum alloy by cold isostatic pressing followed by hot pressing sintering. The hot pressing sintering temperature is 1300℃, the pressure is 950MPa, the holding time is 90s, and the pressurization rate is 70MPa / s.
[0027] Step 2, Sample preparation: A 5×10×10mm sample was cut from the matrix obtained in Step 1 using wire cutting. The sample was then successively polished with 400#, 600#, 800#, 1000#, and 1200# silicon carbide sandpaper. After ultrasonic cleaning in anhydrous ethanol for 5 minutes, the sample was dried.
[0028] Step 3, Self-oxidation resistance test: The previously polished and dried substrate sample was subjected to a 2000℃, 2.5min oxy-acetylene flame high-temperature test (using a stable oxy-acetylene flame as the heat source, the flame was directed onto the sample at a 90° angle to ablate the material). During the test, the oxygen-acetylene mixing ratio was controlled between 1.25 and 1.30. After the test, the oxide film on the sample surface was dense and intact, with no peeling, and the sample weight gain was -0.302%. After oxidation, a dense oxide film was formed on the sample surface ( Figure 2 As shown in the figure, this indicates that the alloy exhibits excellent erosion resistance and superior high-temperature oxidation resistance.
[0029] Example 3 Step 1, preparation of molybdenum alloy: Weigh the corresponding raw materials according to the ratio of 59wt%Mo, 32wt%Ta, and 9wt%RE, and prepare the molybdenum alloy by cold isostatic pressing followed by hot pressing sintering. The hot pressing sintering temperature is 1300℃, the pressure is 950MPa, the holding time is 90s, and the pressurization rate is 70MPa / s.
[0030] Step 2, Sample preparation: A 5×10×10mm sample was cut from the matrix obtained in Step 1 using wire cutting. The sample was then successively polished with 400#, 600#, 800#, 1000#, and 1200# silicon carbide sandpaper. After ultrasonic cleaning in anhydrous ethanol for 5 minutes, the sample was dried.
[0031] Step 3, Coating Preparation: Silicon powder, sodium fluoride powder, sodium fluorosilicate powder, yttrium oxide powder, and alumina powder are mixed in a certain proportion and then ball-milled at 170 rpm for 6 hours using a planetary ball mill to obtain the infiltrator powder. The composition is: 24 wt% silicon powder, 3 wt% sodium fluoride powder, 4 wt% yttrium oxide powder, 3 wt% sodium fluorosilicate powder, and 66 wt% alumina powder. The purity of each component is not less than 99.0%.
[0032] After loading the infiltrating agent into an alumina crucible, the previously polished and dried substrate is embedded in the infiltrating agent powder. The crucible is then covered and sealed with a slurry made of Al2O3 powder and high-temperature silica sol in a mass ratio of 4:1. The sealed crucible is placed in a tube furnace and heated to 1100℃ under an argon atmosphere for 10 hours to complete the silicon infiltration process and obtain RE. m TaO n Antioxidant coatings of (Mo, Ta)Si2 and (Mo, Ta)5Si3; The microstructure of the coating section obtained in step three is shown below. Figure 3 The coating is dense and does not peel off.
[0033] Step 4, High-Temperature Testing: The siliconized matrix sample was subjected to a 2000℃, 10min oxy-acetylene flame high-temperature testing test (using a stable oxy-acetylene flame as the heat source, the flame was directed onto the sample at a 90° angle to ablate the material). During the test, the oxygen-acetylene mixing ratio was controlled between 1.25 and 1.30. After the test, the oxide film on the sample surface was dense and intact, with no peeling, and the sample weight gain was -0.162%. The formation of a dense oxide film on the sample surface after oxidation indicates that the alloy exhibits excellent erosion resistance and excellent high-temperature oxidation resistance.
[0034] Example 4 Step 1, Preparation of molybdenum alloy: Weigh the corresponding raw materials according to the ratio of 79.5wt%Mo, 16wt%Ta, and 4.5wt%RE, and prepare the molybdenum alloy by cold isostatic pressing followed by hot pressing sintering. The hot pressing sintering temperature is 1300℃, the pressure is 950MPa, the holding time is 90s, and the pressurization rate is 70MPa / s.
[0035] Step 2, Sample preparation: A 5×10×10mm sample was cut from the matrix obtained in Step 1 using wire cutting. The sample was then successively polished with 400#, 600#, 800#, 1000#, and 1200# silicon carbide sandpaper. After ultrasonic cleaning in anhydrous ethanol for 5 minutes, the sample was dried.
[0036] Step 3, Coating Preparation: Silicon powder, sodium fluoride powder, sodium fluorosilicate powder, yttrium oxide powder, and alumina powder are mixed in a certain proportion and then ball-milled at 170 rpm for 6 hours using a planetary ball mill to obtain the infiltrator powder. The composition is: 24 wt% silicon powder, 3 wt% sodium fluoride powder, 4 wt% yttrium oxide powder, 3 wt% sodium fluorosilicate powder, and 66 wt% alumina powder. The purity of each component is not less than 99.0%.
[0037] After loading the infiltrating agent into an alumina crucible, the previously polished and dried substrate is embedded in the infiltrating agent powder. The crucible is then covered and sealed with a slurry made of Al2O3 powder and high-temperature silica sol in a mass ratio of 4:1. The sealed crucible is placed in a tube furnace and heated to 1100℃ under an argon atmosphere for 10 hours to complete the silicon infiltration process and obtain RE. m TaO n Antioxidant coatings of (Mo, Ta)Si2 and (Mo, Ta)5Si3; The microstructure of the coating section obtained in step three is shown below. Figure 4 The coating is dense and does not peel off.
[0038] Step 4, High-Temperature Testing: The aforementioned siliconized substrate sample underwent a 2000℃, 10min oxy-acetylene flame high-temperature testing experiment (using a stable oxy-acetylene flame as the heat source, the flame was directed onto the sample at a 90° angle to ablate the material). During the experiment, the oxygen-acetylene mixing ratio was controlled between 1.25 and 1.30. After the experiment, the oxide film on the sample surface was dense and intact, with no peeling, and the sample weight gain was -0.145%. After oxidation, a dense oxide film was formed on the sample surface (e.g., ...). Figure 5 As shown in the figure, this indicates that the alloy exhibits excellent erosion resistance and superior high-temperature oxidation resistance.
[0039] Examples 1-4, after undergoing high-temperature oxidation testing at 2000℃, showed a dense and intact oxide film on the sample surface without peeling. In contrast, pure molybdenum and conventional molybdenum alloys exhibited extremely poor oxidation resistance under the same 2000℃ oxidation test conditions, easily experiencing severe high-temperature oxidation failure and thus lacking practical application value. Examples 1 and 2, being molybdenum alloys prepared by matrix alloying, stably meet the application requirements of high temperature, short-term service, and high reliability, adapting to the needs of extreme operating conditions. Examples 3 and 4 showed significantly extended high-temperature oxidation resistance time, demonstrating superior high-temperature oxidation resistance.
[0040] The embodiments described above are merely preferred embodiments of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various other corresponding changes and modifications based on the technical solutions and concepts described above, and all such changes and modifications should fall within the protection scope of the claims of the present invention.
Claims
1. A high-temperature, high-strength, antioxidant molybdenum alloy with an in-situ self-healing antioxidant film, characterized in that, include: The molybdenum alloy matrix comprises the following components: 10-25 wt% Ta, 3.0-10 wt% rare earth elements, and the balance being Mo.
2. The high-temperature, high-strength, oxidation-resistant molybdenum alloy with an in-situ self-healing antioxidant film as described in claim 1, characterized in that, It also includes an antioxidant coating formed on the surface of the molybdenum alloy substrate, the antioxidant coating containing at least RE m TaO n phase, (MO, Ta)Si2 phase and (MO, Ta)5Si3 phase.
3. The high-temperature, high-strength, antioxidant molybdenum alloy with an in-situ self-healing antioxidant film as described in claim 2, characterized in that, The antioxidant coating has at least a two-layer structure, with the outer layer having at least RE. m TaO n The inner layer contains at least one (Mo, Ta)Si2 phase and at least one (Mo, Ta)5Si3 phase.
4. The high-temperature, high-strength, antioxidant molybdenum alloy with an in-situ self-healing antioxidant film as described in claim 2, characterized in that, The thickness of the antioxidant coating is 110-130 μm.
5. A method for preparing a high-temperature, high-strength, antioxidant molybdenum alloy with an in-situ self-healing antioxidant film, characterized in that, Mo, Ta, and rare earth elements are mixed in proportion, pressed, and sintered to obtain molybdenum alloy ingots.
6. The method for preparing a high-temperature, high-strength molybdenum oxide alloy with an in-situ self-healing antioxidant film according to claim 5, characterized in that, It also includes the following steps: Weigh out a certain amount of silicon powder, sodium fluoride powder, sodium fluorosilicate powder, alumina powder and yttrium oxide powder in proportion, mix them evenly, and obtain the infiltration agent powder. The molybdenum alloy ingots were cut and sampled, then ground, polished, cleaned and dried. The infiltration agent powder is filled into an alumina crucible, and then the dried molybdenum alloy ingot is completely embedded in the infiltration agent powder, ensuring that the molybdenum alloy ingot substrate has no direct contact with the inner wall of the crucible. After that, the crucible is covered with the matching end cap and sealed. Then, the sealed crucible is transferred into the tube furnace cavity. In an inert atmosphere with argon as the protective gas, silicon infiltration is performed according to the preset silicon infiltration process parameters. After the silicon infiltration process is completed, the argon protective atmosphere is kept unchanged, and the crucible is allowed to cool naturally to room temperature with the tube furnace, finally obtaining a molybdenum alloy with an in-situ composite coating on the surface.
7. The method for preparing a high-temperature, high-strength, antioxidant molybdenum alloy with an in-situ self-healing antioxidant film according to claim 6, characterized in that, The pressing process employs a method of cold isostatic pressing followed by hot pressing and sintering.
8. The method for preparing a high-temperature, high-strength, antioxidant molybdenum alloy with an in-situ self-healing antioxidant film according to claim 6, characterized in that, The infiltrator powder is prepared by ball milling and mixing the following raw materials in the indicated mass fractions: 10-25% silicon powder, 2-7% sodium fluoride powder, 2-5% sodium fluorosilicate powder, 1-6% yttrium oxide powder, and the remainder being alumina powder.
9. The method for preparing a high-temperature, high-strength, antioxidant molybdenum alloy with an in-situ self-healing antioxidant film according to claim 6, characterized in that, In step four, the sealing is performed using a slurry prepared from Al2O3 powder and high-temperature silica sol.
10. The method for preparing a high-temperature, high-strength, antioxidant molybdenum alloy with an in-situ self-healing antioxidant film according to claim 6, characterized in that, In step four, the silicon infiltration process specifically involves holding the furnace at 1050℃~1200℃ for 6~15 hours, followed by furnace cooling.