Preparation method of Y2O3-Ta metal ceramic composite coating on tantalum alloy surface
The Y2O3-Ta cermet composite slurry is prepared by combining ball milling with ultrasonic dispersion, which solves the problems of complex preparation and high cost in the prior art, and achieves uniform and stable coating preparation, which is suitable for tantalum alloy surfaces, with good performance and cost advantages.
Patent Information
- Application Number
- CN202510895817.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-30
- Publication Date
- 2025-08-26
AI Technical Summary
In the prior art, the method of preparing Y2O3-Ta cermet composite slurry is complex and costly, and the uniformity and stability of the obtained slurry are poor, which affects the performance of subsequent molding and sintered products. The Y2O3-Ta coating is prone to cracking and failure.
The Y2O3-Ta cermet composite slurry is prepared by combining ball milling with ultrasonic dispersion. By selecting common industrial raw materials and adding dispersants, defoaming agents, adhesives and leveling agents, the preparation process is simplified, the uniformity and stability of the slurry are improved, and the coating is prevented from cracking.
It has achieved the preparation of Y2O3-Ta cermet composite coating with simple process and low cost. It has good coating uniformity and stability, high bonding strength, excellent thermal shock resistance and corrosion resistance, and is suitable for a variety of application scenarios.
Smart Images
Figure CN120533103A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of metal material surface treatment, and in particular to a method for preparing a Y2O3-Ta metal ceramic composite coating on the surface of a tantalum alloy. Background Art
[0002] Tantalum has excellent properties such as high melting point (3017℃), excellent corrosion resistance, good conductivity and ductility, and is widely used in electronics, chemical industry, aerospace and other fields.
[0003] However, tantalum has a weak resistance to oxidation in high-temperature, high-oxygen environments. Although an oxide film forms on its surface, this film is unstable and easily damaged under high-temperature, high-oxygen conditions, which in turn triggers further oxidation of the tantalum. This not only changes the surface properties of the tantalum but also erodes its internal structure, causing its performance to degrade. For example, in electronic devices, tantalum oxidation may affect its capacitance performance and stability; in chemical equipment, oxidation reduces tantalum's corrosion resistance and shortens the equipment's service life; and in the aerospace field, tantalum oxidation threatens the safe operation of aircraft. Therefore, to ensure that tantalum and its alloys can operate stably in high-temperature, high-oxygen environments and extend their service life, an anti-oxidation coating is usually applied to the surface of tantalum and its alloys.
[0004] Cermets combine the advantages of metals and ceramics, and have excellent properties such as high strength, high hardness, high temperature resistance, wear resistance and corrosion resistance. They have broad application prospects in aerospace, mechanical manufacturing, electronics and other fields.
[0005] Y2O3 has excellent high-temperature and chemical stability, while Ta metal has advantages such as a high melting point, high hardness, and good electrical conductivity. If Y2O3 and Ta are combined to form a metal-ceramic material, it is expected that a material with even better performance will be obtained.
[0006] However, the current method for preparing Y2O3-Ta metal-ceramic composite slurry has the disadvantages of complex preparation process and high cost. The uniformity and stability of the obtained slurry are poor, which affects the performance of subsequent molding and sintering products. In addition, the Y2O3-Ta coating is prone to cracking and failure due to the large difference in thermal properties.
[0007] Therefore, it is of great significance to develop a preparation method with simple preparation process, low cost, and the ability to obtain uniform and stable Y2O3-Ta metal-ceramic composite coating. Summary of the Invention
[0008] The technical problem to be solved by the present invention is to provide a method for preparing a Y2O3-Ta metal ceramic composite coating on a tantalum alloy surface with simple process, low cost and uniformity and stability.
[0009] To solve the above technical problems, the present invention provides a method for preparing a Y2O3-Ta metal-ceramic composite coating on a tantalum alloy surface, comprising the following steps: The Y2O3-Ta metal ceramic composite slurry is prepared by ball milling and ultrasonic dispersion using 8% to 20% of tantalum powder, 4% to 10% of niobium powder, 8% to 24% of yttrium oxide powder, 1.4% to 1.8% of silicon powder, 0.6% to 1% of molybdenum powder, 1.4% to 1.8% of zirconium powder, 52% to 58% of anhydrous ethanol, 4% of deionized water, 0.08% to 0.16% of dispersant, 0.08% to 0.16% of defoaming agent, 0.08% to 0.16% of adhesive, and 0.08% to 0.16% of leveling agent, in percentage by weight. The prepared Y2O3-Ta metal ceramic composite slurry is coated on a tantalum alloy substrate and then dried; After drying, the Y2O3-Ta metal ceramic composite coating is formed on the surface of the tantalum alloy substrate by high temperature sintering in a protective atmosphere. Furthermore, the preparation of the Y2O3-Ta metal ceramic composite slurry includes the following steps: Drying the yttrium oxide powder, tantalum powder, niobium powder, molybdenum powder, zirconium powder, and silicon powder respectively; The dried yttrium oxide powder, tantalum powder, niobium powder, molybdenum powder, zirconium powder, and silicon powder are mixed with anhydrous ethanol and ball-milled to obtain a first solution; Stirring and mixing the adhesive, leveling agent and deionized water to obtain a second solution; The first solution and the second solution are mixed, and then the dispersant is added thereto and stirred to obtain a third solution; Add the defoaming agent to the third solution, stir, and then ball mill to obtain a mixed slurry; The mixed slurry is ultrasonically dispersed in an ultrasonic dispersing device to obtain a Y2O3-Ta metal ceramic composite slurry.
[0010] Furthermore, the tantalum powder is a nearly spherical powder with a particle size of 1 to 3 μm, the niobium powder is a nearly spherical powder with a particle size of 1 to 3 μm, the yttrium oxide powder is an electro-fused yttrium oxide powder with a particle size of 500 nm to 1 μm, the molybdenum powder has a particle size of 1 to 3 μm, the zirconium powder has a particle size of 1 to 3 μm, and the silicon powder has a particle size of 5 to 15 μm.
[0011] Furthermore, the drying treatment of the yttrium oxide powder, tantalum powder, niobium powder, molybdenum powder, zirconium powder and silicon powder is to dry the yttrium oxide powder, tantalum powder, niobium powder, molybdenum powder, zirconium powder and silicon powder in a vacuum drying oven at a temperature of 50 to 80° C. for 2 to 4 hours.
[0012] Furthermore, when the dried yttrium oxide powder, tantalum powder, niobium powder, molybdenum powder, zirconium powder, and silicon powder are mixed with anhydrous ethanol and ball milled, the ball milling is carried out in a ball milling jar filled with argon gas, the ball milling medium is zirconia balls, the ball-to-material ratio is 3:1 to 5:1, the ball milling speed is 200 to 300 r / min, and the ball milling time is 12 to 24 hours.
[0013] Furthermore, the stirring is carried out in a magnetic stirrer, and the stirring time is 2 to 6 hours.
[0014] Furthermore, the dispersant is polyethylene glycol, the defoaming agent is isooctyl alcohol or n-butanol, the adhesive is polyethylene or polypropylene, and the leveling agent is polydimethylsiloxane.
[0015] Furthermore, the mixed slurry is ultrasonically dispersed in an ultrasonic dispersion device at a dispersing power of 200 to 400 W and a dispersing time of 30 to 60 min.
[0016] Furthermore, the step of drying the Y2O3-Ta metal ceramic composite slurry after coating it on the tantalum alloy substrate comprises: Drying the Y2O3-Ta metal ceramic composite slurry coated on the tantalum alloy substrate in the shade; The Y2O3-Ta metal ceramic composite slurry coated on the tantalum alloy substrate is dried in the shade and then dried at a temperature of 50 to 70° C. for 12 to 48 hours.
[0017] Furthermore, the step of high temperature sintering under a protective atmosphere includes: The Y2O3-Ta metal ceramic composite slurry coated on the tantalum alloy substrate is dried and then sintered at a high temperature of 1500-1700°C for 3-6 hours, with the protective atmosphere being argon.
[0018] The present invention provides a method for preparing a Y2O3-Ta metal ceramic composite coating on a tantalum alloy surface. The selected raw materials, such as yttrium oxide powder, tantalum powder, niobium powder, molybdenum powder, zirconium powder, and silicon powder, are all common industrial raw materials with relatively low prices. In addition, no special complex conditions such as high temperature and high pressure are required during the preparation process, which can reduce production costs.
[0019] In addition, the present invention provides a method for preparing a Y2O3-Ta metal ceramic composite coating on a tantalum alloy surface. When preparing a Y2O3-Ta metal ceramic composite slurry coated on the tantalum alloy surface, the mixture is subjected to ball milling and ultrasonic dispersion treatment, so that yttrium oxide powder and tantalum powder can be evenly dispersed in the slurry, thereby simplifying the preparation process and reducing equipment investment and operating steps.
[0020] At the same time, the present invention provides a method for preparing a Y2O3-Ta metal ceramic composite coating on a tantalum alloy surface. Adding a dispersant and a binder to the slurry can further improve the stability of the slurry, so that the obtained slurry has good fluidity and uniformity, which is beneficial to the subsequent coating, molding and sintering process of the slurry, and is beneficial to the preparation of a Y2O3-Ta metal ceramic composite coating with excellent performance. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 A flow chart of a method for preparing a Y2O3-Ta metal-ceramic composite coating on a tantalum alloy surface provided by the present invention is provided in an embodiment of the present invention; Figure 2 This is a SEM image of the coating surface magnified 500 times, obtained by the method for preparing a Y2O3-Ta metal-ceramic composite coating on a tantalum alloy surface provided in Example 2 of the present invention; Figure 3 This is a SEM image of the coating surface magnified 500 times, prepared by a method for preparing a Y2O3-Ta metal ceramic composite coating on a tantalum alloy surface provided as a comparative example of the present invention. DETAILED DESCRIPTION
[0022] See also Figure 1 The present invention provides a method for preparing a Y2O3-Ta metal ceramic composite coating on a tantalum alloy surface, comprising the following steps: Step 1) In terms of weight percentage, 8% to 20% tantalum powder; 4% to 10% niobium powder; 8% to 24% yttrium oxide powder; 1.4% to 1.8% silicon powder; 0.6% to 1% molybdenum powder; 1.4% to 1.8% zirconium powder; 52% to 58% anhydrous ethanol; 4% deionized water; 0.08% to 0.16% dispersant; 0.08% to 0.16% defoaming agent; 0.08% to 0.16% adhesive; and 0.08% to 0.16% leveling agent are used to prepare a Y2O3-Ta metal ceramic composite slurry by ball milling and ultrasonic dispersion.
[0023] The preparation of Y2O3-Ta metal ceramic composite slurry includes the following steps: 1) Drying the yttrium oxide powder, tantalum powder, niobium powder, molybdenum powder, zirconium powder, and silicon powder separately.
[0024] Among them, when drying yttrium oxide powder, tantalum powder, niobium powder, molybdenum powder, zirconium powder and silicon powder, the yttrium oxide powder, tantalum powder, niobium powder, molybdenum powder, zirconium powder and silicon powder are placed in a vacuum drying oven respectively, and then dried at a temperature of 50 to 80°C for 2 to 4 hours to remove moisture and impurities adsorbed on the surface of each powder.
[0025] Among them, the tantalum powder is a nearly spherical powder with a particle size of 1 to 3 μm, the niobium powder is a nearly spherical powder with a particle size of 1 to 3 μm, the yttrium oxide powder is an electric-fused yttrium oxide powder with a particle size of 500 nm to 1 μm, the molybdenum powder has a particle size of 1 to 3 μm, the zirconium powder has a particle size of 1 to 3 μm, and the silicon powder has a particle size of 5 to 15 μm.
[0026] 2) The dried yttrium oxide powder, tantalum powder, niobium powder, molybdenum powder, zirconium powder, and silicon powder are mixed with anhydrous ethanol and ball-milled to obtain a first solution.
[0027] In order to provide a mixing effect of various powders, dried yttrium oxide powder, tantalum powder, niobium powder, molybdenum powder, zirconium powder, and silicon powder are mixed with anhydrous ethanol and then placed on a planetary ball mill for ball milling.
[0028] In addition, in order to prevent the metal powder in the mixture from being oxidized during the ball milling process, argon is filled into the ball mill as a protective gas to isolate the mixture from the air and prevent the metal powder from reacting with oxygen and being oxidized.
[0029] Specifically, in order to achieve the desired ball milling mixing effect, during ball milling, the ball milling medium is zirconia balls, the ball-to-material ratio is 3:1 to 5:1, the ball milling speed is 200 to 300 r / min, and the ball milling time is 12 to 24 hours.
[0030] 3) The adhesive, leveling agent and deionized water are stirred and mixed to obtain a second solution.
[0031] When the adhesive, the leveling agent and the deionized water are mixed and stirred, the adhesive, the leveling agent and the deionized water are stirred in a magnetic stirrer to be uniformly mixed.
[0032] The adhesive is polyethylene or polypropylene, and the leveling agent is polydimethylsiloxane. The added adhesive enhances the adhesion between the slurry and the substrate when the slurry is subsequently applied or sprayed onto the substrate, allowing the slurry to adhere firmly to the substrate surface. The added leveling agent promotes smoothness and evenness of the coating, helping to achieve a uniform, high-quality coating.
[0033] 4) The first solution and the second solution are mixed, and then the dispersant is added and stirred to obtain a third solution.
[0034] After the first and second solutions are mixed, a dispersant is added and then stirred uniformly for 2 to 6 hours to obtain a third solution. If the solution volume is large, the stirring time needs to be extended to ensure uniform mixing of the solutes in the solution.
[0035] The dispersant is polyethylene glycol, which can effectively alleviate the agglomeration problem of ultrafine metal powder and ceramic powder, keep the mixed powder in a well-dispersed state in the solution system, greatly reduce the powder sedimentation rate, and ensure the uniformity and stability of the slurry.
[0036] 5) Add the defoaming agent to the third solution, stir, and then ball mill to obtain a mixed slurry.
[0037] After adding the defoaming agent to the third solution, the mixture is uniformly stirred in a magnetic stirrer for 4 to 6 hours to obtain a mixture.
[0038] In order to uniformly mix the yttrium oxide powder and the tantalum powder in the mixture, the stirred mixture is further subjected to ball milling treatment.
[0039] In order to prevent the metal powder in the mixture from being oxidized during the ball milling process, argon is filled into the ball mill as a protective gas to isolate the mixture from the air and prevent the metal powder from reacting with oxygen and being oxidized.
[0040] In addition, in order to achieve the desired ball milling mixing effect, during ball milling, the ball milling medium is zirconia balls, the ball-to-material ratio is 3:1 to 5:1, the ball milling speed is 200 to 300 r / min, and the ball milling time is 12 to 24 hours.
[0041] The defoaming agent is isooctyl alcohol or n-butanol. The added defoaming agent can eliminate bubbles generated during the stirring and coating process of the slurry, preventing bubbles from remaining in the coating and affecting its performance and appearance.
[0042] 6) Ultrasonic dispersion of the mixed slurry in an ultrasonic dispersion device to obtain a Y2O3-Ta metal ceramic composite slurry.
[0043] The ultrasonic dispersion of the mixed slurry is carried out in an ultrasonic dispersion device with a power of 200 to 400 W and a time of 30 to 60 minutes.
[0044] The present invention simplifies the preparation process by combining ball milling and ultrasonic dispersion, reducing equipment investment and operating steps. Furthermore, after ball milling and ultrasonic dispersion, the Y2O3 powder and Ta powder can be evenly dispersed in the slurry, and the added dispersant and binder can further improve the stability of the slurry, giving the resulting slurry good fluidity and uniformity, which is beneficial for subsequent molding and sintering processes. Furthermore, the raw materials selected in the present invention are all common industrial raw materials with relatively low prices, and the preparation process does not require special complex conditions such as high temperature and high pressure, thereby reducing production costs.
[0045] Step 2) coating the prepared Y2O3-Ta metal ceramic composite slurry on a tantalum alloy substrate and then drying; Among them, when drying the Y2O3-Ta metal ceramic composite slurry coated on the tantalum alloy substrate, in order to prevent a large amount of water in the slurry from volatilizing rapidly during the subsequent drying process and causing the coating to easily fall off from the substrate, the Y2O3-Ta metal ceramic composite slurry coated on the tantalum alloy substrate is first fully dried in the shade, and most of the water in the Y2O3-Ta metal ceramic composite slurry coated on the tantalum alloy substrate is removed by shade drying.
[0046] Since some moisture still exists in the Y2O3-Ta metal ceramic composite slurry coated on the tantalum alloy substrate after it is dried in the shade, in order to prevent the coating from cracking due to rapid evaporation of moisture during the subsequent high-temperature sintering process, the coating is further dried at a temperature of 50-70°C for 12-48 hours after it is dried in the shade to ensure that all moisture or other volatile substances in the coating are volatilized.
[0047] Step 3) After the Y2O3-Ta metal ceramic composite slurry coated on the tantalum alloy substrate is dried, the coating on the tantalum alloy substrate is sintered at a high temperature under a protective atmosphere to form a Y2O3-Ta metal ceramic composite coating on the surface of the tantalum alloy substrate. The high temperature sintering is carried out at a high temperature of 1500 to 1700° C., and the sintering time is 3 to 6 hours.
[0048] The protective atmosphere is argon. When argon is used as a protective gas, it can prevent the metal elements in the coating from reacting with oxygen in the air at high temperatures during high-temperature sintering and being oxidized, thereby affecting the quality of the coating.
[0049] The present invention provides a method for preparing a Y2O3-Ta metal-ceramic composite coating on a tantalum alloy surface. By varying the ratio of metal powder to ceramic powder in the slurry, within the present invention's range, only subtle adjustments to the ratio are required to customize coatings with different compositions. This customized design can meet a variety of application needs, from industrial fields with special coating performance requirements to projects requiring specialized structures such as multi-layer gradient coatings or composite coatings. By adjusting the ratio of raw materials, the coating composition can be precisely controlled, resulting in coating products that meet the needs of different scenarios.
[0050] The following is a detailed description of the preparation method of a Y2O3-Ta metal ceramic composite coating on a tantalum alloy surface provided by the present invention through examples and comparative examples.
[0051] Example 1 A method for preparing a Y2O3-Ta metal ceramic composite coating on a tantalum alloy surface comprises the following steps: S1 Raw material preparation: prepare by weight 8% tantalum powder, 4% niobium powder, 8% yttrium oxide powder (electrofused yttrium oxide powder, particle size 500nm), 1.4% silicon powder, 0.6% molybdenum powder, 1.4% zirconium powder, 58% anhydrous ethanol, 4% deionized water, 0.08% dispersant, 0.08% defoaming agent, 0.08% adhesive, and 0.08% leveling agent.
[0052] Y2O3 powder, Ta powder, Nb powder, Mo powder, Zr powder and Si powder were placed in a vacuum drying oven respectively and dried at 80°C for 6 h to remove moisture and impurities adsorbed on the powder surface.
[0053] Preparation of Solution S2 A: Add the processed yttrium oxide powder, tantalum powder, niobium powder, silicon powder, molybdenum powder, and zirconium powder to a planetary ball mill with anhydrous ethanol. Zirconia balls are used as the milling medium, and the ball-to-material ratio is 3:1. To prevent oxidation of the metal powders during milling, argon gas is introduced into the mill. Mill at 200 rpm for 24 hours to form Solution A.
[0054] S3 Solution B preparation: Add adhesive, leveling agent and deionized water into a magnetic stirrer and stir evenly to form solution B.
[0055] S4 Preparation of Solution C: Mix Solution A and Solution B, add dispersant, and continue mixing in a magnetic stirrer to form Solution C.
[0056] S5 Slurry Formation: Add a defoamer to Solution C and stir for 4 hours. Then, transfer the ball-milled mixed slurry to an ultrasonic dispersion device and ultrasonically disperse it at 200 W for 30 minutes to obtain a Y2O3-Ta-Nb-SiO2-Mo-Zr metal ceramic composite slurry.
[0057] S6 coating: A tantalum alloy mold with a complex structure is selected as the substrate, and the prepared Y2O3-Ta metal ceramic composite slurry is evenly attached to the surface of the substrate by brushing.
[0058] S7 Drying: First, dry the mold coated with slurry in the shade, and then dry it at 60℃ for 12 hours.
[0059] S8 Sintering: The dried mold is placed in a sintering furnace and sintered at a high temperature of 1600° C. in an argon atmosphere for 3 hours, thereby forming a Y2O3-Ta metal ceramic composite coating on the surface of the tantalum alloy.
[0060] Example 2 A method for preparing a Y2O3-Ta metal ceramic composite coating on a tantalum alloy surface comprises the following steps: S1 Raw Material Preparation: Prepare, by weight, 14% tantalum powder, 7% niobium powder, 16% yttrium oxide powder (fused yttrium oxide powder, 750nm particle size), 1.6% silicon powder, 0.8% molybdenum powder, 1.6% zirconium powder, 55% anhydrous ethanol, 4% deionized water, 0.12% dispersant, 0.12% defoamer, 0.12% adhesive, and 0.12% leveling agent. Place all powders in a vacuum drying oven at 80°C and dry for 6 hours.
[0061] Preparation of S2 Solution A: The above raw materials and anhydrous ethanol were added to a planetary ball mill with zirconia balls as the milling medium and a ball-to-material ratio of 4:1. After filling with argon gas, the mixture was ball milled at a speed of 250 r / min for 30 h to form Solution A.
[0062] S3 Solution B preparation: The adhesive, leveling agent and deionized water were mixed uniformly in a magnetic stirrer to obtain Solution B.
[0063] S4 Preparation of Solution C: Mix Solution A and Solution B, add dispersant, and stir evenly in a magnetic stirrer to form Solution C.
[0064] S5 Slurry Formation: Add defoaming agent to Solution C and stir for 6 hours. Then transfer the slurry to an ultrasonic dispersion device and ultrasonically disperse it at a power of 300 W for 45 minutes to obtain a Y2O3-Ta-Nb-SiO2-Mo-Zr metal-ceramic composite slurry.
[0065] S6 coating: Select a tantalum alloy component with a narrow inner cavity as the substrate, and use the dipping method to evenly coat the slurry on the surface of the substrate.
[0066] S7 Drying: First dry in the shade, then dry at 60℃ for 30h.
[0067] S8 Sintering: The dried parts are placed in a sintering furnace and sintered at a high temperature of 1600°C in an argon atmosphere for 4.5 hours to obtain a Y2O3-Ta metal ceramic composite coating on the surface of the tantalum alloy.
[0068] The SEM image of the surface of the Y2O3-Ta metal ceramic composite coating prepared on the surface of the tantalum alloy in the embodiment of the present invention after magnification 500 times is as follows: Figure 2 shown.
[0069] Example 3 A method for preparing a Y2O3-Ta metal ceramic composite coating on a tantalum alloy surface comprises the following steps: S1 Raw Material Preparation: Prepare, by weight, 20% tantalum powder, 10% niobium powder, 24% yttrium oxide powder (fused yttrium oxide powder, 1 μm particle size), 1.8% silicon powder, 1% molybdenum powder, 1.8% zirconium powder, 52% anhydrous ethanol, 4% deionized water, 0.16% dispersant, 0.16% defoamer, 0.16% binder, and 0.16% leveling agent. Dry each powder in a vacuum oven at 80°C for 12 hours.
[0070] Preparation of S2 Solution A: The treated raw materials and anhydrous ethanol were added to a planetary ball mill with zirconia balls as the milling medium and a ball-to-material ratio of 5:1. Argon was filled in and the mixture was ball milled at a speed of 300 r / min for 36 h to obtain Solution A.
[0071] S3 Solution B preparation: Mix the adhesive, leveling agent and deionized water in a magnetic stirrer to form solution B.
[0072] S4 Preparation of Solution C: Mix Solution A and Solution B, add a dispersant, and stir evenly in a magnetic stirrer to obtain Solution C.
[0073] S5 Slurry Formation: Add a defoamer to Solution C and stir for 4 hours. Then transfer the slurry to an ultrasonic dispersion device and ultrasonically disperse it at a power of 400 W for 60 minutes to produce a Y2O3-Ta-Nb-SiO2-Mo-Zr metal ceramic composite slurry.
[0074] S6 coating: A conventionally shaped tantalum alloy plate is used as the substrate, and the slurry is adhered to the substrate surface by spraying.
[0075] S7 Drying: First dry in the shade, then dry at 60°C for 16 hours.
[0076] S8 Sintering: The dried plate is placed in a sintering furnace and sintered at a high temperature of 1600°C in an argon atmosphere for 6 hours, thereby preparing a Y2O3-Ta metal ceramic composite coating on the surface of the tantalum alloy.
[0077] Comparative Example 1 Coating preparation 1. Slurry Preparation: The slurry composition was the same as in Example 2, but the ultrasonic dispersion step was omitted. Solutions A, B, and C were prepared using the same method as in Example 2. A defoamer was added and stirred for 6 hours to obtain the slurry.
[0078] 2. Coating preparation: The coating, drying and sintering processes are consistent with those in Example 2.
[0079] The SEM image of the coating surface obtained in the comparative example of the present invention after magnification 500 times is as follows: Figure 3 shown.
[0080] First, through Figure 2 and Figure 3 It can be seen from the comparison that the coating prepared in Example 2 of the present invention is complete and uniform, while the coating prepared in Comparative Example 1, in which the slurry is not ultrasonically dispersed, has many fine cracks.
[0081] Then, other performance tests were performed on the Y2O3-Ta metal ceramic composite coatings prepared in Examples 1-3 of the present invention and the coating prepared in Comparative Example 1.
[0082] Appearance inspection: The surfaces of the coatings prepared in Examples 1-3 and Comparative Example 1 were observed with the naked eye and a microscope. It was found that the surfaces of the coatings prepared in Examples 1-3 were smooth and flat without obvious cracks, while the surface of the coating prepared in Comparative Example 1 had a small number of tiny cracks.
[0083] Bonding Strength Test: The bonding strength between the coating and the substrate was tested using a scratch test. The coatings in Examples 1-3 showed high bonding strength, with the coatings not easily falling off during the test. The coating in Comparative Example 1 showed relatively low bonding strength, with some coating falling off at the scratch.
[0084] Thermal shock resistance testing: Samples were heated to 1000°C in a high-temperature furnace, held at this temperature for 10 minutes, and then rapidly cooled in room-temperature water. This process was repeated 10 times. The coatings in Examples 1-3 showed no significant flaking or crack propagation; however, the coating in Comparative Example 1 exhibited some minor flaking.
[0085] Corrosion resistance test: After soaking the sample in a corrosive solution of a certain concentration for a certain period of time, the corrosion of the coating was observed. The coatings of Examples 1-3 were less corroded; the coating of Comparative Example 1 was more severely corroded, with more corrosion products on the surface.
[0086] By comparing the performance of the coatings prepared in Examples 1-3 of the present invention and Comparative Example 1, it can be seen that the Y2O3-Ta metal ceramic composite coatings prepared in Examples 1-3 of the present invention by combining ball milling with ultrasonic dispersion and adding suitable additives have good performance, simple preparation process, low cost, and have prospects for industrial application.
[0087] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.
Claims
1. A method for preparing a Y2O3-Ta metal ceramic composite coating on a tantalum alloy surface, characterized in that: The steps include: The Y2O3-Ta metal ceramic composite slurry is prepared by ball milling and ultrasonic dispersion using 8% to 20% of tantalum powder, 4% to 10% of niobium powder, 8% to 24% of yttrium oxide powder, 1.4% to 1.8% of silicon powder, 0.6% to 1% of molybdenum powder, 1.4% to 1.8% of zirconium powder, 52% to 58% of anhydrous ethanol, 4% of deionized water, 0.08% to 0.16% of dispersant, 0.08% to 0.16% of defoaming agent, 0.08% to 0.16% of adhesive, and 0.08% to 0.16% of leveling agent, in percentage by weight. The prepared Y2O3-Ta metal ceramic composite slurry is coated on a tantalum alloy substrate and then dried; After drying, the Y2O3-Ta metal ceramic composite coating is formed on the surface of the tantalum alloy substrate by high temperature sintering in a protective atmosphere.
2. The method for preparing a Y2O3-Ta metal ceramic composite coating on a tantalum alloy surface according to claim 1, characterized in that: The preparation of the Y2O3-Ta metal ceramic composite slurry comprises the following steps: Drying the yttrium oxide powder, tantalum powder, niobium powder, molybdenum powder, zirconium powder, and silicon powder respectively; The dried yttrium oxide powder, tantalum powder, niobium powder, molybdenum powder, zirconium powder, and silicon powder are mixed with anhydrous ethanol and ball-milled to obtain a first solution; Stirring and mixing the adhesive, leveling agent and deionized water to obtain a second solution; The first solution and the second solution are mixed, and then the dispersant is added thereto and stirred to obtain a third solution; Add the defoaming agent to the third solution, stir, and then ball mill to obtain a mixed slurry; The mixed slurry is ultrasonically dispersed in an ultrasonic dispersing device to obtain a Y2O3-Ta metal ceramic composite slurry.
3. The method for preparing a Y2O3-Ta metal ceramic composite coating on a tantalum alloy surface according to claim 2, characterized in that: The tantalum powder is a nearly spherical powder with a particle size of 1 to 3 μm, the niobium powder is a nearly spherical powder with a particle size of 1 to 3 μm, the yttrium oxide powder is an electro-fused yttrium oxide powder with a particle size of 500 nm to 1 μm, the molybdenum powder has a particle size of 1 to 3 μm, the zirconium powder has a particle size of 1 to 3 μm, and the silicon powder has a particle size of 5 to 15 μm.
4. The method for preparing a Y2O3-Ta metal ceramic composite coating on a tantalum alloy surface according to claim 3, characterized in that: The drying treatment of the yttrium oxide powder, tantalum powder, niobium powder, molybdenum powder, zirconium powder and silicon powder is to dry the yttrium oxide powder, tantalum powder, niobium powder, molybdenum powder, zirconium powder and silicon powder in a vacuum drying oven at a temperature of 50 to 80° C. for 2 to 4 hours.
5. The method for preparing a Y2O3-Ta metal ceramic composite coating on a tantalum alloy surface according to claim 4, characterized in that: When the dried yttrium oxide powder, tantalum powder, niobium powder, molybdenum powder, zirconium powder, and silicon powder are mixed with anhydrous ethanol and ball milled, the ball milling is carried out in a ball milling jar filled with argon gas, the ball milling medium is zirconia balls, the ball-to-material ratio is 3:1-5:1, the ball milling speed is 200-300 r / min, and the ball milling time is 12-24 hours.
6. The method for preparing a Y2O3-Ta metal ceramic composite coating on a tantalum alloy surface according to claim 5, characterized in that: The stirring is carried out in a magnetic stirrer for 2 to 6 hours.
7. The method for preparing a Y2O3-Ta metal ceramic composite coating on a tantalum alloy surface according to claim 6, characterized in that: The dispersant is polyethylene glycol, the defoaming agent is isooctyl alcohol or n-butanol, the adhesive is polyethylene or polypropylene, and the leveling agent is polydimethylsiloxane.
8. The method for preparing a Y2O3-Ta metal ceramic composite coating on a tantalum alloy surface according to claim 7, characterized in that: The mixed slurry is ultrasonically dispersed in an ultrasonic dispersion device at a dispersing power of 200 to 400 W and a dispersing time of 30 to 60 minutes.
9. The method for preparing a Y2O3-Ta metal ceramic composite coating on a tantalum alloy surface according to claim 1, characterized in that: The step of coating the Y2O3-Ta metal ceramic composite slurry on the tantalum alloy substrate and then drying the slurry comprises: Drying the Y2O3-Ta metal ceramic composite slurry coated on the tantalum alloy substrate in the shade; The Y2O3-Ta metal ceramic composite slurry coated on the tantalum alloy substrate is dried in the shade and then dried at a temperature of 50 to 70° C. for 12 to 48 hours.
10. The method for preparing a Y2O3-Ta metal ceramic composite coating on a tantalum alloy surface according to claim 1, characterized in that: The step of high temperature sintering under protective atmosphere comprises: The Y2O3-Ta metal ceramic composite slurry coated on the tantalum alloy substrate is dried and then sintered at a high temperature of 1500-1700°C for 3-6 hours, with the protective atmosphere being argon.