Tantalum alloy metal powder suitable for metal additive manufacturing and method of making the same

Abstract

The application discloses a tantalum alloy metal powder suitable for metal additive manufacturing and a preparation method thereof, and relates to the technical field of additive manufacturing. The application utilizes cationic surfactant to treat tantalum powder, utilizes anionic surfactant to treat active particles, and then utilizes electrostatic interaction between different positive and negative charges to synthesize self-assembled active composite powder. The prepared tantalum alloy spherical powder still maintains good sphericity, hardly causes influence on powder sphericity and fluidity, and can promote good metallurgical reaction between micro-nano particles and a matrix in an additive manufacturing part, so that the micro-nano particles can form various tantalum alloy high-performance materials required by users.

Description

Technical Field

[0001] This invention relates to the field of additive manufacturing technology, and more specifically, to tantalum alloy metal powder suitable for metal additive manufacturing and its preparation method. Background Technology

[0002] Tantalum alloys, as advanced metallic materials with excellent high-temperature performance, corrosion resistance, and good mechanical properties, are widely used in aerospace, nuclear energy, electronics manufacturing, chemical industry, and defense, playing an irreplaceable role, especially under extreme environments with high temperatures, corrosion, and mechanical loads. With the increasing demand for lightweight structures and integrated structural-functional designs, the research and development of tantalum alloy materials faces greater challenges. In particular, while reducing overall weight and improving comprehensive performance, it is necessary to develop technologies suitable for high-performance, lightweight tantalum alloys.

[0003] Traditional methods for preparing tantalum alloys, such as powder metallurgy and smelting, can yield materials with certain properties, but these methods often suffer from complex processes, high costs, and long lead times. Furthermore, the material's performance may not meet high standards for different applications. For example, some tantalum alloys improve their mechanical strength and corrosion resistance by adding refractory metal elements such as tungsten and niobium, and then optimize the alloy grain size through rolling to achieve large deformation followed by high-temperature treatment or other heat treatment processes. However, these processes are often complex and time-consuming, limiting the effectiveness of subsequent performance improvements. Taking the tantalum alloy patent with publication number CN116855807A as an example, this patent describes a process where tantalum powder and tungsten powder are vacuum-mixed in a specific ratio to obtain a composite powder. This composite powder is then sintered in a mold, cold-rolled, and finally annealed under vacuum heat treatment. The tantalum alloy prepared through this process has fine grains and good performance. Although this method has made some progress in certain fields, it still faces challenges such as high cost, long lead times, and complex post-processing.

[0004] In the research and development of tantalum alloys, traditional preparation methods typically require high-temperature treatment to ensure the high strength and hardness of the alloys. However, this process is complex, energy-intensive, and has a significant environmental impact. Therefore, to better address these issues, researchers have begun exploring the application of additive manufacturing technology in tantalum alloy materials. Additive manufacturing technology not only enables the rapid prototyping of complex structures but also improves the design flexibility and process controllability of tantalum alloys while maintaining their high strength and thermal conductivity. Related research shows that the additive manufacturing process of tantalum alloys, especially through laser 3D printing technology, can effectively avoid problems such as powder forming and cold welding in traditional methods, improve powder flowability and particle uniformity, and precisely control the microstructure of the alloy during the forming process, thereby enhancing the overall performance of tantalum alloys.

[0005] However, despite the enormous potential of additive manufacturing technology in the preparation of tantalum alloy materials, several challenges remain in practical applications. For example, the preparation process of tantalum alloy powders suffers from irregular powder shapes and high surface activity. These factors not only affect the powder's flowability and processability but may also lead to microscopic defects during the forming process, thereby impacting the mechanical properties and corrosion resistance of the finished product. Therefore, developing highly active, easily prepared, and highly spherical tantalum alloy powders suitable for additive manufacturing is a pressing technical challenge that needs to be overcome.

[0006] In view of this, the present invention is proposed. Summary of the Invention

[0007] The purpose of this invention is to provide tantalum alloy metal powder for metal additive manufacturing and its preparation method, aiming to provide tantalum alloy powder with high activity, easy preparation and high sphericity for additive manufacturing.

[0008] This invention is implemented as follows:

[0009] In a first aspect, the present invention provides a method for preparing tantalum alloy metal powder suitable for metal additive manufacturing, comprising:

[0010] Pure tantalum powder and a cationic surfactant solution were mixed and then separated to obtain modified tantalum powder;

[0011] The active particles and an anionic surfactant solution are mixed and separated to obtain modified active particles; wherein the material of the active particles is selected from at least one of Cu, Al, Si, Ti, Y, Mg, Zn and their oxides;

[0012] Modified tantalum powder and modified active particles were mixed and reacted in a reaction solvent, and then separated to obtain self-assembled active composite powder.

[0013] In an optional embodiment, during the preparation of the modified tantalum powder, the cationic surfactant in the cationic surfactant solution is selected from at least one of (3-aminopropyl)triethoxysilane, alkyltrimethylammonium chloride, alkylammonium chloride, and alkylmethylammonium chloride; preferably (3-aminopropyl)triethoxysilane;

[0014] The amount of tantalum powder used for 1L of cationic surfactant is 1g-50g, and 5g-30g is selected.

[0015] The particle size of the tantalum powder is 15μm-150μm, and is selected to be 15μm-53μm.

[0016] In an optional embodiment, the process of preparing modified tantalum powder includes: mixing and stirring tantalum powder and a cationic surfactant solution, followed by multiple filtrations and washings;

[0017] The dispersing solvent and the washing solvent of the cationic surfactant solution are both independently selected from at least one of aqueous ethanol, tetrahydrofuran, dimethylformamide, and diethyl ether.

[0018] In an optional embodiment, during the preparation of modified active particles, the anionic surfactant in the anionic surfactant solution is selected from at least one of sodium dodecyl sulfate, sodium dodecylbenzene sulfonate, polyacrylamide, and α-olefin sulfonic acid, and is selected as sodium dodecyl sulfate.

[0019] The mass ratio of anionic surfactant to active particles is 1:(0.3-2.0), and the concentration of anionic surfactant in the anionic surfactant solution is 0.5 g / L-1.5 g / L;

[0020] The particle size of the active particles is 50nm-500nm.

[0021] In an optional embodiment, the process of preparing modified active particles includes: washing the surface of the active particles with acid and then mixing and stirring them with an anionic surfactant solution, followed by filtration and washing.

[0022] The pickling solution used in the surface pickling process is selected from at least one of dilute hydrochloric acid and dilute nitric acid, and the mass fraction of the pickling solution is 0.1%-10%.

[0023] The dispersing solvent and the washing solvent of the anionic surfactant solution are both independently selected from at least one of tetrahydrofuran, dimethylformamide and diethyl ether.

[0024] In an optional embodiment, the process of preparing self-assembled active composite powder includes: mixing modified tantalum powder and a first reaction solvent to obtain a first mixture, mixing modified active particles and a second reaction solvent to obtain a second mixture, mixing and stirring the first mixture and the second mixture for 30 min-60 min, and then separating the solid and liquid components.

[0025] The mass ratio of modified active particles to modified tantalum powder is 1:(40-50);

[0026] The mixing and stirring method for the first and second mixtures is selected from at least one of vibration stirring and ultrasonic stirring;

[0027] The first reaction solvent is selected from at least one of aqueous ethanol, tetrahydrofuran, dimethylformamide, and diethyl ether; the second reaction solvent is selected from at least one of tetrahydrofuran, dimethylformamide, and diethyl ether.

[0028] Solid-liquid separation is performed using vacuum filtration, with the vacuum pressure controlled between 0.1 bar and 5.0 bar.

[0029] In an optional embodiment, the self-assembled active composite powder is freeze-dried to obtain tantalum alloy powder with nano-active powder uniformly loaded on the surface.

[0030] The freeze-drying temperature was controlled at -80℃ to -10℃, and the drying time was 2h to 10h. After that, the temperature was increased to room temperature at a rate of 1℃ / h to 50℃ / h.

[0031] In an optional embodiment, the method further includes drying the surface-treated powder;

[0032] The surface-treated powder is dried using vacuum drying, with the temperature controlled at 50℃-200℃ and the pressure at 0.1bar-5bar.

[0033] Secondly, the present invention provides a tantalum alloy metal powder suitable for metal additive manufacturing, which is prepared by any of the preparation methods described in the foregoing embodiments.

[0034] Thirdly, the present invention provides the application of the tantalum alloy metal powder of the foregoing embodiments in additive manufacturing;

[0035] The process of preparing tantalum alloy using tantalum alloy metal powder includes: setting the additive manufacturing processing path according to the established three-dimensional model, and using laser additive manufacturing technology to process and shape the target solid part.

[0036] The present invention has the following beneficial effects: The present invention uses cationic surfactants to treat tantalum powder and anionic surfactants to treat active particles. Then, it uses electrostatic interactions between different positive and negative charges to synthesize self-assembled active composite powders. The prepared tantalum alloy spherical powder still maintains good sphericity. It not only has almost no impact on the sphericity and flowability of the powder, but also promotes good metallurgical reaction between micro and nano particles and the matrix in additive manufacturing parts, so as to promote the formation of various high-performance tantalum alloy materials required by users. Attached Figure Description

[0037] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 Flowchart for the preparation of spherical powders for highly active metal additive manufacturing based on molecular self-assembly;

[0039] Figure 2The images shown are characterization diagrams of the Cu / Ta powder prepared in Example 1; (a) represents the SEM image, and (b) represents the EDS image.

[0040] Figure 3 Characterization images of the Cu / Ta powder prepared in Example 2; (a) shows the SEM image, and (b) shows the EDS image.

[0041] Figure 4 The images show the microstructures of the alloys prepared by SLM in Examples 1 and 3; (a) represents Example 1, and (b) represents Example 3.

[0042] Figure 5 The following are particle size distribution diagrams of the copper powder used in Examples 1 and 3; (a) represents the nano copper powder used in Example 1; (b) represents the micron copper powder used in Example 3;

[0043] Figure 6 Characterization images of the tantalum alloy metal powder prepared in Example 5; (a) shows the SEM image, and (b) and (c) show the EDS test images;

[0044] Figure 7 The microstructure of the nano-Y2O3 / Ta tantalum alloy composite material prepared by SLM in Example 5 is shown in (a) and (b) at different magnifications.

[0045] Figure 8 Characterization images of the tantalum alloy metal powder prepared in Example 6; (a) shows the SEM image, and (b) and (c) show the EDS test images;

[0046] Figure 9 The image shows the microstructure of the nano-TiO2 / Ta tantalum alloy composite material prepared by SLM in Example 6; (a) and (b) represent different magnifications. Detailed Implementation

[0047] To make the objectives, 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. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0048] Existing technologies for preparing tantalum alloy powder suffer from problems such as irregular powder shape and high surface activity. These factors not only affect the powder's flowability and processability but may also lead to microscopic defects during the forming process, thereby impacting the mechanical properties and corrosion resistance of the additively manufactured tantalum alloy powder products. Therefore, this invention improves the preparation process of tantalum alloy powder by utilizing the electrostatic interaction between different positive and negative charges to synthesize a novel powder.

[0049] This invention provides a method for preparing tantalum alloy metal powder suitable for metal additive manufacturing, such as... Figure 1 As shown, the steps are as follows:

[0050] S1. Preparation of modified tantalum powder

[0051] Tantalum powder (i.e., micron-sized spherical tantalum powder A) is mixed with a cationic surfactant solution. After thorough mixing and stirring to ensure uniform dispersion, modified tantalum powder is obtained by separation, resulting in a positively charged surface on the modified tantalum powder. The separation method is not limited and can include common methods such as filtration and washing. Multiple filtrations and washings can be performed to remove excess reaction products.

[0052] In some embodiments, the tantalum powder is spherical micron-sized tantalum powder A, with a particle size of 15μm-150μm, preferably 15μm-53μm, such as 15μm, 20μm, 30μm, 40μm, 53μm, 70μm, 100μm, 120μm, 150μm, etc. The purity of the tantalum powder can reach 99.00wt.%, purchased from Stardust Technology Co., Ltd.

[0053] In some embodiments, the cationic surfactant in the cationic surfactant solution is selected from at least one of (3-aminopropyl)triethoxysilane, alkyltrimethylammonium chloride, alkylammonium chloride, and alkylmethylammonium chloride. The cationic surfactant can be any one or more of these, and all of these cationic surfactants can effectively charge the surface of the tantalum powder. Comparing (3-aminopropyl)triethoxysilane and alkylmethylammonium chloride as cationic surfactants, (3-aminopropyl)triethoxysilane exhibits better self-assembly, resulting in better sphericity and superior mechanical properties of the tantalum alloy powder.

[0054] Furthermore, the amount of tantalum powder used corresponding to 1L of cationic surfactant is 1g-50g, such as 1g, 5g, 10g, 20g, 30g, 40g, 50g, etc. The specific amount of cationic surfactant is determined mainly by the dispersion effect of the powder in the reagent, such as whether there is obvious agglomeration or reaction. To improve the activation rate while ensuring uniform dispersion, the amount of tantalum powder used corresponding to 1L of cationic surfactant is 5g-30g.

[0055] In some embodiments, the dispersing solvent and the washing solvent of the cationic surfactant solution are both independently selected from at least one of aqueous ethanol, tetrahydrofuran, dimethylformamide, and diethyl ether, and are selected from at least one of aqueous ethanol, dimethylformamide, and diethyl ether.

[0056] S2. Preparation of modified active particles

[0057] The active particles (i.e., nano-sized active particles B) and the anionic surfactant solution are thoroughly mixed and stirred, and then separated to obtain modified active particles with negative surface charges. The separation method is not limited and can include common methods such as filtration or washing.

[0058] The active particles are selected from at least one of Cu, Al, Si, Ti, Y, Mg, Zn, and their oxides. The active particles can be any one or more of these materials, with a specific selection of Cu, Al, Zn, Si, and Ti. The appropriate active particles are chosen based on the material of the alloy product being prepared. The active particles are nanoscale, with a particle size of 50nm-500nm, such as 50nm, 100nm, 200nm, 300nm, 400nm, 500nm, etc. The purity of the active particles can be 99.00 wt.%, but is not limited to this.

[0059] In some embodiments, during the preparation of modified active particles, the anionic surfactant in the anionic surfactant solution is selected from at least one of sodium dodecyl sulfate, sodium dodecylbenzene sulfonate, polyacrylamide, and α-olefin sulfonic acid. The anionic surfactant can be any one or more of the above. Sodium dodecyl sulfate is selected as the anionic surfactant because it has a better self-assembly effect, resulting in better sphericity and flowability of the tantalum alloy powder.

[0060] Furthermore, the mass ratio of anionic surfactant to active particles is 1:(0.3-2.0), such as 1:0.3, 1:0.5, 1:1.0, 1:1.5, 1:2.0, etc.; the concentration of anionic surfactant in the solution is 0.5g / L-1.5g / L, such as 0.5g / L, 1.0g / L, 1.5g / L, etc. The amount of anionic surfactant is mainly adjusted based on the dispersion effect of the powder in the reagent, such as whether there is obvious agglomeration or reaction. Under the condition of uniform dispersion, in order to improve the activation rate, the amount of active particles corresponding to 1L of anionic surfactant is selected as 0.5g-2g.

[0061] In some embodiments, the process of preparing modified active particles includes: surface acid washing of the active particles followed by thorough mixing and stirring with an anionic surfactant solution, and then filtration and washing. Since the active particles are nanoscale, they are prone to agglomeration due to their electrostatic adsorption. Acid washing can eliminate this electrostatic adsorption, making them easier to disperse evenly before thorough mixing with the anionic surfactant.

[0062] Furthermore, the pickling solution used in the surface pickling process is a weak acid, selected from at least one of dilute hydrochloric acid and dilute nitric acid. Dilute hydrochloric acid is chosen because it can better disperse the nanoparticles. The mass fraction of the pickling solution is 0.1%-10%, such as 0.1%, 0.5%, 1.0%, 3.0%, 5.0%, 8.0%, 10.0%, etc.

[0063] In some embodiments, the dispersing solvent and the washing solvent of the anionic surfactant solution are both independently selected from at least one of tetrahydrofuran, dimethylformamide, and diethyl ether. The dispersing solvent and the washing solvent may be the same or different, and may be independently selected from any one or more of the above. The dispersing solvent and the washing solvent of the anionic surfactant solution are both independently selected from at least one of dimethylformamide and diethyl ether.

[0064] S3, Self-assembly

[0065] Modified tantalum powder and modified active particles are mixed and reacted in a reaction solvent, and then separated to obtain self-assembled active composite powder. Steps S1 and S2 effectively attach positive / negative charges to nanoparticles and micron-sized metal powders through surface modification, enabling the nanoparticles to be uniformly and quantitatively coated on the surface of micron-sized metal spheres in situ via Van der Waals forces, thus achieving personalized and customized preparation of tantalum alloy powder.

[0066] In some embodiments, the process of preparing self-assembled active composite powder includes: mixing modified tantalum powder and a first reaction solvent and allowing them to stand to obtain a first mixture; mixing modified active particles and a second reaction solvent and allowing them to stand to obtain a second mixture; mixing the first mixture and the second mixture; stirring the suspension for 30-60 minutes; and then separating the solid and liquid phases. The mass ratio of modified active particles to modified tantalum powder is 1:(40-50), and composite active tantalum alloy powder suitable for additive manufacturing can be prepared within this range.

[0067] Specifically, a second mixture containing nanoscale particles can be poured into a first mixture containing micron-scale particles. The mass ratio of modified active particles to modified tantalum powder can be 1:40, 1:43, 1:45, 1:48, 1:50, etc.

[0068] Furthermore, the mixing and stirring method for the first and second mixtures is selected from at least one of vibration stirring and ultrasonic stirring, with ultrasonic stirring being chosen to improve the uniformity of mixing. The first reaction solvent is selected from at least one of aqueous ethanol, tetrahydrofuran, dimethylformamide, and diethyl ether, and the first reaction solvent can be any one or more of the above; the second reaction solvent is selected from at least one of tetrahydrofuran, dimethylformamide, and diethyl ether, and the second reaction solvent can be any one or more of the above.

[0069] In some embodiments, solid-liquid separation can be performed by vacuum filtration, with the vacuum pressure controlled at 0.1 bar to 5.0 bar, such as 0.1 bar, 0.5 bar, 1.0 bar, 2.0 bar, 3.0 bar, 4.0 bar, 5.0 bar, etc., with a vacuum pressure of 0.5 bar to 2.0 bar being selected.

[0070] S4, freeze drying, vacuum drying

[0071] The self-assembled active composite powder is freeze-dried. In some embodiments, the freeze-drying temperature is controlled at -80℃ to -10℃ (selected as -50℃ to -20℃), the drying time is 2h to 10h (selected as 3h to 8h), and then the temperature is slowly increased to room temperature at a rate of 1℃ / h to 50℃ / h (selected as 5℃ / h to 20℃ / h), and then removed for later use. Specifically, the freeze-drying temperature can be -80℃, -70℃, -60℃, -50℃, -40℃, -30℃, -20℃, -10℃, etc.; the drying time can be 2h, 3h, 5h, 8h, 10h, etc.; and the heating rate can be 1℃ / h, 5℃ / h, 10℃ / h, 20℃ / h, 30℃ / h, 40℃ / h, 50℃ / h, etc.

[0072] Furthermore, the surface-treated powder is dried to further remove residual solvents. Vacuum drying can be used to dry the surface-treated powder, controlling the vacuum drying temperature to be 50℃-200℃ (selected as 80℃-120℃), such as 50℃, 80℃, 100℃, 130℃, 150℃, 180℃, 200℃, etc.; and the pressure to be 0.1bar-5bar (selected as 0.8bar-1.2bar), such as 0.1bar, 0.8bar, 1.0bar, 1.2bar, 1.0bar, 2.0bar, 3.0bar, 4.0bar, 5.0bar, etc.

[0073] This invention also provides a tantalum alloy metal powder suitable for metal additive manufacturing, which is prepared by the preparation method provided in this invention.

[0074] It should be noted that the preparation method provided in the embodiments of the present invention has the following advantages: (1) The tantalum alloy powder preparation method proposed in the present invention helps to reduce the problems of powder deformation and sphericity reduction caused by mechanical mixing of micro / nano particles / metal powder, and also avoids the phenomenon of nanoparticle agglomeration that is easy to occur when micro / nano particles / metal powder are mixed. The tantalum alloy spherical powder prepared by the present invention still maintains good sphericity, which not only has almost no impact on the sphericity and flowability of the powder, but also promotes the good metallurgical reaction between micro / nano particles and the matrix in SLM forming parts, and promotes the formation of various high-performance tantalum alloy materials required by users. (2) Since it can modify a layer of other highly active materials in situ and quantitatively on the surface of highly active tantalum alloy powder, it is an excellent method that can easily realize the ideas of material designers. (3) The method proposed in the present invention solves the problem that many highly active materials can only obtain the desired tantalum alloy powder through alloy proportioning, smelting, casting and a series of powder preparation processes.

[0075] The tantalum alloy metal powder provided in this invention can be used to prepare tantalum alloys via additive manufacturing. After preparing the powder using laser additive manufacturing technology, improvements in various mechanical properties of the SLM alloy are achieved, even surpassing the levels of cast materials with similar chemical compositions in some aspects. This indicates that it can be considered an excellent preparation method for obtaining special metal alloy powders for additive manufacturing, and also a good manufacturing method suitable for high-performance alloy materials.

[0076] In practice, the process of preparing tantalum alloy using tantalum alloy metal powder includes: setting the additive manufacturing processing path according to the established three-dimensional model, and using laser additive manufacturing technology to process and shape the target solid part.

[0077] Specifically, the 3D modeling software can be specialized modeling software such as UG, Solidworks, and CATIA. The scan path is created by converting information from the 3D model into multiple slices, defining each slice as a cross-sectional layer of the part, and then using the method described above to manufacture the solid.

[0078] Additively manufactured parts are produced through a series of additive manufacturing technologies, including: electron beam additive manufacturing (EBAM), direct metal deposition (DMD), direct metal laser sintering (DMLS), laser near-net-shape forming (LENS), laser metal forming (LMF), selective laser melting (SLM), selective laser sintering (SLS), and supersonic cold spraying (CS), among others. Selective laser melting (SLM) and laser near-net-shape forming (LENS) technologies are also selected.

[0079] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0080] Example 1

[0081] This embodiment provides a method for preparing tantalum alloy metal powder suitable for metal additive manufacturing. Irregular nano-pure Cu particles (99.9 wt.%) with an average particle size of 500 nm and spherical, atomized pure Ta powder with a particle size range of 15–53 μm are selected. Sodium dodecyl sulfate is selected as the anionic surfactant, and (3-aminopropyl)triethoxysilane is selected as the cationic surfactant. Then, according to… Figure 1 The preparation sequence of the spherical powder shown is as follows: 2 wt.% of nano-pure Cu particles are weighed, and 98 wt.% of pure Ta powder is surface-modified to produce composite powder. The specific operation steps are as follows:

[0082] (1) Surface modification of pure Ta powder using (3-aminopropyl)triethoxysilane: 50 g of pure Ta powder was added to 2 L of ethanol-water solution (1:1) and stirred for 10 minutes to ensure uniform dispersion. Then, 1 L of (3-aminopropyl)triethoxysilane solvent was added to the suspension. After thorough mixing at room temperature for 1 hour, amine-functionalized pure Ta powder was obtained, resulting in a positively charged powder surface. After filtering the product, it was washed three times with ethanol and deionized water to remove residual reactants. Subsequently, the (3-aminopropyl)triethoxysilane-modified pure Ta powder was redispersed in 3 L of deionized water. Finally, the suspension was treated with an ultrasonic device for 30 minutes.

[0083] (2) Dispersing nano-pure Cu particles using sodium dodecyl sulfate solvent: 1 gram of nano-pure Cu powder was washed three times with 0.1 wt% dilute hydrochloric acid, then added to 1 L of deionized water and mixed thoroughly. 1 g of sodium dodecyl sulfate powder was then added to prepare an anionic surfactant solution, which was ultrasonically stirred for 30 minutes. After filtration, the solution was washed three times with dimethylformamide to remove any remaining unreacted cationic surfactant.

[0084] (3) Surface modification of pure Ta powder with nano-pure Cu particles: The suspension of nano-pure Cu particles was slowly poured into the suspension of pure Ta powder. After stirring the above mixed suspension for 1 hour, the pure Ta powder modified with nano-pure Cu particles was collected by filtration under a vacuum pressure of 1 bar. The obtained product was placed in a drying oven and freeze-dried at -35°C for 5 hours, and then stored at room temperature (about 20-25°C).

[0085] The morphology and elemental distribution of the processed powder are as follows: Figure 2 As shown.

[0086] (4) Composite Powder Storage and Additive Manufacturing: The collected composite powder was placed in a vacuum drying oven with a vacuum pressure of approximately 120 MPa, heated to 120°C at a heating rate of 80°C / min, and held at this temperature for 2 hours before vacuum drying. The resulting alloy powder was then placed in a vacuum bag and stored under vacuum for later use. Subsequently, the nano-Cu / Ta alloy composite powder was poured into the powder storage chamber of the selective laser melting (SLM) additive manufacturing system and allowed to solidify using the laser.

[0087] The SLM process parameters in Example 1 are as follows: The alloy material is manufactured and its tribological properties are tested using an EOS M290 system. The specific process parameters are: laser spot size of 100 μm, laser power of 240 W, layer thickness of 20 μm, scanning spacing of 80 μm, and scanning speed of 660 mm / s.

[0088] It should be noted that the additive manufacturing system in step (5) can also be selected from any of the following technologies: electron beam additive manufacturing (EBAM), direct metal deposition (DMD), direct metal laser sintering (DMLS), laser near-net-shape forming (LENS), laser metal forming (LMF), selective laser melting (SLM), selective laser sintering (SLS), and supersonic cold spraying (CS). However, this invention selects selective laser melting (SLM) and laser near-net-shape forming (LENS) technologies.

[0089] Example 2

[0090] The only difference from Example 1 is that the cationic surfactant (3-aminopropyl)triethoxysilane is replaced with alkylmethylammonium chloride.

[0091] Example 3

[0092] The only difference from Example 1 is that the pure Cu particles are at the micrometer level, specifically with a particle size of 30 micrometers.

[0093] Example 4

[0094] The only difference from Example 2 is that the pure Cu particles are at the micrometer level, specifically with a particle size of 30 micrometers.

[0095] Example 5

[0096] This embodiment provides a micro / nano structured highly active spherical tantalum alloy, the preparation method of which differs from that of Example 1 in that 1g Cu is replaced with 1g Y2O3.

[0097] Example 6

[0098] This embodiment provides a micro / nano structured highly active spherical tantalum alloy, the preparation method of which differs from that of Example 1 in that 1g Cu is replaced with 1g TiO2.

[0099] Comparative Example 1

[0100] Micron-sized copper and tantalum mixed powder was prepared by planetary ball milling with the following parameters: ball-to-powder ratio 7:3, mixing time 8 h, and mixing speed 150 rpm.

[0101] The results showed that in Example 1, nano-copper and micron-sized tantalum powder mixed well, with the nano-copper adsorbing onto the surface of the pure tantalum powder. Tantalum-copper alloys were prepared using both micron-sized and nano-sized copper powders. In this case, the nano-copper powder was uniformly distributed, and the tantalum-copper microstructure was fine and the composition was uniformly distributed under SEM. However, in the comparative example, the tantalum-copper prepared using a mixture of micron-sized copper and tantalum powder prepared by planetary ball milling exhibited cracks, indicating that mechanical mixing methods present certain challenges in achieving homogenization of tantalum-copper.

[0102] In addition, the addition of Cu plays a role in solid solution strengthening. The Vickers hardness of pure tantalum and tantalum copper is shown in Table 1. The hardness of nano copper is increased by nearly 40 HV compared with pure tantalum, and the hardness of nano copper is increased by about 20 HV compared with micron copper, which significantly improves the performance.

[0103] Table 1. Average Hardness of Tantalum and Tantalum Alloys Prepared by SLM

[0104]

[0105] Figure 2 This refers to nano-Cu / Ta powder treated with (3-aminopropyl)triethoxysilane cationic surfactant. Figure 3 The image shows nano-Cu / Ta powder treated with an alkylmethylammonium chloride cationic surfactant. Figure 3 The results showed no detectable adhesion of nano-Cu particles to the small Ta powder, indicating that the self-assembly effect of the Ta powder treated with alkylmethylammonium chloride cationic surfactant was generally poor, and the powder was not mixed evenly, resulting in a decrease in microhardness.

[0106] Microstructure images of nano-Cu / Ta (Example 1) and micro-Cu / Ta (Example 3) prepared by SLM are shown below. Figure 4 As shown, it can be seen that the microstructure of Ta alloy is refined after using nano-Cu powder, while Ta-Cu alloy prepared using micron-sized Cu powder shows significant cracks. This may be due to the uneven mixing of micron-sized Ta and Cu powders, elemental separation during the preparation of the bulk, and the rapid solidification of Cu melt, where Ta may hinder its uniform shrinkage, forming microcracks at grain boundaries or around particles.

[0107] The copper powder particle size used in Examples 1 and 3 is as follows: Figure 5 As shown.

[0108] The characterization diagram of the tantalum alloy metal powder prepared in Example 5 is shown below. Figure 6 As shown, nano-scale Y₂O₃ is uniformly distributed on the Ta surface. The microstructure of the nano-Y₂O₃ / Ta tantalum alloy composite material prepared by SLM is as follows: Figure 7 .

[0109] SEM image of the tantalum alloy metal powder prepared in Example 6 is shown below. Figure 8 As shown, nano-sized Y₂O₃ is uniformly distributed on the Ta surface. The microstructure of the nano-TiO₂ / Ta tantalum alloy composite material prepared by SLM is as follows: Figure 9 .

[0110] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing tantalum alloy metal powder suitable for metal additive manufacturing, characterized in that, include: Tantalum powder and a cationic surfactant solution were mixed and then separated to obtain modified tantalum powder; The active particles and an anionic surfactant solution are mixed and separated to obtain modified active particles; wherein the material of the active particles is selected from at least one of Cu, Al, Si, Ti, Y, Mg, Zn and their oxides; The modified tantalum powder and the modified active particles are mixed and reacted in a reaction solvent, and then separated to obtain a self-assembled active composite powder. The self-assembled active composite powder is freeze-dried at a temperature of -80°C to -10°C for 2-10 hours, and then heated to room temperature at a rate of 1°C / h to 50°C / h. The mass ratio of the modified active particles to the modified tantalum powder is 1:(40-50). In the preparation of the modified tantalum powder, the cationic surfactant in the cationic surfactant solution is (3-aminopropyl)triethoxysilane; the amount of tantalum powder used per 1L of the cationic surfactant is 40g-50g; in the preparation of the modified active particles, the anionic surfactant in the anionic surfactant solution is sodium dodecyl sulfate; the mass ratio of the anionic surfactant to the active particles is 1:(0.3-2.0), and the concentration of the anionic surfactant in the anionic surfactant solution is 0.5g / L-1.5g / L; The tantalum powder has a particle size of 15μm-150μm, and the active particles have a particle size of 50nm-500nm.

2. The preparation method according to claim 1, characterized in that, The process of preparing the modified tantalum powder includes: mixing and stirring the tantalum powder and the cationic surfactant solution, followed by multiple filtrations and washings; The dispersing solvent and washing solvent of the cationic surfactant solution are both independently selected from at least one of aqueous ethanol, tetrahydrofuran, dimethylformamide, and diethyl ether.

3. The preparation method according to claim 1, characterized in that, The process of preparing the modified active particles includes: washing the surface of the active particles with acid and then mixing and stirring them with the anionic surfactant solution, followed by filtration and washing; The pickling solution used in the surface pickling process is selected from at least one of dilute hydrochloric acid and dilute nitric acid, and the mass fraction of the pickling solution is 0.1%-10%. The dispersing solvent and washing solvent of the anionic surfactant solution are both independently selected from at least one of tetrahydrofuran, dimethylformamide, and diethyl ether.

4. The preparation method according to claim 1, characterized in that, The process of preparing the self-assembled active composite powder includes: mixing modified tantalum powder and a first reaction solvent to obtain a first mixture, mixing the modified active particles and a second reaction solvent to obtain a second mixture, mixing and stirring the first mixture and the second mixture for 30 min-60 min, and then separating the solid and liquid components. The first mixture and the second mixture are mixed and stirred by vibration stirring; The first reaction solvent is selected from at least one of aqueous ethanol, tetrahydrofuran, dimethylformamide, and diethyl ether; the second reaction solvent is selected from at least one of tetrahydrofuran, dimethylformamide, and diethyl ether. Solid-liquid separation is performed using vacuum filtration, with the vacuum pressure controlled between 0.1 bar and 5.0 bar.

5. A tantalum alloy metal powder suitable for metal additive manufacturing, characterized in that, It is prepared by the preparation method according to any one of claims 1-4.

6. The application of the tantalum alloy metal powder according to claim 5 in additive manufacturing; The process of preparing a solid part using the tantalum alloy metal powder includes: Based on the established 3D model, the additive manufacturing process path is set, and the target solid part is processed and shaped using laser additive manufacturing technology.

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