High-toughness heat-resistant titanium alloy composite material and preparation method thereof

Abstract

The application discloses a high-strength and high-toughness heat-resistant titanium alloy composite material and a preparation method thereof, and relates to the technical field of high-strength and high-toughness structural metal matrix composite materials. The preparation method comprises the following steps: ball-milling and mixing nano-SiC particles and TA15 alloy matrix raw materials, and then performing discharge plasma sintering treatment and multi-pass hot rolling treatment to obtain the high-strength and high-toughness heat-resistant titanium alloy composite material. Through the synergistic effect of vacuum high-energy ball milling, discharge plasma sintering and high-temperature hot rolling, the high-strength and high-toughness heat-resistant titanium alloy composite material is prepared. The synergistic effect of fine-grain strengthening, dislocation strengthening, solid solution strengthening and Orowan strengthening effect makes the prepared composite material exhibit excellent mechanical properties, and effectively solves the problem that the strength and plasticity of the titanium-based composite material cannot be synergistically improved.

Description

Technical Field

[0001] This invention relates to a high-strength, high-toughness, and heat-resistant titanium alloy composite material and its preparation method, belonging to the technical field of high-strength and high-toughness structural metal matrix composite materials. Background Technology

[0002] Titanium alloys, renowned as the "third metal," "space metal," and "marine metal" due to their high specific strength, excellent high and low temperature performance, and strong corrosion resistance, are widely used in aviation, aerospace, marine, military weaponry, automotive, sporting goods, and biomedical fields, holding a particularly important position in the aerospace industry. The amount of high-temperature titanium alloys used has become a key indicator of the level of modern aero-engine technology. However, traditional titanium alloys suffer from rapid strength degradation at high temperatures (strength degradation >30% at 600℃) and insufficient oxidation resistance (oxidation weight gain >2mg / cm³). 2 The performance defects of (·h) make it difficult to meet the high-temperature, high-strength, and high-toughness performance requirements of load-bearing components in spacecraft and key hot-end components in aero-engines. Therefore, the development of a new type of lightweight, high-strength, and high-temperature resistant structural material is of great significance to the development of aerospace vehicles.

[0003] A titanium-based composite material was prepared by introducing a ceramic phase with high elastic modulus and high-temperature oxidation resistance into a titanium alloy matrix using powder metallurgy. This process maintained the matrix density at 4.6 ± 0.2 g / cm³. 3 Under the premise of achieving a 40%-60% increase in modulus and extending its high-temperature service window to the 700-800℃ range, this breakthrough overcomes the traditional thermal barrier effect of titanium alloys and provides a material solution for next-generation aerospace propulsion systems. Existing titanium-based composite materials include Ti-TiB2w, Ti-TiC, Ti-Ti5Si3, and Ti-CNTs / Graphene (carbon nanotubes / graphene added to a titanium matrix). Among them, Si is an indispensable additive element in high-temperature titanium alloys or titanium-based composite materials due to its unique role in anti-oxidation and anti-creep properties. Meanwhile, TiC is often considered an excellent reinforcing phase choice because it has a similar density and coefficient of thermal expansion to the Ti matrix, and its elastic modulus is more than four times that of Ti alloys. However, the weak bonding between the reinforcing phase and the matrix interface, and the tendency of the reinforcing phase to agglomerate at the titanium matrix interface to form large sizes, will cause a sharp decline in mechanical properties, resulting in a significant gap between the strength and plasticity of the prepared composite material and the expected ideal values.

[0004] Currently, mechanical alloying technology can effectively solve the dispersion problem of titanium alloy powder. However, due to the high energy during mechanical alloying, a large number of impurity elements (O and N) are introduced and enriched at the grain boundaries, making the composite material brittle. Furthermore, the mechanical alloying process also generates numerous unstable lattice defects within the powder, leading to stress concentration, inducing crack initiation, and causing premature fracture. Ultimately, this results in a significant deterioration of the material's plasticity and a decrease in high-temperature mechanical properties. Moreover, the TiC reinforcing phase generated through in-situ self-generation reactions easily forms coarse particles at the interface, disrupting the continuity of the matrix and significantly reducing its mechanical properties. These factors ultimately lead to a mismatch between the room-temperature and high-temperature mechanical properties (strength-toughness) of titanium-based composites. Currently, the service temperature of titanium-based composites in high-temperature environments still does not exceed 600℃, making it difficult to guarantee their safety and reliability in high-temperature service environments. Therefore, achieving breakthroughs in preparation techniques to solve the problems of mismatched room-temperature mechanical properties and poor long-term service performance in high-temperature environments is a critical bottleneck that urgently needs to be addressed for the application and development of titanium alloys in the aerospace field. Summary of the Invention

[0005] To address the shortcomings of related technologies, this invention provides a high-strength, high-toughness, and heat-resistant titanium alloy composite material and its preparation method. This invention achieves the preparation of titanium alloys containing TiC and Ti5Si3 reinforcing phases that balance strength and toughness, and solves the problems of mismatched room temperature mechanical properties and poor long-term service performance under high temperature conditions.

[0006] One objective of this invention is to provide a method for preparing a high-strength, high-toughness, and heat-resistant titanium alloy composite material, specifically comprising the following steps: (1) Take nano-SiC particles and TA15 alloy matrix raw materials, mix them to obtain mixed raw materials, and then ball mill and dry the mixed raw materials to obtain SiC-TA15 titanium-based composite powder.

[0007] (2) The SiC-TA15 titanium-based composite powder was subjected to spark plasma sintering to obtain a composite material with internal TiC and Ti5Si3 dual reinforcing phases.

[0008] (3) The composite material with internally generated TiC and Ti5Si3 dual reinforcing phases is subjected to multiple hot rolling processes to obtain a high-strength, high-toughness, and heat-resistant titanium alloy composite material.

[0009] Preferably, the content of nano-SiC particles in the mixed raw materials in step (1) is 0.25%~0.75% by mass percentage, with the remainder being TA15 alloy matrix.

[0010] Preferably, the average particle size of the nano-SiC particles in step (1) is 40 nm; the ball milling mixing conditions are: ball-to-material ratio of (5:1~10:1), ball milling speed of 150~300 rpm, and ball milling for 5~10 h under a protective atmosphere.

[0011] More preferably, in step (1), anhydrous ethanol is added for wet milling during the ball milling process; the protective atmosphere is argon atmosphere; and the ball milling process is subjected to three vacuuming and argon filling treatments.

[0012] More preferably, the drying conditions in step (1) are: drying at 45°C for 6 hours.

[0013] Preferably, the conditions for the discharge plasma sintering treatment in step (2) are: discharge plasma sintering for 5 to 30 minutes at a pressure of 20 to 40 MPa and a temperature of 900 to 1200 °C.

[0014] Preferably, the conditions for the multi-pass hot rolling process in step (3) are: after holding at 900~1100℃ for 5~30min, multi-pass hot rolling is performed, with a single rolling amount of 10% and a total rolling amount of 20~80%.

[0015] Another objective of this invention is to provide a high-strength, high-toughness, and heat-resistant titanium alloy composite material prepared using the method of this invention.

[0016] Mechanism of the invention: This invention achieves in-situ generation and size optimization of dual-reinforcement phases through the synergistic effect of vacuum high-energy ball milling, spark plasma sintering, and high-temperature hot rolling. The preparation flow chart of this invention is shown below. Figure 1 As shown in (a), vacuum high-energy ball milling combined with multiple vacuuming and argon purging effectively isolates impurities while ensuring uniform dispersion of SiC particles, providing a clean mixed powder for subsequent reactions. The synergistic effect of vacuum high-energy ball milling, spark plasma sintering, and high-temperature hot rolling in this invention not only suppresses grain coarsening but also generates TiC and Ti5Si3 dual reinforcing phases through in-situ reactions, ensuring strong interfacial bonding between the reinforcing phase and the matrix. At the same time, by utilizing the characteristic of increased solid solubility of C in the upper part of the α phase region, a large number of defects are introduced, which not only promotes the fracture and decomposition of TiC aggregated at the phase boundary but also provides a rapid diffusion channel for the decomposed C elements. Ultimately, the coarse TiC at the interface is refined to the nanoscale or even eliminated, while Ti5Si3 is kept uniformly distributed, realizing the preparation of a titanium-based composite material with uniform reinforcing phase distribution and high room temperature strength, high elastic modulus, and excellent high-temperature strength.

[0017] The beneficial effects of this invention are: (1) In the high strength, toughness and heat resistance titanium alloy composite material of the present invention, the TiC and Ti5Si3 reinforcing phases are distributed in the TA15 alloy matrix, wherein the TiC reinforcing phase is located at the phase interface of the titanium alloy matrix, and the Ti5Si3 is distributed in the β phase in the titanium alloy matrix.

[0018] (2) The composite material of the present invention achieves uniform mixing of nano-SiC powder and TA15 powder through the synergistic effect of high-energy ball milling, spark plasma (SPS) rapid reaction sintering and multi-pass hot rolling process, which solves the technical problem of brittleness caused by the introduction of impurities in the traditional mechanical alloying method for preparing titanium-based composite materials; the rapid in-situ reaction of raw materials improves the interfacial bonding force between the reinforcing phase and the matrix; at the same time, it realizes the dispersion distribution of TiC and Ti5Si3 reinforcing phases in Ti alloy matrix; and makes TiC and Ti5Si3 finely dispersed, thus preparing a high-strength, tough and heat-resistant titanium alloy composite material.

[0019] (3) The high-strength, high-toughness, heat-resistant titanium alloy composite material of the present invention exhibits excellent mechanical properties due to the synergistic effect of fine grain strengthening, dislocation strengthening, solid solution strengthening and Orowan strengthening effect. This significantly improves the tensile strength and elongation at break of the composite material, effectively solving the dilemma that the strength and plasticity of existing titanium-based composite materials cannot be improved in a synergistic way. At the same time, the method effectively reduces the requirements for equipment and energy consumption, making it more suitable for large-scale industrial production and high-end applications. Attached Figure Description

[0020] Figure 1 This is a flowchart of the preparation process and mechanical property testing diagram of the high-strength, tough, and heat-resistant titanium alloy composite material of the present invention; Figure 1 (a) is the preparation process flowchart. Figure 1 (b) shows the mechanical performance test diagram. Detailed Implementation

[0021] To better illustrate the purpose, technical solution, and advantages of this invention, the invention will be further described below with reference to specific embodiments. In the embodiments and comparative examples of this invention, unless otherwise specified, all chemical reagents used in the experiments were commercially available analytical grade. The TA15 alloy matrix raw material composition used in the embodiments and comparative examples of this invention, by mass percentage, includes: 6.5% Al, 2% Zr, 1% Mo, 1% V, with the balance being Ti; the alloy matrix of this invention can also be a TA15 alloy matrix whose composition conforms to the GB / T3620.1-2016 standard and is suitable for use in aerospace equipment.

[0022] Example 1 A method for preparing a high-strength, high-toughness, and heat-resistant titanium alloy composite material specifically includes the following steps: (1) Take nano-SiC particles (average particle size of 40nm) and TA15 alloy matrix raw materials, wherein the content of nano-SiC particles is 0.5% by mass percentage and the remainder is TA15 alloy matrix. Then, vacuum high-energy ball milling is performed at a ball-to-material ratio of 5:1, a ball milling speed of 300rpm, and an argon atmosphere for 10h. During the ball milling process, vacuum purging and argon filling are performed three times and anhydrous ethanol is added for wet milling (anhydrous ethanol is added to the raw material at a solid-liquid ratio of 30g:20mL for ball milling). Then, dry at 45℃ for 6h to obtain SiC-TA15 titanium-based composite powder.

[0023] (2) The SiC-TA15 titanium-based composite powder was subjected to discharge plasma sintering at a sintering temperature of 1200℃ and a pressure of 40MPa for 8 minutes to obtain a composite material with internal TiC and Ti5Si3 dual reinforcing phases.

[0024] (3) The composite material with internally generated TiC and Ti5Si3 dual reinforcing phases is placed in a stainless steel 304 sheath to avoid its oxidation and embrittlement at high temperature. After holding at 900℃ for 30 min, it is subjected to multiple hot rolling processes with a single rolling amount of 10% and a total rolling amount of 60%. Then, it is water quenched to room temperature to obtain a high-strength, tough and heat-resistant titanium alloy composite material.

[0025] The composite material prepared in this embodiment was cut into dog bone shapes and subjected to tensile tests at room temperature and high temperature to evaluate its mechanical properties. The measured mechanical properties of the alloy are as follows: the ultimate tensile strength is as high as 1250 MPa (see...). Figure 1 In (b), the elongation at break is 7%.

[0026] Example 2 A method for preparing a high-strength, high-toughness, and heat-resistant titanium alloy composite material specifically includes the following steps: (1) Take nano-SiC particles (average particle size of 40nm) and TA15 alloy matrix raw materials, wherein the content of nano-SiC particles is 0.5% by mass percentage and the remainder is TA15 alloy matrix. Then, vacuum high-energy ball milling is performed at a ball-to-material ratio of 5:1, a ball milling speed of 300rpm, and an argon atmosphere for 10h. During the ball milling process, vacuum purging and argon filling are performed three times and anhydrous ethanol is added for wet milling (anhydrous ethanol is added to the raw material at a solid-liquid ratio of 30g:20mL for ball milling). Then, dry at 45℃ for 6h to obtain SiC-TA15 titanium-based composite powder.

[0027] (2) The SiC-TA15 titanium-based composite powder was subjected to discharge plasma sintering at a sintering temperature of 1200℃ and a pressure of 40MPa for 8 minutes to obtain a composite material with internal TiC and Ti5Si3 dual reinforcing phases.

[0028] (3) The composite material with internally generated TiC and Ti5Si3 dual reinforcing phases is placed in a stainless steel 304 sheath to avoid its oxidation and embrittlement at high temperature. After holding at 1100℃ for 30 min, it is subjected to multiple hot rolling processes with a single rolling amount of 10% and a total rolling amount of 60%. Then, it is water quenched to room temperature to obtain a high-strength, tough, and heat-resistant titanium alloy composite material.

[0029] The composite material prepared in this embodiment was cut into dog bone shapes and subjected to tensile tests at room temperature and high temperature to evaluate its mechanical properties. The measured mechanical properties of the alloy are as follows: the ultimate tensile strength is as high as 1340 MPa (see...). Figure 1 In (b), the elongation at break is 13%.

[0030] Example 3 A method for preparing a high-strength, high-toughness, and heat-resistant titanium alloy composite material specifically includes the following steps: (1) Take nano-SiC particles (average particle size of 40nm) and TA15 alloy matrix raw materials, wherein the content of nano-SiC particles is 0.5% by mass percentage and the remainder is TA15 alloy matrix. Then, vacuum high-energy ball milling is performed at a ball-to-material ratio of 5:1, a ball milling speed of 300rpm, and an argon atmosphere for 10h. During the ball milling process, vacuum purging and argon filling are performed three times and anhydrous ethanol is added for wet milling (anhydrous ethanol is added to the raw material at a solid-liquid ratio of 30g:20mL for ball milling). Then, dry at 45℃ for 6h to obtain SiC-TA15 titanium-based composite powder.

[0031] (2) The SiC-TA15 titanium-based composite powder was subjected to discharge plasma sintering at a sintering temperature of 1200℃ and a pressure of 40MPa for 8 minutes to obtain a composite material with internal TiC and Ti5Si3 dual reinforcing phases.

[0032] (3) The composite material with internally generated TiC and Ti5Si3 dual reinforcing phases is placed in a stainless steel 304 sheath to avoid its oxidation and embrittlement at high temperature. After holding at 1000℃ for 30 min, it is subjected to multiple hot rolling processes with a single rolling amount of 10% and a total rolling amount of 60%. Then, it is water quenched to room temperature to obtain a high-strength, tough, and heat-resistant titanium alloy composite material.

[0033] The composite material prepared in this embodiment was cut into dog bone shapes and subjected to tensile tests at room temperature and high temperature to evaluate its mechanical properties. The measured mechanical properties of the alloy are as follows: the ultimate tensile strength is as high as 1180 MPa (see...). Figure 1 In (b), the elongation at break is 9%.

[0034] Example 4 A method for preparing a high-strength, high-toughness, and heat-resistant titanium alloy composite material specifically includes the following steps: (1) Take nano-SiC particles (average particle size of 40nm) and TA15 alloy matrix raw materials, wherein the content of nano-SiC particles is 0.75% by mass percentage and the remainder is TA15 alloy matrix. Then, vacuum high-energy ball milling is performed at a ball-to-material ratio of 5:1, a ball milling speed of 300rpm, and an argon atmosphere for 10h. During the ball milling process, vacuum purging and argon filling are performed three times and anhydrous ethanol is added for wet milling (anhydrous ethanol is added to the raw material at a solid-liquid ratio of 30g:20mL for ball milling). Then, dry at 45℃ for 6h to obtain SiC-TA15 titanium-based composite powder.

[0035] (2) The SiC-TA15 titanium-based composite powder was subjected to discharge plasma sintering at a sintering temperature of 1200℃ and a pressure of 40MPa for 8 minutes to obtain a composite material with internal TiC and Ti5Si3 dual reinforcing phases.

[0036] (3) The composite material with internally generated TiC and Ti5Si3 dual reinforcing phases is placed in a stainless steel 304 sheath to avoid its oxidation and embrittlement at high temperature. After holding at 900℃ for 30 min, it is subjected to multiple hot rolling processes with a single rolling amount of 10% and a total rolling amount of 60%. Then, it is water quenched to room temperature to obtain a high-strength, tough and heat-resistant titanium alloy composite material.

[0037] The composite material prepared in this embodiment was cut into dog bone shapes and subjected to tensile tests at room temperature and high temperature to evaluate its mechanical properties. The measured mechanical properties of the alloy are as follows: the ultimate tensile strength is as high as 1380 MPa and the elongation at break is 8%.

[0038] Example 5 A method for preparing a high-strength, high-toughness, and heat-resistant titanium alloy composite material specifically includes the following steps: (1) Take nano-SiC particles (average particle size of 40nm) and TA15 alloy matrix raw materials, wherein the content of nano-SiC particles is 0.75% by mass percentage and the remainder is TA15 alloy matrix. Then, vacuum high-energy ball milling is performed at a ball-to-material ratio of 5:1, a ball milling speed of 200rpm, and an argon atmosphere for 5h. During the ball milling process, vacuum purging and argon filling are performed three times and anhydrous ethanol is added for wet milling (anhydrous ethanol is added to the raw material at a solid-liquid ratio of 30g:20mL for ball milling). Then, dry at 45℃ for 6h to obtain SiC-TA15 titanium-based composite powder.

[0039] (2) The SiC-TA15 titanium-based composite powder was subjected to discharge plasma sintering at a sintering temperature of 1200℃ and a pressure of 40MPa for 5min to obtain a composite material with internal TiC and Ti5Si3 dual reinforcing phases.

[0040] (3) The composite material with internally generated TiC and Ti5Si3 dual reinforcing phases is placed in a stainless steel 304 sheath to avoid its oxidation and embrittlement at high temperature. After holding at 1100℃ for 5 minutes, it is subjected to multiple hot rolling processes with a single rolling amount of 10% and a total rolling amount of 20%. Then, it is water quenched to room temperature to obtain a high-strength, tough, and heat-resistant titanium alloy composite material.

[0041] The composite material prepared in this embodiment was cut into dog bone shapes and subjected to tensile tests at room temperature and high temperature to evaluate its mechanical properties. The measured mechanical properties of the alloy are as follows: the ultimate tensile strength is as high as 1400 MPa and the elongation at break is 6%.

[0042] Example 6 A method for preparing a high-strength, high-toughness, and heat-resistant titanium alloy composite material specifically includes the following steps: (1) Take nano-SiC particles (average particle size of 40nm) and TA15 alloy matrix raw materials, wherein the content of nano-SiC particles is 0.25% by mass percentage and the remainder is TA15 alloy matrix. Then, vacuum high-energy ball milling is performed at a ball-to-material ratio of 10:1, a ball milling speed of 150rpm, and an argon atmosphere for 8h. During the ball milling process, vacuum purging and argon filling are performed three times and anhydrous ethanol is added for wet milling (anhydrous ethanol is added to the raw material at a solid-liquid ratio of 30g:20mL for ball milling). Then, dry at 45℃ for 6h to obtain SiC-TA15 titanium-based composite powder.

[0043] (2) The SiC-TA15 titanium-based composite powder was subjected to discharge plasma sintering at a sintering temperature of 900℃ and a pressure of 30MPa for 8 minutes to obtain a composite material with internal TiC and Ti5Si3 dual reinforcing phases.

[0044] (3) The composite material with internally generated TiC and Ti5Si3 dual reinforcing phases is placed in a stainless steel 304 sheath to avoid its oxidation and embrittlement at high temperature. After holding at 1000℃ for 20 minutes, it is subjected to multiple hot rolling processes with a single rolling amount of 10% and a total rolling amount of 80%. Then, it is water quenched to room temperature to obtain a high-strength, tough, and heat-resistant titanium alloy composite material.

[0045] The composite material prepared in this embodiment was cut into dog bone shapes and subjected to tensile tests at room temperature and high temperature to evaluate its mechanical properties. The measured mechanical properties of the alloy are as follows: the ultimate tensile strength is as high as 1180 MPa and the elongation at break is 5%.

[0046] Example 7 A method for preparing a high-strength, high-toughness, and heat-resistant titanium alloy composite material specifically includes the following steps: (1) Take nano-SiC particles (average particle size of 40nm) and TA15 alloy matrix raw materials, wherein the content of nano-SiC particles is 0.75% by mass percentage and the remainder is TA15 alloy matrix. Then, vacuum high-energy ball milling is performed at a ball-to-material ratio of 7:1, a ball milling speed of 300rpm, and an argon atmosphere for 10h. During the ball milling process, vacuum purging and argon filling are performed three times and anhydrous ethanol is added for wet milling (anhydrous ethanol is added to the raw material at a solid-liquid ratio of 30g:20mL for ball milling). After drying at 45℃ for 6h, SiC-TA15 titanium-based composite powder is obtained.

[0047] (2) The SiC-TA15 titanium-based composite powder was subjected to discharge plasma sintering at a sintering temperature of 1000℃ and a pressure of 20MPa for 8 minutes to obtain a composite material with internal TiC and Ti5Si3 dual reinforcing phases.

[0048] (3) The composite material with internally generated TiC and Ti5Si3 dual reinforcing phases is placed in a stainless steel 304 sheath to avoid its oxidation and embrittlement at high temperature. After holding at 1100℃ for 30 min, it is subjected to multiple hot rolling processes with a single rolling amount of 10% and a total rolling amount of 60%. Then, it is water quenched to room temperature to obtain a high-strength, tough, and heat-resistant titanium alloy composite material.

[0049] The composite material prepared in this embodiment was cut into dog bone shapes and subjected to tensile tests at room temperature and high temperature to evaluate its mechanical properties. The measured mechanical properties of the alloy are as follows: the ultimate tensile strength is as high as 1150 MPa and the elongation at break is 5%.

[0050] This invention utilizes the synergistic effects of high-energy ball milling, rapid reaction sintering with spark plasma, and multi-pass hot rolling processes to achieve uniform mixing of nano-SiC powder and TA15 powder, thereby enhancing the interfacial bonding between the reinforcing phase and the matrix. Simultaneously, it achieves dispersed distribution of TiC and Ti5Si3 reinforcing phases within the Ti alloy matrix, refining and dispersing TiC and Ti5Si3 to prepare a high-strength, high-toughness, and heat-resistant titanium alloy composite material. The synergistic effects of grain refinement, dislocation strengthening, solid solution strengthening, and Orowan strengthening in this high-strength, high-toughness, and heat-resistant titanium alloy composite material result in excellent mechanical properties, significantly improving the tensile strength and elongation at break. This effectively solves the dilemma of existing titanium-based composite materials where strength and plasticity cannot be simultaneously improved. Furthermore, this method effectively reduces equipment and energy consumption requirements, making it more suitable for large-scale industrial production and high-end applications. In the high-strength, high-toughness, and heat-resistant titanium alloy composite material prepared by the method of the present invention, the volume percentage content of TiC is 0%~32.7% (excluding 0) and the volume percentage content of Ti5Si3 is 67.3%~100%, based on the total volume of the reinforcing phase as 100%.

[0051] Comparative Example 1 A method for preparing TA15 titanium alloy composite material specifically includes the following steps: (1) Take TA15 alloy matrix raw material, and then use vacuum high-energy ball milling at a ball-to-material ratio of 5:1, a ball milling speed of 300 rpm, and an argon atmosphere for 10 h. The ball milling process is subjected to three vacuum purging and argon filling treatments and anhydrous ethanol is added for wet milling (anhydrous ethanol is added to the raw material at a solid-liquid ratio of 30 g: 20 mL for ball milling). Then dry at 45 °C for 6 h to obtain TA15 titanium-based powder.

[0052] (2) TA15 titanium-based powder was subjected to discharge plasma sintering at a sintering temperature of 1200℃ and a pressure of 40MPa for 8 minutes to obtain TA15 titanium alloy composite material.

[0053] The composite material prepared in this comparative example was cut into dog bone shapes and subjected to tensile tests at room temperature and high temperature to evaluate its mechanical properties. The measured mechanical properties of the alloy are as follows: ultimate tensile strength is 1050 MPa (see...). Figure 1 In (b), the elongation at break was 5%. Since no nano-SiC particles were added in this comparative example, the in-situ reaction to generate the reinforcing phase was not achieved during sintering, and no subsequent thermal processing was carried out, resulting in insufficient mechanical properties.

[0054] Comparative Example 2 A method for preparing a high-strength, high-toughness, and heat-resistant titanium alloy composite material specifically includes the following steps: (1) Take nano-SiC particles (average particle size of 40nm) and TA15 alloy matrix raw materials, wherein the content of nano-SiC particles is 0.5% by mass percentage and the remainder is TA15 alloy matrix. Then, vacuum high-energy ball milling is performed at a ball-to-material ratio of 5:1, a ball milling speed of 300rpm, and an argon atmosphere for 10h. During the ball milling process, vacuum purging and argon filling are performed three times and anhydrous ethanol is added for wet milling (anhydrous ethanol is added to the raw material at a solid-liquid ratio of 30g:20mL for ball milling). Then, dry at 45℃ for 6h to obtain SiC-TA15 titanium-based composite powder.

[0055] (2) The SiC-TA15 titanium-based composite powder was hot-pressed and sintered at a sintering temperature of 1200℃ and a pressure of 40MPa for 1h to obtain a composite material with internal TiC and Ti5Si3 dual reinforcing phases.

[0056] (3) The composite material with internally generated TiC and Ti5Si3 dual reinforcing phases is placed in a stainless steel 304 sheath to avoid its oxidation and embrittlement at high temperature. After holding at 900℃ for 30 min, it is subjected to multiple hot rolling processes with a single rolling amount of 10% and a total rolling amount of 60%. Then, it is water quenched to room temperature to obtain a high-strength, tough and heat-resistant titanium alloy composite material.

[0057] The composite material prepared in this comparative example was cut into dog bone shapes and subjected to tensile tests at room temperature and high temperature to evaluate its mechanical properties. The measured mechanical properties of the alloy are as follows: ultimate tensile strength is 1050 MPa, and elongation at break is 4%. This is because the comparative example uses hot pressing sintering to generate the reinforcing phase, resulting in severe interfacial reactions in the TA15 matrix, making the grains more prone to coarsening. Furthermore, the hot pressing sintering process has a slow heating rate and long holding time, making it difficult to improve the density.

[0058] Comparative Example 3 A method for preparing a high-strength, high-toughness, and heat-resistant titanium alloy composite material specifically includes the following steps: (1) Take nano-SiC particles (average particle size of 40nm) and TA15 alloy matrix raw materials, wherein the content of nano-SiC particles is 0.5% by mass percentage and the remainder is TA15 alloy matrix. Then, vacuum high-energy ball milling is performed at a ball-to-material ratio of 5:1, a ball milling speed of 300rpm, and an argon atmosphere for 10h. During the ball milling process, vacuum purging and argon filling are performed three times and anhydrous ethanol is added for wet milling (anhydrous ethanol is added to the raw material at a solid-liquid ratio of 30g:20mL for ball milling). Then, dry at 45℃ for 6h to obtain SiC-TA15 titanium-based composite powder.

[0059] (2) The SiC-TA15 titanium-based composite powder was subjected to discharge plasma sintering at a sintering temperature of 1200℃ and a pressure of 40MPa for 8 minutes to obtain a composite material with internal TiC and Ti5Si3 dual reinforcing phases.

[0060] (3) The composite material with internally generated TiC and Ti5Si3 dual reinforcing phases is subjected to cold rolling treatment, and the single-pass rolling amount is controlled to be 5% and the total rolling amount is 30% to obtain a high-strength, tough and heat-resistant titanium alloy composite material.

[0061] The composite material prepared in this comparative example was cut into dog bone shapes and subjected to tensile tests at room temperature and high temperature to evaluate its mechanical properties. The measured mechanical properties of the alloy are as follows: ultimate tensile strength is 1100 MPa, and elongation at break is 4%. This comparative example uses a cold rolling process to process the composite material with internal TiC and Ti5Si3 dual reinforcing phases. During the cold rolling process, the deformation resistance is large, the work hardening is severe, the residual stress is high, and it is difficult to achieve dynamic recrystallization, which makes it difficult to improve its plasticity.

[0062] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A method for preparing a high-strength, high-toughness, and heat-resistant titanium alloy composite material, characterized in that, Specifically, the following steps are included: (1) Take nano-SiC particles and TA15 alloy matrix raw materials, mix them to obtain mixed raw materials, and then ball mill and dry the mixed raw materials to obtain SiC-TA15 titanium-based composite powder; (2) The SiC-TA15 titanium-based composite powder was subjected to spark plasma sintering to obtain a composite material with internal TiC and Ti5Si3 dual reinforcing phases; (3) The composite material with internally generated TiC and Ti5Si3 dual reinforcing phases is subjected to multiple hot rolling processes to obtain a high-strength, high-toughness, and heat-resistant titanium alloy composite material.

2. The method for preparing the high-strength, high-toughness, and heat-resistant titanium alloy composite material according to claim 1, characterized in that, The content of nano-SiC particles in the mixed raw materials in step (1) is 0.25%~0.75% by mass percentage, with the remainder being TA15 alloy matrix.

3. The method for preparing the high-strength, high-toughness, and heat-resistant titanium alloy composite material according to claim 1, characterized in that, The average particle size of the nano-SiC particles in step (1) is 40 nm; the ball milling mixing conditions are: ball milling for 5 to 10 hours at a ball-to-material ratio of (5:1 to 10:1), a ball milling speed of 150 to 300 rpm, and a protective atmosphere.

4. The method for preparing the high-strength, high-toughness, and heat-resistant titanium alloy composite material according to claim 1, characterized in that, The conditions for the discharge plasma sintering treatment in step (2) are: discharge plasma sintering for 5 to 30 minutes at a pressure of 20 to 40 MPa and a temperature of 900 to 1200 °C.

5. The method for preparing the high-strength, high-toughness, and heat-resistant titanium alloy composite material according to claim 1, characterized in that, The conditions for the multi-pass hot rolling process in step (3) are as follows: after holding at 900~1100℃ for 5~30min, multi-pass hot rolling is carried out, with a single rolling amount of 10% and a total rolling amount of 20~80%.

6. The high-strength, high-toughness, and heat-resistant titanium alloy composite material prepared by the method according to any one of claims 1 to 5.

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