High-Temperature Performance Nano-Ceramic Particle-Reinforced Titanium-Aluminum Alloy and its Preparation Method

Abstract

This invention provides a nano-ceramic particle-reinforced titanium-aluminum alloy with excellent high-temperature performance and its preparation method, comprising: mixing Ti powder, Nb powder and B powder to obtain a first mixed powder; and mixing the first mixed powder with Ti... 48 Al 48 Cr2Nb2 pre-alloyed powder was mixed in different proportions to obtain second, third, and fourth mixed powders. The second, third, and fourth mixed powders were placed on titanium strips in sequence and in a certain proportion and then encapsulated to obtain continuous mixed powder titanium pillars. The continuous mixed powder titanium pillars were added to titanium-aluminum alloys through vacuum induction melting to prepare high-temperature performance nano-ceramic particle-reinforced titanium-aluminum alloys. These reinforced titanium-aluminum alloys have excellent strength and plasticity at high temperatures, with yield strength, tensile strength, and fracture strain at 800℃ and above being ≥550.6MPa, ≥599.4MPa, and ≥22.8%, respectively.

Description

Technical Field

[0001] This invention relates to the field of high-performance high-temperature alloy technology, specifically to a nano-ceramic particle-reinforced titanium-aluminum alloy with excellent high-temperature performance and its preparation method. Background Technology

[0002] Titanium-aluminum alloys are widely used in structural materials such as aerospace engine blades and automotive turbocharger rotors. However, with the increasing demands of new-generation power systems on operating temperatures, existing titanium-aluminum alloys exhibit significant performance degradation, including strength reduction, at high temperatures. Current technologies primarily address these issues through alloying modification, heat treatment control, and optimization of hot working processes. Regarding alloying modification, the addition of precious metals such as Mo and Ta suppresses performance degradation, but this can lead to component segregation and the formation of complex phases, increasing strength while decreasing ductility. Heat treatment control presents two main problems: first, the process window is narrow, and even slight deviations in process parameters can cause grain coarsening or microstructure inhomogeneity, resulting in a decrease in material performance; second, for large-sized or complex geometrically shaped components, it is difficult to find suitable heating equipment to achieve uniform control of the overall material properties. The technical challenge of hot working processes lies in the high precision required for parameters such as forging temperature and strain rate. This process is prone to defects such as uneven alloy rheology, residual stress, cold cap formation, and hard, brittle layers. As a result, while significantly improving strength, the alloy may suffer a reduction in plasticity or toughness, making it unsuitable for industrial production. Therefore, achieving the industrial production of titanium-aluminum alloys that maintain high strength, plasticity, and toughness at both room and high temperatures, while simplifying the process and reducing the addition of high-cost elements, is a pressing technical challenge that needs to be overcome. Summary of the Invention

[0003] To address the aforementioned technical challenges, this invention provides a nano-ceramic particle-reinforced titanium-aluminum alloy with excellent high-temperature performance, the preparation method of which includes the following steps:

[0004] Step 1: Ti powder, Nb powder and B powder are ball-milled in a molar ratio of 1:1:4-4.5 to obtain the first mixed powder. The ball milling process is as follows: the ball milling time is 6-9 hours, the rotation speed is 40-70 rpm, the particle size range of Ti powder is 10-40 μm, the particle size range of Nb powder is 20-70 μm, and the particle size of B powder is 0.1-1.5 μm.

[0005] Step 2: Mix the first mixed powder prepared in Step 1 with Ti particles with a particle size of 50-140 μm. 48 Al 48Cr2Nb2 pre-alloyed powder was ball-milled and mixed at mass ratios of 9-15:1, 4-8:1 and 2-6:1 to obtain second, third and fourth mixed powders, respectively. The ball-milling and mixing process was carried out for 6-10 hours and the ball milling speed was 40-80 rpm.

[0006] Step 3: Arrange the second, third, and fourth mixed powders obtained in Step 2 in a mass ratio of 1-2:1-2:6-8 on a titanium strip and encapsulate them to obtain a continuous mixed powder titanium column;

[0007] Step 4: After vacuum induction melting of the TiAl alloy, add the continuously mixed powdered titanium pillars obtained in Step 3. The mass ratio of the continuously mixed powdered titanium pillars to the TiAl alloy is 0.5%–0.8%:1. After the continuously mixed powdered titanium pillars melt, hold the temperature for 4–10 minutes to generate and uniformly distribute nano-ceramic particles. After casting, a nano-ceramic particle-reinforced titanium-aluminum alloy with excellent high-temperature performance is obtained. The vacuum induction melting process is as follows: under argon protection, heating is started at 3–10 kW, and the power is increased by 5–8 kW every 3–7 minutes until the alloy is completely melted. Then, the temperature is held for 3–7 minutes. The TiAl alloy composition, by mass percentage, includes: Al: 33.0–34.5 wt.%; Cr: 2.3–2.6 wt.%; Nb: 4.7–5.1 wt.%; the remainder is Ti.

[0008] The microstructure of the high-temperature performance nano-ceramic particle-reinforced titanium-aluminum alloy is lamellar, with an average lamellar size ≤122μm. The internal structure contains uniformly distributed nano-ceramic particles with a particle size of 30-400 nm. At ≥800℃, the yield strength, tensile strength, and fracture strain of the high-temperature performance nano-ceramic particle-reinforced titanium-aluminum alloy are ≥550.6MPa, ≥599.4MPa, and ≥22.8%, respectively.

[0009] Furthermore, in step one, the particle size range of Ti powder is 15-30 μm, the particle size range of Nb powder is 25-50 μm, and the particle size of B powder is 0.2-1.0 μm.

[0010] Furthermore, the ball milling mixing process described in step two takes 7-9 hours and the ball milling speed is 50-70 rpm.

[0011] Furthermore, the vacuum induction melting process described in step four is as follows: under argon protection, heating is started at a power of 5-8kW, and the power is increased by 5.5-7kW every 4-6 minutes until the alloy is completely melted, and then held at that temperature for 4-6 minutes. Attached Figure Description

[0012] Figure 1This is a microstructure image of the nano-ceramic particle-reinforced titanium-aluminum alloy 1 with excellent high-temperature performance in Example 1 of the present invention.

[0013] Figure 2 This is an engineering tensile stress-strain curve of the nano-ceramic particle-reinforced titanium-aluminum alloy 1 with excellent high-temperature performance in Embodiment 1 of the present invention at 800℃.

[0014] Figure 3 This is a microstructure image of the nano-ceramic particle-reinforced titanium-aluminum alloy 2 with excellent high-temperature performance in Example 2 of the present invention.

[0015] Figure 4 This is an engineering tensile stress-strain curve of the nano-ceramic particle-reinforced titanium-aluminum alloy 2 with excellent high-temperature performance in Embodiment 2 of the present invention at 810℃.

[0016] Figure 5 The image shows the microstructure of the nano-ceramic particle-reinforced titanium-aluminum alloy 3 with excellent high-temperature performance in Example 3 of this invention.

[0017] Figure 6 This is an engineering tensile stress-strain curve of the nano-ceramic particle-reinforced titanium-aluminum alloy 3 with excellent high-temperature performance in Example 3 of the present invention at 820℃.

[0018] Figure 7 This is a microstructure morphology diagram of the titanium-aluminum alloy in Comparative Example 1 of the present invention;

[0019] Figure 8 This is a diagram showing the tensile stress-strain curve of the titanium-aluminum alloy in Comparative Example 1 of the present invention at 800℃. Detailed Implementation

[0020] The following will describe specific embodiments of the present invention in detail. Obviously, these embodiments are only some, not all, examples of the present invention. Other implementations derived by those skilled in the art based on these embodiments without departing from the concept of the present invention should be considered within the scope of protection of the present invention.

[0021] Example 1

[0022] The preparation method of the nano-ceramic particle-reinforced titanium-aluminum alloy 1 with excellent high-temperature performance includes the following steps:

[0023] Step 1: Ti powder, Nb powder and B powder are ball-milled in a molar ratio of 1:1:4 to obtain the first mixed powder. The ball milling process is as follows: ball milling time is 9 hours, rotation speed is 60 rpm, Ti powder has a particle size of 10 μm, Nb powder has a particle size of 40 μm, and B powder has a particle size of 0.1 μm.

[0024] Step 2: Mix the first mixed powder prepared in Step 1 with Ti particles with a particle size of 50 μm.48 Al 48 Cr2Nb2 pre-alloyed powder was ball-milled at mass ratios of 9:1, 4:1 and 2:1 to obtain second, third and fourth mixed powders, respectively. The ball-milling process lasted for 8 hours and the ball milling speed was 50 rpm.

[0025] Step 3: Arrange the second, third, and fourth mixed powders obtained in Step 2 on a titanium strip in a mass ratio of 1:1:8 and encapsulate them to obtain a continuous mixed powder titanium column;

[0026] Step 4: After vacuum induction melting of the TiAl alloy, add the continuously mixed powdered titanium column obtained in Step 3. The mass ratio of the continuously mixed powdered titanium column to the TiAl alloy is 0.8%:1. After the continuously mixed powdered titanium column melts, hold it at the temperature for 4 minutes and then cast to obtain a nano-ceramic particle-reinforced titanium-aluminum alloy 1 with excellent high-temperature performance. The vacuum induction melting process is as follows: under argon protection, start heating with a power of 5kW, increase the power by 5kW every 4 minutes until the alloy is completely melted, and then hold it at the temperature for 6 minutes. The TiAl alloy composition includes, by mass percentage: Al: 33.0wt.%, Cr: 2.6wt.%, Nb: 4.8wt.%, with the balance being Ti.

[0027] The microstructure of the high-temperature performance nano-ceramic particle-reinforced titanium-aluminum alloy 1 prepared in this embodiment is as follows: Figure 1 As shown: the microstructure is lamellar, with an average lamellar cluster size of ~122μm, and the internal structure contains uniformly distributed nano-ceramic particles; Figure 2 The results show that at 800℃, the yield strength, tensile strength, and fracture strain of the nano-ceramic particle-reinforced titanium-aluminum alloy 1 with excellent high-temperature performance are 550.6 MPa, 599.4 MPa, and 25.5%, respectively.

[0028] Example 2

[0029] The preparation method of the nano-ceramic particle-reinforced titanium-aluminum alloy 2 with excellent high-temperature performance includes the following steps:

[0030] Step 1: Ti powder, Nb powder and B powder are ball-milled in a molar ratio of 1:1:4.1 to obtain the first mixed powder. The ball milling process is as follows: ball milling time is 8 hours, rotation speed is 40 rpm, Ti powder particle size is 30 μm, Nb powder particle size is 20 μm, and B powder particle size is 0.5 μm.

[0031] Step 2: Mix the first mixed powder prepared in Step 1 with Ti particles with a particle size of 100 μm. 48 Al 48Cr2Nb2 pre-alloyed powder was ball-milled at mass ratios of 9.5:1, 4.5:1 and 2.5:1 to obtain second, third and fourth mixed powders, respectively. The ball-milling process lasted for 9 hours and the ball milling speed was 70 rpm.

[0032] Step 3: Arrange the second, third, and fourth mixed powders obtained in Step 2 on a titanium strip in a mass ratio of 2:2:6 and encapsulate them to obtain a continuous mixed powder titanium column;

[0033] Step 4: After vacuum induction melting of the TiAl alloy, add the continuously mixed powdered titanium column obtained in Step 3. The mass ratio of the continuously mixed powdered titanium column to the TiAl alloy is 0.5%:1. After the continuously mixed powdered titanium column melts, hold it at the temperature for 7 minutes and then cast to obtain nano-ceramic particle-reinforced titanium-aluminum alloy 2 with excellent high-temperature performance. The vacuum induction melting process is as follows: under argon protection, start heating with a power of 8kW, increase the power by 8kW every 8 minutes until the alloy is completely melted, and then hold it at the temperature for 5 minutes. The TiAl alloy composition, by mass percentage, includes: Al: 34.5wt.%, Cr: 2.4wt.%, Nb: 5.1wt.%, with the balance being Ti.

[0034] The microstructure of the high-temperature performance nano-ceramic particle-reinforced titanium-aluminum alloy 2 prepared in this embodiment is as follows: Figure 3 As shown: the microstructure is lamellar, with an average lamellar cluster size of ~98μm, and the internal structure contains uniformly distributed nano-ceramic particles; Figure 4 The results show that at 810℃, the yield strength, tensile strength, and fracture strain of the nano-ceramic particle-reinforced titanium-aluminum alloy 2 with excellent high-temperature performance are 567.2 MPa, 623.7 MPa, and 24.0%, respectively.

[0035] Example 3

[0036] The preparation method of the nano-ceramic particle-reinforced titanium-aluminum alloy 3 with excellent high-temperature performance includes the following steps:

[0037] Step 1: Ti powder, Nb powder and B powder are ball-milled in a molar ratio of 1:1:4.2 to obtain the first mixed powder. The ball milling process is as follows: ball milling time is 6 hours, rotation speed is 70 rpm, Ti powder particle size is 40 μm, Nb powder particle size is 70 μm, and B powder particle size is 0.3 μm.

[0038] Step 2: Mix the first mixed powder prepared in Step 1 with Ti particles with a particle size of 140 μm. 48 Al 48Cr2Nb2 pre-alloyed powder was ball-milled at mass ratios of 10:1, 5:1 and 3:1 to obtain second, third and fourth mixed powders, respectively. The ball-milling process lasted for 6 hours and the ball milling speed was 40 rpm.

[0039] Step 3: Arrange the second, third, and fourth mixed powders obtained in Step 2 on a titanium strip in a mass ratio of 1.5:1.5:7 and encapsulate them to obtain a continuous mixed powder titanium column.

[0040] Step 4: After vacuum induction melting of the TiAl alloy, add the continuously mixed powdered titanium column obtained in Step 3. The mass ratio of the continuously mixed powdered titanium column to the TiAl alloy is 0.7%:1. After the continuously mixed powdered titanium column melts, hold it at the temperature for 10 minutes and then cast to obtain a nano-ceramic particle-reinforced titanium-aluminum alloy 3 with excellent high-temperature performance. The vacuum induction melting process is as follows: under argon protection, start heating with a power of 6kW, increase the power by 6kW every 3 minutes until the alloy is completely melted, and then hold it at the temperature for 3 minutes. The TiAl alloy composition by mass percentage includes: Al: 34.0wt.%, Cr: 2.3wt.%, Nb: 4.7wt.%, with the balance being Ti.

[0041] The microstructure of the high-temperature performance nano-ceramic particle-reinforced titanium-aluminum alloy 3 prepared in this embodiment is as follows: Figure 5 As shown: the microstructure is lamellar, with an average lamellar cluster size of ~105μm, and the internal structure contains uniformly distributed nano-ceramic particles; Figure 6 The results show that at 820℃, the yield strength, tensile strength, and fracture strain of the nano-ceramic particle-reinforced titanium-aluminum alloy 3 with excellent high-temperature performance are 558.9 MPa, 615.0 MPa, and 22.8%, respectively.

[0042] Comparative Example 1

[0043] The preparation method of titanium-aluminum alloy includes the following steps:

[0044] Step 1: The TiAl alloy is subjected to vacuum induction melting and then cast to obtain a titanium-aluminum alloy. The vacuum induction melting process is as follows: under argon protection, heating is started at 5kW, and the power is increased by 5kW every 5 minutes until the alloy is completely melted, and then held at that temperature for 7 minutes. The TiAl alloy composition, by mass percentage, includes: Al: 34.1wt.%, Cr: 2.6wt.%, Nb: 4.9wt.%, with the balance being Ti.

[0045] The microstructure of the titanium-aluminum alloy prepared in this comparative example is as follows: Figure 7 As shown: the microstructure is lamellar, with an average lamellar cluster size of ~153 μm; Figure 8The results show that at 800℃, the yield strength, tensile strength, and fracture strain of the titanium-aluminum alloy are 479.8 MPa, 557.5 MPa, and 20.8%, respectively.

[0046] The difference between Embodiments 1-3 of the present invention and Comparative Example 1 is that:

[0047] Compared with the lamellar size of the titanium-aluminum alloy obtained in Comparative Example 1, the lamellar size of the nano-ceramic particle-reinforced titanium-aluminum alloy with excellent high-temperature performance obtained in this invention is significantly refined; and at ≥800℃, the high-temperature mechanical properties of the alloy obtained in this invention are significantly better than those of the titanium-aluminum alloy in Comparative Example 1.

[0048] In all embodiments, the nano-ceramic particle-reinforced titanium-aluminum alloy 1 with excellent high-temperature performance prepared in Example 1 has the largest microstructure lamellar cluster size, with an average microstructure lamellar cluster size of ~122 μm, which is 20.3% finer than the titanium-aluminum alloy of Comparative Example 1 (average microstructure lamellar cluster size: ~153 μm). The yield strength, ultimate tensile strength, and fracture strain of the nano-ceramic particle-reinforced titanium-aluminum alloy 1 with excellent high-temperature performance obtained in Example 1 at 800℃ are 550.6 MPa, 599.4 MPa, and 25.5%, respectively, which are increases of 70.8 MPa, 41.9 MPa, and 4.7% compared to the titanium-aluminum alloy of Comparative Example 1, representing increases of 14.8%, 7.5%, and 22.6%, respectively. Therefore, compared with Comparative Example 1, the nano-ceramic particle-reinforced titanium-aluminum alloy 1 with excellent high-temperature performance obtained in this invention has a smaller microstructure lamellar cluster size, and its high-temperature strength and plasticity are significantly better than those of the titanium-aluminum alloy obtained in Comparative Example 1.

[0049] The nano-ceramic particle-reinforced titanium-aluminum alloy 2 with excellent high-temperature performance prepared in Example 2 has an average lamellar size of ~98 μm, which is 35.9% finer than the titanium-aluminum alloy obtained in Comparative Example 1 (average lamellar size: ~153 μm). The yield strength, ultimate tensile strength, and fracture strain of the nano-ceramic particle-reinforced titanium-aluminum alloy 2 with excellent high-temperature performance at 810 °C are 567.2 MPa, 623.7 MPa, and 24.0%, respectively. At temperatures higher than those of the Comparative Example, these values ​​represent increases of 87.4 MPa, 66.2 MPa, and 3.2% compared to the titanium-aluminum alloy of Comparative Example 1, respectively, representing increases of 18.2%, 11.9%, and 15.4%. Therefore, the nano-ceramic particle-reinforced titanium-aluminum alloy 2 with excellent high-temperature performance obtained in this example has smaller lamellar size and significantly better high-temperature mechanical properties than the titanium-aluminum alloy obtained in Comparative Example 1, even at temperatures higher than those of Comparative Example 1.

[0050] The nano-ceramic particle-reinforced titanium-aluminum alloy 3 with excellent high-temperature performance prepared in Example 3 has an average lamellar size of ~105 μm, which is 31.4% finer than the titanium-aluminum alloy of Comparative Example 1 (average lamellar size: ~153 μm). The yield strength, ultimate tensile strength, and fracture strain of the nano-ceramic particle-reinforced titanium-aluminum alloy 3 with excellent high-temperature performance at 820 °C are 558.9 MPa, 615.0 MPa, and 22.8%, respectively. At temperatures higher than those of the comparative example, these values ​​represent increases of 79.1 MPa, 57.5 MPa, and 2.0% compared to the titanium-aluminum alloy of Comparative Example 1, with increases of 16.5%, 10.3%, and 9.6%, respectively. Therefore, this example, using temperatures higher than those of Comparative Example 1, yields a nano-ceramic particle-reinforced titanium-aluminum alloy 3 with smaller lamellar size and significantly better high-temperature mechanical properties than the titanium-aluminum alloy obtained in Comparative Example 1.

[0051] Comparative Example 2

[0052] In 2017, Wenchen Xu et al. published an article in the journal Materials Science and Engineering:A, Volume 705, titled "Improvement of microstructure, mechanical properties, and hotworkability of a TiAl-Nb-Mo alloy through hot extrusion." The TiAl alloy containing Mo (0.85 wt.%) and Y (0.23 wt.%) was hot isostatically pressed for 4 hours at 1250 °C / 175 MPa, followed by extrusion at 1300 °C and an extrusion ratio of 9. Finally, it underwent heat treatment at 1350 °C. The TiAl alloy prepared by this process exhibited a yield strength, tensile strength, and fracture strain of approximately 538.3 MPa, 594.1 MPa, and 4.2% at 800 °C, respectively.

[0053] Compared to Comparative Example 2, this invention omits the addition of precious metal elements such as Mo and Y (alloy content of 1.08 wt.%) and the cumbersome processing steps such as high-temperature static pressing, extrusion, and heat treatment. As a result, even at operating temperatures equal to or higher than Comparative Example 2 (800°C), the alloy obtained by this invention still exhibits significantly better yield strength, tensile strength, and fracture strain than the alloy obtained in Comparative Example 2. Compared to Comparative Example 2, this invention controls the addition of nanoparticles to below 0.8% (lower than Comparative Example 2) and avoids the addition of precious metals such as Mo and Y. Furthermore, the preparation process is simple and low-cost, and this invention achieves simultaneous improvement in the strength and ductility of the alloy at high temperatures. Specific analysis is as follows:

[0054] The high-temperature performance of the nano-ceramic particle-reinforced titanium-aluminum alloy 1 prepared in Example 1 of this invention exhibits yield strength, ultimate tensile strength, and fracture strain of 550.6 MPa, 599.4 MPa, and 25.5% at 800℃, respectively. Compared with the titanium-aluminum alloy of Comparative Example 2, these values ​​represent increases of 12.3 MPa, 5.3 MPa, and 21.3%, respectively, with increases of 2.3%, 0.9%, and 507.1%. Therefore, the high-temperature mechanical properties of the nano-ceramic particle-reinforced titanium-aluminum alloy 1 obtained in this example are significantly superior to those of the titanium-aluminum alloy obtained in Comparative Example 2.

[0055] The high-temperature performance of the nano-ceramic particle-reinforced titanium-aluminum alloy 2 prepared in Example 2 of this invention exhibits yield strength, ultimate tensile strength, and fracture strain of 567.2 MPa, 623.7 MPa, and 24.0% at 810℃ (higher than the application temperature of Comparative Example 2), respectively. These values ​​represent increases of 28.9 MPa, 29.6 MPa, and 19.8% compared to the titanium-aluminum alloy of Comparative Example 2, with increases of 5.4%, 5.0%, and 471.4%, respectively. Therefore, the high-temperature mechanical properties of the nano-ceramic particle-reinforced titanium-aluminum alloy 2 obtained in this example are significantly superior to those of the titanium-aluminum alloy obtained in Comparative Example 2.

[0056] The high-temperature performance of the nano-ceramic particle-reinforced titanium-aluminum alloy 3 prepared in Example 3 of this invention exhibits yield strength, ultimate tensile strength, and fracture strain of 558.9 MPa, 615.0 MPa, and 22.8% at 820℃ (higher than the application temperature of Comparative Example 2), respectively. These values ​​represent increases of 20.6 MPa, 20.9 MPa, and 18.6% compared to the titanium-aluminum alloy of Comparative Example 2, with increases of 3.8%, 3.5%, and 442.9%, respectively. Therefore, the high-temperature mechanical properties of the nano-ceramic particle-reinforced titanium-aluminum alloy 3 obtained in this example are significantly superior to those of the titanium-aluminum alloy obtained in Comparative Example 2.

[0057] Furthermore, the component ratios and process parameters used in the embodiments of the present invention are different, and the microstructure size and process parameters obtained in each embodiment are different. It is not the case that the higher the component content, the better the performance. Therefore, it can be concluded that the excellent effect obtained by the present invention is not determined by a single component, ratio or process parameter, but by the interaction of components, component ratio, process and process parameters. Moreover, the significant improvement effect of the present invention can only be achieved within the scope of protection of the claims of the present invention.

[0058] Table 1 Comparison of high-temperature mechanical properties between the examples and comparative examples.

[0059]

[0060] Compared with comparative examples and existing technologies, this invention, by omitting the addition of precious metal elements, high-temperature and high-pressure heat treatment, high-temperature extrusion, solution treatment, and aging, achieves a uniform lamellar microstructure in the alloy obtained under application temperatures comparable to or higher than those of existing technologies. Furthermore, the alloy obtained by this invention contains uniformly distributed nano-TiB2+NbB2 ceramic particles with a particle size of 30-400 nanometers. The uniform distribution and effective control of the volume fraction of these nanoparticles overcome the problem of significant strength reduction in existing alloys at high temperatures. The alloy obtained by this invention maintains both high strength and high plasticity at high temperatures, saving raw materials and simplifying the process, enabling stable industrial production. In summary, the superior performance of the alloy obtained by this invention is achieved through the synergistic control of component interactions, component ratios, processes, and process parameters. This superior technical effect can only be achieved within the scope of the claims of this invention.

Claims

1. A nano-ceramic particle-reinforced titanium-aluminum alloy with excellent high-temperature performance, characterized in that, Its preparation method includes the following steps: Step 1: Ti powder, Nb powder and B powder are ball-milled in a molar ratio of 1:1:4-4.5 to obtain the first mixed powder. The ball milling process is as follows: the ball milling time is 6-9 hours, the rotation speed is 40-70 rpm, the particle size range of Ti powder is 10-40 μm, the particle size range of Nb powder is 20-70 μm, and the particle size of B powder is 0.1-1.5 μm. Step 2: Mix the first mixed powder prepared in Step 1 with Ti particles with a particle size of 50-140 μm. 48 Al 48 Cr2Nb2 pre-alloyed powder was ball-milled and mixed at mass ratios of 9-15:1, 4-8:1 and 2-6:1 to obtain second, third and fourth mixed powders, respectively. The ball-milling and mixing process was carried out for 6-10 hours and the ball milling speed was 40-80 rpm. Step 3: Arrange the second, third, and fourth mixed powders obtained in Step 2 in a mass ratio of 1-2:1-2:6-8 on a titanium strip and encapsulate them to obtain a continuous mixed powder titanium column; Step 4: After vacuum induction melting of the TiAl alloy, add the continuously mixed powdered titanium pillars obtained in Step 3. The mass ratio of the continuously mixed powdered titanium pillars to the TiAl alloy is 0.5%–0.8%:

1. After the continuously mixed powdered titanium pillars melt, hold the temperature for 4–10 minutes to generate and uniformly distribute nano-ceramic particles. After casting, a nano-ceramic particle-reinforced titanium-aluminum alloy with excellent high-temperature performance is obtained. The vacuum induction melting process is as follows: under argon protection, heating is started at 3–10 kW, and the power is increased by 5–8 kW every 3–7 minutes until the alloy is completely melted. Then, the temperature is held for 3–7 minutes. The TiAl alloy composition, by mass percentage, includes: Al: 33.0–34.5 wt.%; Cr: 2.3–2.6 wt.%; Nb: 4.7–5.1 wt.%; the remainder is Ti. The microstructure of the high-temperature performance nano-ceramic particle-reinforced titanium-aluminum alloy is lamellar, with an average lamellar size ≤122μm. The internal structure contains uniformly distributed nano-ceramic particles with a particle size of 30-400 nm. At ≥800℃, the yield strength, tensile strength, and fracture strain of the high-temperature performance nano-ceramic particle-reinforced titanium-aluminum alloy are ≥550.6MPa, ≥599.4MPa, and ≥22.8%, respectively.

2. The nano-ceramic particle-reinforced titanium-aluminum alloy with excellent high-temperature performance according to claim 1, characterized in that, As described in step one, the particle size range of Ti powder is 15-30 μm, the particle size range of Nb powder is 25-50 μm, and the particle size of B powder is 0.2-1.0 μm.

3. The nano-ceramic particle-reinforced titanium-aluminum alloy with excellent high-temperature performance according to claim 1, characterized in that, The ball milling mixing process described in step two takes 7-9 hours and the ball milling speed is 50-70 rpm.

4. The nano-ceramic particle-reinforced titanium-aluminum alloy with excellent high-temperature performance according to claim 1, characterized in that, The vacuum induction melting process described in step four is as follows: under argon protection, start heating with a power of 5-8kW, increase the power by 5.5-7kW every 4-6 minutes until the alloy is completely melted, and then hold at that temperature for 4-6 minutes.

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