High-performance titanium-aluminum-niobium alloy and additive manufacturing method thereof

Abstract

The invention discloses a high-performance titanium-aluminum-niobium alloy and an additive manufacturing method thereof. The method comprises the following steps: selecting titanium-aluminum-niobium alloy powder and pure aluminum powder; powder mixing is conducted, specifically, the titanium-aluminum-niobium alloy powder and pure aluminum powder are evenly mixed, and mixed powder is obtained; the mixed powder is subjected to laser melting additive manufacturing, and a printing-state blank is obtained; and heat treatment. The titanium-aluminum-niobium alloy powder and the pure aluminum powder are used, the Nb segregation risk is reduced from the source, raw materials are free of hydrogen, and the air hole defect in the subsequent forming process is avoided; in the powder mixing process, mild ball milling achieves the dual purposes of interface strengthening and component uniformity; sLM printing process parameter optimization: aiming at the high melting point characteristic of a niobium-containing system, breaking through traditional general parameter design, and adopting rapid solidification parameter design to inhibit macroscopic segregation of Nb, Al and other elements; the two-step heat treatment synchronously realizes defect elimination and phase structure regulation and control; and performance and industrialization feasibility are both considered, and the batch application path of the high-performance titanium-aluminum-niobium alloy in the high-end manufacturing field can be expanded.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of alloy preparation, and particularly relates to a high-performance titanium-aluminum-niobium alloy and an additive manufacturing method thereof. BACKGROUND

[0002] As an important branch of metal additive manufacturing, selective laser melting (SLM) additive manufacturing technology has great application potential in high-end manufacturing fields such as aerospace, automobile manufacturing and biomedical engineering, due to its ability to near-net shape complex structural parts, high material utilization rate and precise size control. This technology realizes the direct manufacturing of three-dimensional solid parts by selectively melting metal powder layer by layer with a high-energy laser beam, which can break through the limitations of traditional forging and casting processes in complex structure forming and provide a new technical path for the rapid preparation of high-performance metal components.

[0003] Titanium-aluminum intermetallics-based titanium-aluminum alloys have become an ideal candidate material for replacing traditional nickel-based high-temperature alloys and reducing the weight of hot-end components such as aerospace engines, due to their low density (3.9-4.7 g / cm³), high specific strength, excellent high-temperature mechanical properties (can work at 600-800 ℃ for a long time) and good oxidation resistance. The introduction of niobium (Nb) element is a key means to optimize the performance of titanium-aluminum-based alloys. Niobium can effectively improve the room temperature plasticity and fracture toughness of the alloy, and enhance the high-temperature oxidation resistance and creep resistance, so that the alloy can maintain structural stability at extreme working conditions above 800 ℃, further expanding the application prospect of titanium-aluminum-based alloys in high-pressure turbine blades, combustion chambers and other core hot-end components of aerospace engines.

[0004] However, titanium-aluminum intermetallics itself (even after adding niobium element) still has inherent defects such as high room temperature brittleness and poor plasticity, and the difference between the high melting point of niobium (2468 ℃) and the melting point of the titanium-aluminum matrix exacerbates the thermal stress concentration problem of the material during forming. Its traditional forming processes (such as casting and forging) face many challenges: casting is prone to defects such as porosity and segregation, which leads to fluctuations in mechanical properties, and the uniformity of niobium element distribution is difficult to control; forging needs to be carried out at high temperature, which is energy-consuming and requires harsh conditions for the mold, especially for complex structural parts. Therefore, applying selective laser melting additive manufacturing technology to the forming of niobium-containing titanium-aluminum intermetallics has become an important exploration direction to solve the problem of complex structure preparation and performance optimization.

[0005] CN102717086A discloses a short process for preparing high niobium titanium aluminum alloy spherical powder, the core of which is to prepare high niobium titanium aluminum alloy spherical powder suitable for powder metallurgy, and the TiH2, pure Al and NbAl intermediate alloy used are primary raw materials, and alloying can be realized only by high-energy ball milling + heat treatment, but the heat treatment dehydrogenation and alloying process is easy to cause Nb segregation due to the difference in element diffusion rate, and there is impurity gas hydrogen, which cannot be applied to SLM forming preparation. SUMMARY

[0006] To solve the problems in the prior art, the purpose of the present application is to provide a high-performance titanium aluminum niobium alloy and an additive manufacturing method thereof.

[0007] To achieve the above purposes and achieve the above technical effects, the technical scheme adopted by the present application is as follows: An additive manufacturing method of a high-performance titanium aluminum niobium alloy, comprising the following steps: 1) selecting titanium aluminum niobium alloy powder and pure aluminum powder; 2) mixing powder: uniformly mixing the titanium aluminum niobium alloy powder and the pure aluminum powder to obtain a mixed powder; 3) laser melting additive manufacturing of the mixed powder to obtain a printed blank; 4) heat treatment.

[0008] Further, in step 1), the titanium aluminum niobium alloy powder comprises the following components by mass percentage: Titanium 60-61.5% Aluminum 25% Niobium 13% Trace elements 0.5-2%.

[0009] Further, the trace elements are one or a combination of V, Cr and Mo.

[0010] Further, the titanium aluminum niobium alloy powder is selected to be a spherical titanium aluminum niobium alloy powder with a particle size of 20-63 μm, a sphericity of ≥95%, and an oxygen content of ≤0.15wt%.

[0011] Further, in step 1), the pure aluminum powder is selected to be a spherical aluminum powder with a particle size of 15-53 μm, a purity of ≥99.5%, a sphericity of ≥98%, and an oxygen content of ≤0.08wt%.

[0012] Further, in step 2), the titanium aluminum niobium alloy powder and the pure aluminum powder are placed in a planetary ball mill in a mass ratio of 3.75-4.85:1, and are uniformly mixed under argon protection to obtain a mixed powder.

[0013] Further, the ball-to-material ratio is 5:1-10:1, the rotating speed is 200-300 r / min, and the ball milling time is 2-4 h.

[0014] Further, in step 3), the mixed powder obtained in step 2) is subjected to SLM printing in an argon protective atmosphere, the laser power is 200-350 W, the scanning speed is 800-1500 mm / s, the layer thickness is 30-50 μm, the scanning interval is 80-120 μm, rapid solidification is realized to inhibit composition segregation, bidirectional cross scanning is adopted to reduce anisotropy, and finally the density of the printed green part reaches ≥97%, and a mixed structure of titanium-aluminum-niobium intermetallic compound and aluminum phase is preliminarily formed.

[0015] Further, in step 4), the heat treatment comprises the following steps: According to the internal defects and phase structure characteristics of the SLM printed green part, two-step heat treatment is adopted to realize performance optimization. Hot isostatic pressing (HIP) treatment: under the condition of 1100-1250 ℃ and 100-200 MPa, heat preservation is carried out for 2-4 h, and the furnace is cooled down; Solution heat treatment: after being heated to 900-1050 ℃ and heat preserved for 2-4 h, rapid cooling is carried out, and finally a microstructure with a γ (TiAl) phase as a matrix and a small amount of α2 (Ti3Al) phase uniformly distributed is obtained.

[0016] The application further discloses a high-performance titanium-aluminum-niobium alloy prepared by the additive manufacturing method.

[0017] Compared with the prior art, the application has the following beneficial effects: a. Functional customization of alloy powder composition: titanium-aluminum-niobium alloy powder with Ti (60-61.5%), Al (25%), Nb (13%) and trace elements (0.5-2%) as main components is selected to realize pre-adjustment and control of the phase structure. By fixing the Ti-Al atomic ratio, the target γ (TiAl) phase composition is matched in advance, and the phase structure disorder caused by insufficient element diffusion in SLM forming is avoided; the trace elements can improve the performance in a targeted manner, V can reduce the stacking fault energy to improve the room temperature plasticity, Cr can refine the grains to reduce forming defects, and Mo can enhance the high-temperature creep resistance, thereby solving the pain points of traditional titanium-aluminum-niobium alloy, such as brittleness and hardening, and high-temperature performance deficiency; the powder physical properties are adapted to SLM, the particle size is limited to 20-63 μm, the sphericity is ≥95%, the oxygen content is ≤0.15 wt%, the loose bulk density is ≥2.5 g / cm 3 , and the requirements of SLM powder laying fluidity and laser absorption rate are met; b. Dual-function design of pure aluminum powder: Introduce spherical pure aluminum powder with a particle size of 15-53 μm and a purity of ≥99.5%, break through the traditional "single powder forming" idea, first realize precise adjustment of composition, mix with titanium-aluminum-niobium alloy powder according to a mass ratio of 3.75-4.85:1, precisely supplement Al content, provide sufficient Al source for in-situ generation of γ phase, avoid Al element burning loss caused by SLM rapid solidification, secondly actively relieve thermal stress, use the low melting point (660℃) characteristics of Al to form a "low melting point Al phase-high melting point titanium-aluminum-niobium phase" temperature gradient buffer layer in the SLM melt pool, reduce the thermal stress concentration caused by the melting point difference between Ti (1668℃), Nb (2468℃) and Al, and reduce the cracking risk from the root; c. The process innovation of the present application is reflected in the targeted optimization and collaborative design of the whole process parameters: Powder mixing process: mild ball milling realizes the dual goals of interface strengthening and composition uniformity; SLM printing process parameter optimization: for the high melting point characteristics of the niobium-containing system, break through the traditional general parameter design, adopt rapid solidification parameter design to inhibit the macroscopic segregation of Nb, Al and other elements; Two-step heat treatment simultaneously realizes defect elimination and phase structure regulation; d. The traditional niobium-containing titanium-aluminum alloy is difficult to balance high temperature strength and room temperature plasticity due to uneven phase structure and many defects. The present application builds a unique performance regulation mechanism through material-technology collaboration, and the innovation points are reflected in: High temperature performance strengthening: through the high content design of 13% Nb and the synergy of Mo element, the tensile strength of the component at 800℃ is ≥600MPa, which is more than 20% higher than that of the traditional titanium-aluminum-niobium alloy, and the high temperature oxidation resistance is significantly enhanced, which can meet the extreme working condition requirements of the hot end parts of the aero-engine; Room temperature plasticity breakthrough: relying on the synergistic effect of V element to improve plasticity, Cr to refine grains, and HIP to eliminate defects, the room temperature elongation is increased to more than 3.5%, breaking the bottleneck of room temperature elongation <2% of traditional niobium-containing titanium-aluminum alloy, solving the industry pain point of high strength and low plasticity; Density and performance stability improvement: through SLM rapid solidification and HIP defect elimination, the density is ≥99%, which is much higher than that of traditional powder metallurgy (density about 85-90%), and the hardness fluctuation of different regions of the component is ≤5%, the performance stability is improved by more than 15% compared with the existing SLM process; e. The present application uses titanium-aluminum-niobium alloy powder + pure aluminum powder, which reduces the risk of Nb segregation from the source, and avoids the porosity defect in the subsequent forming; f. Economic efficiency and industrialization adaptation: The existing titanium-aluminum-niobium alloy additive manufacturing process has problems of high energy consumption, long cycle, low material utilization, etc. The innovation of the present application lies in balancing performance and industrialization feasibility. Energy consumption and cost reduction: without the high-temperature preheating equipment of traditional processes, energy consumption is reduced by more than 40%; material utilization is increased from 30% in traditional powder metallurgy to more than 90%, greatly reducing raw material waste and reducing the cost per component; Production cycle is shortened: compared with the step-by-step printing and annealing process, through the integrated process of SLM+HIP+HT, the production cycle is shortened by 50%, further meeting the demand for rapid preparation of components in the aerospace field; Application scenario adaptability: for complex structures such as aircraft engine blades and combustion chambers, through near-net shaping and performance stability control, there is no need for subsequent large amount of machining, which expands the batch application path of high-performance titanium-aluminum-niobium alloy in high-end manufacturing field. DETAILED DESCRIPTION

[0018] The present application will be described in detail below, so that the advantages and features of the present application can be more easily understood by those skilled in the art, and the scope of protection of the present application can be more clearly and explicitly defined.

[0019] The following gives a brief summary of one or more aspects to provide a basic understanding of these aspects. This summary is not an exhaustive overview of all contemplated aspects, and is neither intended to identify key or critical elements of all aspects nor to delineate the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that is given later.

[0020] The present application discloses an additive manufacturing method of high-performance titanium-aluminum-niobium alloy, comprising the following steps: 1) Selecting titanium-aluminum-niobium alloy powder: selecting spherical titanium-aluminum-niobium alloy powder with a particle size of 20-63 μm, the main components being titanium (60-61.5%), aluminum (25%), niobium (13%), and trace elements 0.5-2% (one or a combination of several of V, Cr, Mo), the titanium-aluminum atomic ratio is pre-adjusted to match the target gamma (TiAl) phase composition, and the trace elements are used to improve the room temperature plasticity and high temperature strength of the material. The powder needs to meet high sphericity (≥95%), low oxygen content (≤0.15wt%) and narrow particle size distribution to ensure the flowability of the bulk density ≥2.5 g / cm 3 , laying a foundation for the composition uniformity in the SLM process; Pure aluminum powder: Select spherical aluminum powder with a particle size of 15-53 pm, purity ≥ 99.5%, sphericity ≥ 98% and oxygen content ≤ 0.08wt%. Its core role is to accurately adjust the aluminum content of the system by mixing powder, which not only provides component guarantee for in-situ generation of γ phase, but also uses the low melting point characteristics of aluminum to relieve thermal stress concentration caused by the melting point difference of titanium, aluminum and niobium in the printing process, and reduce the risk of cracking; 2) Mixing powder: Titanium aluminum niobium alloy powder and pure aluminum powder are placed in a planetary ball mill in an argon atmosphere at a mass ratio of 3.75-4.85:1 to achieve uniform mixing. The key parameters are set as follows: ball-to-powder ratio 5:1-10:1, rotation speed 200-300 r / min, and ball milling time 2-4 h. This process refines the powder surface morphology through mechanical force (increases the specific surface area and improves the laser absorption rate), promotes the interfacial bonding of titanium aluminum niobium alloy powder and pure aluminum powder, and reduces the SLM molten pool interface stress; since Nb is uniformly distributed in the alloy powder, the segregation of niobium elements during the mixing stage can be avoided from the source, and the added V, Cr and Mo elements can be uniformly dispersed, laying a foundation for the subsequent formation of alloy materials with excellent performance; 3) Laser melting additive manufacturing: For the high melting point characteristics of the niobium-containing system, the traditional general parameter design is broken through, and rapid solidification parameter design is adopted: The mixed powder is printed by SLM in an argon atmosphere (oxygen content ≤ 0.01%) with core parameters optimized for the high melting point characteristics of the niobium-containing system: Laser power 200-350 W, scanning speed 800-1500 mm / s, with layer thickness 30-50 pm and scanning spacing 80-120 pm, to achieve rapid solidification (cooling rate 10 4 ~10 6 ℃ / s) to suppress composition segregation; Two-way cross scanning (interlayer rotation 67°) is used to reduce anisotropy; Through parameter coordination control, the density of the printed green part can reach ≥ 97%, and the mixed organization of titanium aluminum niobium intermetallic compound and aluminum phase is preliminarily formed, laying a foundation for the subsequent phase structure regulation of heat treatment; 4) Heat treatment: According to the internal defects and phase structure characteristics of the SLM printed green part, two-step heat treatment is adopted to realize performance optimization: Hot isostatic pressing (HIP) treatment: heat preservation at 1100-1250℃, 100-200MPa for 2-4h, and then cooling in the furnace to eliminate defects such as pores and microcracks, so that the density is increased to ≥ 99%, and the uniform diffusion of aluminum and niobium atoms in the matrix is promoted, laying a foundation for the subsequent phase structure regulation; Solution heat treatment: heated to 900~1050℃ for 2~4h and then rapidly cooled (air cooling or oil cooling), finally obtain a microstructure with a base of gamma (TiAl) phase and a small amount of alpha2 (Ti3Al) phase uniformly distributed, realize the full play of the strengthening effect of niobium element, avoid the plasticity decline caused by excessive alpha2 phase in traditional heat treatment, and balance the high temperature strength and room temperature plasticity of the alloy.

[0021] The application further discloses a high-performance titanium-aluminum-niobium alloy prepared by the additive manufacturing method.

[0022] Example 1 An additive manufacturing method of a high-performance titanium-aluminum-niobium alloy, comprising the following steps: 1) selecting titanium-aluminum-niobium alloy powder: selecting spherical titanium-aluminum-niobium alloy powder with a particle size of 40 μm, the main components are Ti 60.5%, Al 25%, Nb 13%, V 1.5%, the sphericity is 98%, and the oxygen content is 0.12 wt%; selecting pure aluminum powder: selecting spherical aluminum powder with a particle size of 30 μm, the purity is 99.6%, the sphericity is 98%, and the oxygen content is 0.08 wt%; 2) mixing powder: The titanium-aluminum-niobium alloy powder and the pure aluminum powder are placed in a planetary ball mill at a mass ratio of 4:1, and the titanium-aluminum-niobium alloy powder and the pure aluminum powder are uniformly mixed under argon protection, to obtain a mixed powder, and the key parameters are set as follows: a ball-to-powder ratio of 7:1, a rotation speed of 250 r / min, and a ball milling time of 3 h. The process refines the powder surface morphology (increases the specific surface area and improves the laser absorption rate) through mechanical force, promotes the interfacial bonding of the titanium-aluminum-niobium alloy powder and the pure aluminum powder, and reduces the SLM molten pool interfacial stress; since the Nb in the alloy powder is uniformly distributed, the segregation of niobium elements in the mixing stage can be avoided from the source, and the added V, Cr and Mo elements can be uniformly dispersed, laying a foundation for the subsequent formation of an alloy material with excellent performance; after the powder mixing is completed, the powder is taken out, and the interface between the pre-alloy powder and the pure aluminum powder is tightly combined without obvious segregation phenomenon; 3) laser melting additive manufacturing: In view of the high melting point characteristics of the niobium-containing system, the traditional general parameter design is broken through, and rapid solidification parameter design is adopted: An SLM device is used to build a CAD model of an aero-engine blade, and the model is sliced. The mixed powder is subjected to SLM printing in an argon protection atmosphere (oxygen content 0.01%), and the printing parameters are set as follows: a laser power of 300 W, a scanning speed of 1200 mm / s, a layer thickness of 40 μm and a scanning interval of 80 μm, to realize rapid solidification (cooling rate 10 4 ℃ / s) to inhibit composition segregation; Bidirectional cross scanning (interlayer rotation of 67°) is adopted to reduce anisotropy. During the printing process, the temperature of the molten pool and the state of powder spreading are monitored in real time to ensure the stability of the printing process. Through parameter coordination control, the density of the printed green part can reach ≥97%, and the mixed structure of titanium-aluminum-niobium intermetallic compound and aluminum phase is preliminarily formed, laying a foundation for subsequent phase structure regulation. 4) Heat treatment: According to the internal defects and phase structure characteristics of the SLM printed green part, two-step heat treatment is adopted to realize performance optimization: Hot isostatic pressing (HIP) treatment: under the condition of 1150℃ and 150MPa, heat preservation for 3h, and after furnace cooling, the defects such as pores and micro-cracks can be eliminated, so that the density is improved to 99.2%, and at the same time, the uniform diffusion of aluminum and niobium atoms in the matrix is promoted, laying a foundation for subsequent phase structure regulation; Solution heat treatment: heated to 950℃ and preserved for 2h, and then rapidly cooled (oil cooling), finally the microstructure of γ (TiAl) phase as the matrix and a small amount of α2 (Ti3Al) phase uniformly distributed is obtained, the volume fraction of α2 phase is about 8%, the strengthening effect of niobium element is fully played, and the plasticity decline caused by excessive α2 phase in traditional heat treatment is avoided, and the high temperature strength and room temperature plasticity of the alloy are considered.

[0023] The embodiment also discloses a high-performance titanium-aluminum-niobium alloy prepared by the additive manufacturing method of the high-performance titanium-aluminum-niobium alloy.

[0024] Embodiment 2 An additive manufacturing method of a high-performance titanium-aluminum-niobium alloy, comprising the following steps: 1) Selecting titanium-aluminum-niobium alloy powder: selecting spherical titanium-aluminum-niobium alloy powder with a particle size of 20-63μm, the main components are Ti61%, Al 25%, Nb 13%, Cr 1%, the sphericity is 96%, and the oxygen content is 0.13wt%; Selecting pure aluminum powder: selecting spherical aluminum powder with a particle size of 40μm, the purity is 99.5%, the sphericity is 98%, and the oxygen content is 0.08wt%; 2) Mixing powder: The titanium-aluminum-niobium alloy powder and the pure aluminum powder are placed in a planetary ball mill at a mass ratio of 3.8:1, the titanium-aluminum-niobium alloy powder and the pure aluminum powder are 800g in total, and are uniformly mixed under argon protection to obtain a mixed powder, and the key parameters are set as follows: ball-to-material ratio 8:1, rotation speed 280r / min, and ball milling time 3.5h; 3) Laser melting additive manufacturing: According to the high melting point characteristics of the niobium-containing system, the traditional general parameter design is broken through, and rapid solidification parameter design is adopted: The mixed powder is subjected to SLM printing in an argon protection atmosphere (oxygen content 0.01%), and the core parameters are optimized and designed according to the high melting point characteristics of the niobium-containing system: Laser power 320W, scanning speed 1300mm / s, with 45μm layer thickness and 120μm scanning interval, to realize rapid solidification (cooling rate 10 6 ℃ / s) to inhibit composition segregation; Two-way cross scanning (interlayer rotation 67°) is used to reduce anisotropy; During printing, the molten pool temperature is monitored by an infrared thermal imager to ensure that the temperature fluctuation is controlled within ±5℃; Through parameter coordination control, the density of the printed blank can reach ≥97%, and a mixed structure of titanium-aluminum-niobium intermetallic compound and aluminum phase is preliminarily formed, laying a foundation for subsequent phase structure regulation; 4) Heat treatment: According to the internal defects and phase structure characteristics of the SLM printed blank, two-step heat treatment is used to realize performance optimization: Hot isostatic pressing (HIP) treatment: under the condition of 1200℃ and 180MPa, heat preservation for 2.5h, and after furnace cooling, the defects such as pores and micro-cracks can be eliminated, the density is improved to 99.3%, and at the same time, the uniform diffusion of aluminum and niobium atoms in the matrix is promoted, laying a foundation for subsequent phase structure regulation; Solution heat treatment: heated to 1000℃ and heat preserved for 3h, and then rapidly cooled (oil cooling), finally a microstructure with γ(TiAl) phase as the matrix and a small amount of α2(Ti3Al) phase uniformly distributed is obtained, realizing the full play of the strengthening effect of niobium element, avoiding the plasticity reduction caused by excessive α2 phase in traditional heat treatment, and taking into account the high temperature strength and room temperature plasticity of the alloy.

[0025] The embodiment also discloses a high-performance titanium-aluminum-niobium alloy prepared by the additive manufacturing method.

[0026] The rest is the same as in example 1.

[0027] The blades prepared in examples 1-2 are respectively subjected to performance tests, and the results are as follows: Example 1: The room temperature tensile test shows that the tensile strength reaches 900MPa, and the elongation is 3.8%; the high-temperature tensile strength at 800℃ is 650MPa, compared with the same blades prepared by traditional processes, the room temperature strength is increased by 15%, the high-temperature strength is increased by 20%, and the internal defects are obviously reduced, meeting the high-performance requirements of the aero-engine blades.

[0028] Example 2: The yield strength reaches 750 MPa and the elongation is 3.6% at room temperature; the tensile strength remains above 550 MPa in the high-temperature environment (700 DEG C) simulating the service of a spacecraft, the hardness difference of different parts of the component is controlled within 4%, the performance stability is good, the strict requirements of the spacecraft on the high strength and high stability of the structural component are met, and compared with the traditional manufacturing process, the material utilization rate is increased from 35% to 92% and the production cycle is shortened by 40%.

[0029] The parts or structures not specifically described in the present application can adopt the prior art or existing products, and will not be described here.

[0030] The above is only an embodiment of the present application, and does not limit the patent scope of the present application, and any equivalent structure or equivalent process transformation using the content of the present application specification, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for additive manufacturing of high-performance titanium-aluminum-niobium alloy, characterized in that, Includes the following steps: 1) Select titanium-aluminum-niobium alloy powder and pure aluminum powder; 2) Powder mixing: Titanium-aluminum-niobium alloy powder and pure aluminum powder are mixed evenly to obtain mixed powder; 3) The mixed powder is subjected to laser melting additive manufacturing to obtain a printed blank; 4) Heat treatment.

2. The additive manufacturing method for a high-performance titanium-aluminum-niobium alloy according to claim 1, characterized in that, In step 1), the titanium-aluminum-niobium alloy powder comprises the following components by mass percentage: Titanium 60~61.5% 25% aluminum Niobium 13% Trace elements: 0.5-2%.

3. The additive manufacturing method for a high-performance titanium-aluminum-niobium alloy according to claim 2, characterized in that, The trace elements are one or a combination of V, Cr, and Mo.

4. The additive manufacturing method for a high-performance titanium-aluminum-niobium alloy according to claim 1, characterized in that, The titanium-aluminum-niobium alloy powder is selected as spherical titanium-aluminum-niobium alloy powder with a particle size of 20~63μm, sphericity ≥95%, and oxygen content ≤0.15wt%.

5. The additive manufacturing method for a high-performance titanium-aluminum-niobium alloy according to claim 1, characterized in that, In step 1), the pure aluminum powder is selected as spherical aluminum powder with a particle size of 15~53μm, purity ≥99.5%, sphericity ≥98%, and oxygen content ≤0.08wt%.

6. The additive manufacturing method for a high-performance titanium-aluminum-niobium alloy according to claim 1, characterized in that, In step 2), titanium-aluminum-niobium alloy powder and pure aluminum powder are placed in a planetary ball mill at a mass ratio of 3.75 to 4.85:1 and uniformly mixed under argon protection to obtain mixed powder.

7. The additive manufacturing method for a high-performance titanium-aluminum-niobium alloy according to claim 6, characterized in that, The ball-to-material ratio is 5:1 to 10:1, the rotation speed is 200 to 300 r / min, and the ball milling time is 2 to 4 hours.

8. The additive manufacturing method for a high-performance titanium-aluminum-niobium alloy according to claim 1, characterized in that, In step 3), the mixed powder obtained in step 2) is subjected to SLM printing in an argon protective atmosphere. The laser power is 200~350W, the scanning speed is 800~1500mm / s, and the layer thickness is 30~50μm with a scanning interval of 80~120μm to achieve rapid solidification and suppress component segregation. Bidirectional cross scanning is used to reduce anisotropy. The final printed blank has a density of ≥97% and initially forms a mixed structure of titanium-aluminum-niobium intermetallic compounds and aluminum phase.

9. The additive manufacturing method for a high-performance titanium-aluminum-niobium alloy according to claim 1, characterized in that, In step 4), the heat treatment includes the following steps: To address the internal defects and phase structure characteristics of SLM-printed preforms, a two-step heat treatment process is employed to optimize performance. Hot isostatic pressing: Hold at 1100~1250℃ and 100~200MPa for 2~4 hours, then cool with the furnace; Solution heat treatment: Heat to 900~1050℃ and hold for 2~4h, then cool rapidly to finally obtain a microstructure with γ phase as the matrix and a small amount of α2 phase evenly distributed.

10. A high-performance titanium-aluminum-niobium alloy prepared by an additive manufacturing method according to any one of claims 1-9.