Titanium-based composite material with adjustable and controllable reinforced phase structure and preparation method of titanium-based composite material

Abstract

The invention discloses a titanium-based composite material with an adjustable and controllable reinforced phase structure and a preparation method of the titanium-based composite material. The preparation method comprises the steps that matrix powder and reinforced phase raw materials are mixed, ball-milled and dried to obtain mixed powder; printing the mixed powder on a titanium alloy substrate through additive manufacturing to obtain a titanium-based composite material; wherein when the granularity of the reinforcing phase raw material is in a nanometer level and the mass percent of the reinforcing phase raw material in the mixed powder is 0.01%-2%, along with the gradient decrease of the mass percent of the reinforcing phase raw material, the structure of the reinforcing phase in the obtained titanium-based composite material is converted into a net shape, a net and dispersion coexistence shape and a dispersion shape. According to the preparation method, the titanium-based composite material with proper obdurability can be obtained by regulating and controlling the size and the content of the reinforced phase raw materials.

Description

Technical Field

[0001] The present invention belongs to the technical field of additive manufacturing of metal-based composite materials, and in particular relates to a titanium-based composite material with an adjustable and controllable reinforcement phase structure and a preparation method thereof. Background Art

[0002] Titanium-based composites have broad application prospects in high-end equipment such as aerospace due to their potential high strength, high toughness and heat resistance. Additive manufacturing technology is becoming an important way to achieve functional optimization design and lightweight manufacturing of high-end aerospace products, and has been widely and deeply studied in the regulation of the microstructure and properties of titanium alloys and titanium-based composites. Therefore, the mechanical properties and application potential of titanium-based composites regulated by additive manufacturing will be even greater.

[0003] For traditional titanium-based composites, the introduction of reinforcement phases sacrifices plasticity and fracture toughness, resulting in obvious brittle characteristics, which is sometimes fatal for engineering applications. According to relevant research results, the uniform distribution or relatively dispersed distribution state of the reinforcement phase regulated by traditional means cannot fully exert the performance of the matrix and reinforcement phase. In recent years, in order to overcome the problem of incompatibility between strength and plasticity of traditional titanium-based composites, the design ideas and preparation methods of non-uniform distribution of reinforcement phases have gradually developed. By precisely controlling the spatial distribution of the reinforcement phase, a uniform and regular reinforcement phase network structure at the mesoscopic scale is obtained, that is, a hard-encapsulated soft microstructure is formed, the reinforcement phase is enriched to form a hard network wall to contribute to the strength of the material, and the matrix inside the network provides plastic deformation ability and loads, giving full play to the synergistic effect of the matrix and reinforcement phase. Therefore, the network distribution of the reinforcement phase has the potential to solve the contradiction between strength and plasticity.

[0004] Powder metallurgy (PM) is one of the most commonly used methods. Domestic and foreign researchers have successfully prepared titanium-based composites with a spatial network structure distribution of the reinforcement phase using this method. Specifically, the matrix is ​​metallurgically bonded by hot pressing sintering, plasma sintering and other methods. In this process, the elements added to the surface of the powder react with the matrix to form a reinforcement phase, and the powder forms a matrix inside the network structure to construct a spatial network structure. The powder system and the reinforcement phase system can be replaced according to actual application requirements, which has certain advantages. However, the size of the network structure is still relatively large, and the matrix in the network cannot coordinate plastic deformation well, so the uniform deformation capacity and tensile strength of the titanium-based composite cannot be significantly improved. In addition, the reported network structure titanium-based composites are prone to failure modes along the network wall, which reduces the fracture toughness of the material. This is because the reinforcement phase is not self-generated by in-situ reaction under complete remelting under the conditions of powder metallurgy process, and there are interface defects.

[0005] Chinese invention patent CN 101333607 B discloses a preparation method of a TiBw / Ti alloy matrix composite material. This invention is based on powder metallurgy to prepare a Ti alloy matrix composite material with a reticular structure of TiBw. Compared with the matrix alloy, the strength is improved, but the elongation is relatively low, and the contradiction between strength and plasticity is obvious.

[0006] Chinese invention patent CN 202310051434.3 discloses a preparation method of a core-shell structured titanium-based composite powder and a reticular structured titanium-based composite material. This invention obtains a reticular structure of the reinforcing phase based on powder metallurgy, but the size of the reticular structure of the reinforcing phase is limited by the powder size and cannot be adjusted and controlled during the preparation process.

[0007] Therefore, there is no report on the preparation of a titanium-based composite material with an adjustable and controllable reinforcing phase structure based on laser melting deposition technology. Compared with traditional methods, the parameter adjustment range of the additive manufacturing process is wider, and the process of adjusting the tissue properties is more controllable. Therefore, by optimizing the printing parameters and design path strategies, the reinforcing phase structure (morphology and distribution) can be precisely adjusted, and at the same time, the non-uniform distribution of the matrix phase can be adjusted, so as to realize the integrated regulation of the reinforcing phase structure-mechanical properties of the titanium-based composite material. Among them, regulating the reticular distribution and micro-dispersion distribution of the reinforcing phase based on additive manufacturing technology is expected to further improve the comprehensive mechanical properties of the titanium-based composite material, which is of great significance for the development of high-strength, tough and heat-resistant titanium-based composite materials, and will also provide a method reference for the research of other high-performance metal matrix composite materials by additive manufacturing. Summary of the Invention

[0008] The present invention provides a preparation method of a titanium-based composite material with an adjustable and controllable reinforcing phase structure. This preparation method can obtain a titanium-based composite material with appropriate strength and toughness by regulating the size and content of the reinforcing phase raw materials.

[0009] The present invention provides a preparation method of a titanium-based composite material with an adjustable and controllable reinforcing phase structure, including: Mixing, ball milling and drying the matrix powder and the reinforcing phase raw materials to obtain a mixed powder; Printing the mixed powder onto a titanium alloy substrate by additive manufacturing to obtain a titanium-based composite material; Among them, when the particle size of the reinforcing phase raw materials is at the nanometer level and the mass percentage of the reinforcing phase raw materials in the mixed powder is 0.01% - 2%, as the mass percentage of the reinforcing phase raw materials decreases, the structural transformation process of the reinforcing phase in the obtained titanium-based composite material is reticular → coexistence of reticular and dispersed → dispersed.

[0010] During the laser melting deposition process of the present invention, the in-situ self-generated reinforcing phase has a good combination with the matrix, and the fine reticular structure can coordinate the plastic deformation of the reticular structure and the matrix, solving the contradiction between strength and plasticity and breaking through the limitations of traditional means for regulating the mechanical properties of titanium matrix composites.

[0011] By changing the parameters of the original additive of the reinforcing phase, the size of the reticular structure can be adjusted and controlled. Reticular structures of different sizes exhibit different strengths and plasticities, enabling the customization of the mechanical properties of titanium matrix composites.

[0012] The titanium matrix composite with a dispersed distribution of the reinforcing phase prepared based on the laser melting deposition technology breaks through the problem of poor plasticity of the titanium matrix composite with a dispersed distribution of the reinforcing phase prepared by traditional means. After additive manufacturing, subsequent heat treatment is not required, realizing the integrated manufacturing of structure - microstructure - function of the titanium matrix composite and meeting the application requirements of complex structural parts in the high-end equipment field.

[0013] Preferably, when the particle size of the reinforcing phase raw material is at the nanometer level and the mass percentage of the reinforcing phase raw material is 1% - 2%, the structure of the reinforcing phase in the titanium matrix composite is a reticular structure, the tensile strength is 1150 MPa - 1300 MPa, and the elongation at break is 3% - 8%; When the particle size of the reinforcing phase raw material is at the nanometer level and the mass percentage of the reinforcing phase raw material is 0.1% - 0.5% (excluding the endpoint 0.1%), the structure of the reinforcing phase in the titanium matrix composite is a mixed structure with coexisting reticular and dispersed structures, the tensile strength is 1200 MPa - 1350 MPa, and the elongation at break is 6% - 11%; When the particle size of the reinforcing phase raw material is at the nanometer level and the mass percentage of the reinforcing phase raw material is less than or equal to 0.1% and greater than 0.01%, the structure of the reinforcing phase in the titanium matrix composite is a dispersed structure, the tensile strength is 1000 MPa - 1200 MPa, and the elongation at break is 8% - 12%.

[0014] During the laser melting deposition forming process, at the same content, the nano-particles are driven by the heat flow to aggregate at the grain boundaries or the boundaries of the molten pool, forming a reticular structure distribution, while the rest of the region remains dispersed. This mixed mode is beneficial to the coordination of strength and plasticity. The micron-sized particles have a large size and low surface energy, and their diffusion is inhibited due to density differences or the rapid cooling of the molten pool, resulting in the aggregation of the reinforcing phase mainly along the grain boundaries or the boundaries of the molten pool, forming a reticular structure and making it difficult to achieve a dispersed distribution.

[0015] Further preferably, the reinforcing phase raw material is B4C, and the matrix powder is TC4 (Ti6Al4V). During the laser melting process, the reinforcing phase raw material B4C reacts in-situ with the matrix Ti to generate TiB and TiC double reinforcing phases, i.e., Ti + B4C → TiB + TiC. TiB usually appears as whiskers or short rods, and the semi-coherent interface formed with the matrix provides load transfer strengthening, and also plays a role in hindering dislocation movement and coordinating the deformation of the matrix phase; TiC exists in the form of nanoparticles, hindering dislocation movement, and part of the C is dissolved in the matrix phase, playing a role in solution strengthening. The synergistic strengthening of such multi-scale and multi-morphology reinforcing phases significantly improves the strength and toughness of the material. In addition, both TiB and TiC can serve as heterogeneous nucleation sites to refine the grain size of the matrix phase.

[0016] Further preferably, the particle size of the reinforcing phase raw material is 1 nm - 100 nm. Nanoparticles have a high specific surface area and surface energy, can serve as heterogeneous nucleation sites, significantly increase the nucleation rate, and refine the grain size of the matrix phase. The high specific surface area can also better absorb laser energy, promote uniform diffusion and sufficient reaction after the raw materials are melted, so that the morphology of the matrix phase is more uniform.

[0017] Preferably, when the particle size of the reinforcing phase raw material is in the micron level and the mass percentage content of the reinforcing phase raw material in the mixed powder is 0.1% - 2.5%, the structure of the reinforcing phase in the titanium matrix composite is a network structure; When the particle size of the reinforcing phase raw material is in the micron level and the mass percentage of the reinforcing phase raw material in the mixed powder is less than 0.1%, the structure of the reinforcing phase in the titanium matrix composite is a dispersed distribution; When the particle size of the reinforcing phase raw material is in the micron level and the mass percentage of the reinforcing phase raw material in the mixed powder is greater than 2.5%, the structure of the reinforcing phase in the titanium matrix composite is a high-density dispersed distribution or a local aggregation distribution.

[0018] When the mass percentage of the reinforcing phase raw material in the mixed powder is relatively low, since the content of the formed reinforcing phase in the structure is relatively low, a network structure cannot be obtained. When the mass percentage of the reinforcing phase raw material is relatively high, since too many formed reinforcing phases are prone to aggregation, a high-density dispersed distribution or a local aggregation distribution is formed.

[0019] Further preferably, the particle size of the reinforcing phase raw material is 1 μm - 10 μm. During the laser melting process, the reinforcing phase raw material with this particle size reacts more fully, has an obvious refining effect on the matrix phase, and inhibits the formation of thick columnar crystals in the deposition direction and promotes the formation of equiaxed crystals. If the particle size is larger, the reinforcing phase raw material is not easily completely melted, and uneven flow leads to agglomeration, or insufficient reaction leads to local stress concentration.

[0020] Further preferably, the reinforcing phase raw material is B4C, the matrix powder is TC4, the mass percentage of the reinforcing phase raw material in the mixed powder is 0.5% - 2.5%, and when the mass percentage of the reinforcing phase raw material in the mixed powder increases, the size of the network structure decreases.

[0021] Preferably, the reinforcing phase raw material is B4C, TiB2, La2O3 or LaB6, and the matrix powder is TC4, TA15, TA1 or TC18.

[0022] The reinforcing phase raw material selected in the present invention is a compound or elemental particle that can chemically react with Ti element to form a ceramic reinforcing phase.

[0023] Preferably, the particle size of the matrix powder is 50 μm - 150 μm.

[0024] Preferably, the process of ball milling is as follows: Pour the weighed mixed powder into a ball milling tank, seal the ball milling tank and evacuate it, mix the matrix powder and the reinforcing phase raw material in proportion in a planetary ball mill, rotation speed: 100 r / min - 300 r / min, time: 3 h - 6 h, rotation strategy: change the rotation direction of the ball mill every 30 min, steel ball size: 3 mm - 5 mm, and pause for 5 min - 15 min, ball-to-powder ratio: 3:1 - 5:1.

[0025] Preferably, the process of drying is as follows: Place the mixed powder in a glass beaker, put it into a vacuum drying oven, and dry it at 100 °C - 120 °C for 5 h - 10 h.

[0026] Preferably, a titanium alloy substrate thickness greater than 3 cm can prevent the deformation of the substrate caused by thermal stress.

[0027] Preferably, the laser scanning strategy for additive manufacturing is as follows: serpentine reciprocating scanning within a layer, rotating 90° between layers, laser power: 500 W - 900 W, scanning speed: 500 mm / min - 800 mm / min, powder feeding rate: 3% - 5%, and the cabin will be purged to reduce the oxygen content before printing, and the oxygen content is lower than 200 ppm.

[0028] Preferably, the matrix powder is a titanium alloy powder, and the titanium alloy powder is an α-titanium alloy, a β-titanium alloy or an (α + β) dual-phase titanium alloy.

[0029] Preferably, the sizes of the original additives include nanoscale and micron-scale, the morphologies of the reinforcing phase raw materials include irregular granular, spherical granular, flaky, and the forms of the reinforcing phase include compounds and elements.

[0030] Preferably, the morphology of the reinforcing phase includes granular, whisker-like, needle-like or plate-like shapes.

[0031] The present invention also provides a titanium matrix composite with adjustable and controllable reinforcing phase structure, which is prepared by the preparation method of the titanium matrix composite with adjustable and controllable reinforcing phase structure.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows: By controlling the particle size of the reinforcing phase raw material to the nanometer level, the in-situ reaction of the reinforcing phase is more sufficient and uniform, playing a better role in refining the matrix phase. Then, by regulating the mass percentage of the reinforcing phase raw material in the mixed powder, the present invention can obtain reinforcing phases with different micro-morphologies and spatial distributions, so as to realize the selectable and controllable high strength and plasticity of the titanium matrix composite.

[0033] At the same time, during the laser melting deposition process, the in-situ generated ceramic reinforcing phase plays a role in refining the initial β-Ti. As the molten pool temperature decreases, the reinforcing phase enriched at the grain boundaries of the initial β-Ti restricts the solidification of the matrix within the network, and the α lamellae within the network are mainly short rod-shaped; the reinforcing phase promotes the nucleation of α at the edge of the network structure and hinders its growth, and the formed fine and equiaxed α grains attach to the edge of the network structure to construct a network distribution structure of the matrix α phase. Therefore, compared with the titanium matrix composite prepared by the existing powder metallurgy method, the high strength and plasticity of the titanium matrix composite provided by the present invention are improved. Description of the Drawings

[0034] Figure 1 It is the SEM image of the network structure of the titanium matrix composite prepared in Example 1, and the white network is formed by the reinforcing phase.

[0035] Figure 2 It is the SEM image of the network structure of the titanium matrix composite prepared in Example 2, and the white network is formed by the reinforcing phase.

[0036] Figure 3 It is the SEM image of the network structure of the titanium matrix composite prepared in Example 3, and the white network is formed by the reinforcing phase.

[0037] Figure 4 It is the SEM image of the network structure of the titanium matrix composite prepared in Example 4, and the white network is formed by the reinforcing phase.

[0038] Figure 5 It is the SEM image of the network structure of the titanium matrix composite prepared in Example 5, and the white network is formed by the reinforcing phase.

[0039] Figure 6 It is the SEM image of the network structure of the titanium matrix composite prepared in Example 6, and the white network and the dispersed white granular are the reinforcing phase.

[0040] Figure 7 It is the SEM image of the reticular structure of the titanium matrix composite prepared in Example 7. The white granular particles are the reinforcement phase (indicated by the arrow).

[0041] Figure 8 It is the SEM image of the reticular structure of the titanium matrix composite prepared in Example 8. The white network is composed of the reinforcement phase.

[0042] Figure 9 It is the SEM image of the reticular structure of the titanium matrix composite prepared in Example 9. The white granular, needle-shaped, and segment rod-shaped particles are the reinforcement phase.

[0043] Figure 10 It is the SEM image of the reticular structure of the titanium matrix composite prepared in Comparative Example 1. The white granular particles are the reinforcement phase (indicated by the arrow).

[0044] Figure 11 It is the SEM image of the reticular structure of the titanium matrix composite prepared in Example 10. The white network is formed by the reinforcement phase. Detailed implementation manners

[0045] The following specific examples are given to describe the present invention in further detail.

[0046] Example 1: Using TC4 (Ti6Al4V) titanium alloy powder as the matrix powder, with a particle size of 50 μm - 150 μm, and using B4C powder as the original additive of the reinforcement phase for in-situ reaction, with a particle size of 2 μm - 4 μm, and the addition amount of B4C being 0.27 wt.%. The rotational speed of the mixed powder ball milling parameters is 200 r / min, the time is 5 h, the rotation direction of the ball mill is changed every 30 min, and it is paused for 5 min, and the ball-to-powder ratio is 3:1.

[0047] Additive manufacturing forming: The mixed powder is sent to the surface of the substrate through a powder feeding air flow, and the laser melts it to form a molten pool. As the laser head moves unidirectionally, a single track is formed, and the single tracks overlap with each other to form a layer; after printing one layer, the laser head moves up 0.37 mm, and the process of molten pool → single track → layer deposition is repeated, and the number of printed layers > 100 layers. Finally, an ultra-high strength heat-resistant titanium matrix composite is obtained by the method of layer-by-layer deposition.

[0048] The laser power is 800 W, the powder feeding rate is 5%, the overlapping rate is 40%, and the scanning speed is 700 mm / min; as Figure 1 shown, the obtained reinforcement phase is TiB + TiC, the average size of the reticular structure is 16 μm, the tensile strength at room temperature is 1152 MPa, and the elongation at break is 8.4%.

[0049] Example 2: The difference between this example and Example 1 lies in that the addition amount of B4C is 0.55 wt.%. As Figure 2 shown, the average size of the network structure in this example is 10 μm, the maximum tensile strength at room temperature is 1310 MPa, and the elongation at break is 7.5%.

[0050] Example 3: The difference between this example and Example 1 lies in that the addition amount of B4C is 1.1 wt.%. As Figure 3 shown, the average size of the network structure in this example is 7 μm, the tensile strength at room temperature is 1283 MPa, and the elongation at break is 3.7%.

[0051] Example 4: Using TA15 (Ti6.5Al2Zr1Mo1V) titanium alloy powder as the matrix powder, and TiB2 and La2O3 powders as the original additives of the reinforcing phase for in-situ reaction. The particle size of TiB2 is 3 - 5 μm, the particle size of La2O3 is 1 - 3 μm, the addition amount of TiB2 powder is 0.7 wt.%, and the addition amount of La2O3 is 0.1 wt.%.

[0052] Additive manufacturing forming: The mixed powder is sent to the surface of the substrate through the powder feeding air flow, and the laser melts it to form a molten pool. As the laser head moves unidirectionally, a single track is formed, and the single tracks overlap with each other to form a layer; after printing one layer, the laser head moves up 0.4 mm, and the process of molten pool → single track → layer is repeated. The number of printed layers > 100, and finally an ultra-high strength heat-resistant titanium matrix composite material is obtained by layer-by-layer deposition.

[0053] The printing power is 900 W, the powder feeding rate is 5%, the overlapping rate is 40%, the scanning speed is 600 mm / min, the ball milling parameters are the same as those in Example 1, and the obtained reinforcing phase by reaction is TiB + Ti2O 3。 As Figure 4 shown, the distribution of the reinforcing phase in this example shows a network structure, with an average size of 10 μm, a tensile strength at room temperature of 1350 MPa, and an elongation at break of 6.5%.

[0054] Example 5: Using TA1 titanium alloy powder as the matrix powder, and LaB6 powder as the original additive of the reinforcing phase for in-situ reaction. Its particle size is 50 nm, the addition amount of LaB6 is 0.7 wt.%, the printing power is 800 W, the scanning speed is 700 mm / min, the ball milling parameters are the same as those in Example 1, and the obtained reinforcing phase by reaction is TiB + Ti2O 3。 As Figure 5 shown, the distribution of the reinforcing phase in this example shows a network structure, with an average size of 7 μm, a tensile strength at room temperature of 780 MPa, and an elongation at break of 19.5%.

[0055] Based on Examples 1 - 5, a reticular distribution of the reinforcing phase was achieved in different titanium alloy systems.

[0056] Example 6: The difference between this example and Example 1 is that the B4C particle size is 50 nm and the addition amount is 0.5 wt.%. As Figure 6 shown, in this example, the reinforcing phase exhibits a mixed mode of reticular structure and sporadic dispersion inside the reticular structure. The room-temperature tensile strength is 1245 MPa, and the elongation at break is 6%.

[0057] Based on Examples 1 - 6, when the reinforcing phase presents a reticular distribution, the matrix phase size presents a reticular distribution with the same distribution law, that is, the matrix phase size at the reticular edge of the reinforcing phase is smaller, and the matrix phase size inside the reticular is larger. It can be seen that by designing the parameters of the original additive of the reinforcing phase, a reticular distribution of the reinforcing phase and a reticular distribution of the matrix phase size are achieved.

[0058] Example 7: The difference between this example and Example 6 is that the addition amount of B4C particles is 0.1 wt.%. As Figure 7 shown, in this example, the reticular structure is not obvious. A small amount of the reinforcing phase is pinned at the grain boundaries and inside the grains, and the main body shows a dispersed distribution. The room-temperature tensile strength is 1168 MPa, and the elongation at break is 10.6%.

[0059] Example 8: The difference between this example and Example 7 is that the B4C particle size is 2 - 4 μm. As Figure 8 shown, in this example, the reticular structure is not obvious. The reinforcing phase is mainly pinned at the grain boundaries, and the main body shows a reticular distribution. The room-temperature tensile strength is 1106 MPa, and the elongation at break is 8%.

[0060] Based on Examples 7 and 8, at a trace addition amount, when the reinforcing phase raw material is at the nanometer level, a small amount of the reinforcing phase precipitates at the grain boundaries and inside the boundaries. The matrix phase size is smaller, the morphology is short-axisized and more uniform.

[0061] Based on Examples 6 and 7, the regulation of the reinforcing phase from dispersion to reticulation is achieved.

[0062] Example 9: The difference between this example and Example 1 is that the addition amount of B4C is 2.75 wt.%. As Figure 9 shown, in this example, the reticular structure is not obvious. The reinforcing phase shows a dispersed or locally aggregated distribution. The room-temperature tensile strength is 1235 MPa, and the elongation at break is 1.5%.

[0063] Compared with Examples 7 and 8, the microhardness of the material is higher at this addition amount, and it is more wear-resistant and heat-resistant. It can be seen that by regulating the volume fraction of the dispersed distribution of the reinforcing phase, performance regulation can be achieved.

[0064] Based on Examples 1-3 and Example 9, the enhanced phase is realized to be distributed from a network structure to a dispersed structure.

[0065] Based on Examples 1-9, one or more of granular, whisker-like, needle-like, and plate-like enhanced phase particles are realized in a titanium matrix composite.

[0066] Example 10: The difference between this example and Example 6 is that the addition amount of B4C particles is 1 wt.%. As Figure 11 shown, under this example, the enhanced phase is distributed in a network structure with relatively large size, the tensile strength at room temperature is 1256 MPa, and the fracture elongation is 5%.

[0067] Comparative Example 1: The difference between this example and Example 6 is that the addition amount of B4C particles is 0.01 wt.%. As Figure 10 shown, under this example, a very small amount of enhanced phase pins at grain boundaries and within grains, the matrix phase is not effectively refined and short-axisized, the tensile strength at room temperature is 1044 MPa, and the fracture elongation is 11%.

[0068] As described above, by adjusting the composition parameters and printing parameters, the adjustable and controllable enhanced phase structure in a variety of titanium alloy matrices is realized. The above-mentioned examples and comparative examples do not impose any formal limitations on the present invention. Any person skilled in the art, without departing from the scope of the technical solution of the present invention, according to the technical essence of the present invention, any simple modification, equivalent replacement, and improvement made to the above examples all fall within the protection scope of the technical solution of the present invention.

Claims

1. A method for preparing a titanium-based composite material with an adjustable and controllable reinforcement phase structure, characterized in that: include: The matrix powder and the reinforcement phase raw material are mixed, ball-milled, and dried to obtain a mixed powder; The titanium-based composite material is obtained by printing the mixed powder onto a titanium alloy substrate through additive manufacturing; Among them, when the particle size of the reinforcing phase raw material is nanometer level and the mass percentage of the reinforcing phase raw material in the mixed powder is 0.01% - 2%, as the mass percentage of the reinforcing phase raw material decreases, the structural transformation process of the reinforcing phase in the obtained titanium-based composite material is network → network and dispersed coexistence → dispersed.

2. The method for preparing a titanium-based composite material with an adjustable and controllable reinforcement phase structure according to claim 1, characterized in that: When the particle size of the reinforcement phase raw material is nanometer-level and the mass percentage of the reinforcement phase raw material is 1% - 2%, the structure of the reinforcement phase in the titanium-based composite material is a network structure; When the particle size of the reinforcement phase raw material is nanometer-level, and the mass percentage of the reinforcement phase raw material is 0.1% - 0.5%, excluding the end point of 0.1%, the structure of the reinforcement phase in the titanium-based composite material is a mixed structure of network and dispersion coexistence; When the particle size of the reinforcement phase raw material is at nanometer level, and the mass percentage of the reinforcement phase raw material is less than or equal to 0.1% and greater than 0.01%, the structure of the reinforcement phase in the titanium-based composite material is a dispersed structure.

3. The method for preparing a titanium-based composite material with an adjustable and controllable reinforcement phase structure according to claim 2, characterized in that: The reinforcing phase raw material is B4C, and the matrix powder is TC4.

4. The method for preparing a titanium-based composite material with an adjustable and controllable reinforcement phase structure according to claim 2, characterized in that: The particle size of the reinforcing phase raw material is 1 nm - 100 nm.

5. The method for preparing a titanium-based composite material with an adjustable and controllable reinforcement phase structure according to claim 1, characterized in that: When the particle size of the reinforcement phase raw material is at the micron level, and the mass percentage of the reinforcement phase raw material in the mixed powder is 0.1%-2.5%, the structure of the reinforcement phase in the titanium-based composite material is a network structure; When the particle size of the reinforcement phase raw material is at the micron level, and the mass percentage of the reinforcement phase raw material in the mixed powder is less than 0.1%, the structure of the reinforcement phase in the titanium-based composite material is dispersed distribution; When the particle size of the reinforcement phase raw material is at the micron level and the mass percentage of the reinforcement phase raw material in the mixed powder is greater than 2.5%, the structure of the reinforcement phase in the titanium-based composite material is a high-density dispersed distribution or a locally aggregated distribution.

6. The method for preparing a titanium-based composite material with an adjustable and controllable reinforcement phase structure according to claim 5, characterized in that: The particle size of the reinforcing phase raw material is 1 μm - 10 μm.

7. The method for preparing a titanium-based composite material with an adjustable and controllable reinforcement phase structure according to claim 5, characterized in that: The reinforcing phase raw material is B4C, the matrix powder is TC4, the mass percentage of the reinforcing phase raw material in the mixed powder is 0.1%-2.5%, and when the mass percentage of the reinforcing phase raw material in the mixed powder increases, the size of the network structure decreases.

8. The method for preparing a titanium-based composite material with an adjustable and controllable reinforcement phase structure according to claim 1 or 5, characterized in that: The reinforcing phase raw material is B4C, La2O3, TiB2 or LaB6, and the matrix powder is TC4, TA15, TA1 or TC18.

9. The method for preparing a titanium-based composite material with an adjustable and controllable reinforcement phase structure according to claim 1, characterized in that: The laser scanning strategy for additive manufacturing is: serpentine reciprocating scanning within the layer, and 90° rotation between layers; laser power is: 500 W - 1000 W, scanning speed is: 500 mm / min - 800 mm / min; powder feeding rate is: 3% - 5%; before printing, the cabin will be purged and oxygen content will be reduced, and the oxygen content will be less than 200 ppm.

10. A titanium-based composite material with adjustable and controllable reinforcement phase structure, characterized in that: It is prepared by the method for preparing a titanium-based composite material with an adjustable and controllable reinforcing phase structure as described in any one of claims 1 to 9.

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