Spherical titanium-based composite powder and preparation method thereof

Abstract

The invention relates to spherical titanium-based composite powder and a preparation method thereof, and belongs to the technical field of chemical materials. According to the spherical titanium-based composite powder, a base body is titanium or titanium alloy, a reinforcing phase is TiBw, and the titanium alloy is selected from IMI834 alloy or TC4 alloy; the sphericity degree of the spherical titanium-based composite powder is larger than or equal to 98%, the Hall flow velocity is 20-35 s / 50 g, the apparent density is 2.0-2.8 g / cm < 3 >, the oxygen content is 600-1100 ppm, the nanoindentation strength is 6-10 GPa, the grain size is 1-6 microns, and the TiBw diameter is 5-30 nm. According to the method, titanium alloy serves as a matrix, TiB2 serves as a reinforcing phase reactant, a radio frequency plasma spheroidizing technology and a hydrogenation crushing method are combined, the TiBw is refined to the nanoscale and evenly distributed by means of the rapid cooling characteristic of high-temperature plasma, and grain refinement and accurate regulation and control on morphology, granularity and components are achieved.

Description

Technical Field

[0001] This invention relates to the field of chemical materials technology, and in particular to a spherical titanium-based composite powder and its preparation method. Background Technology

[0002] As the requirements for material performance under extreme service environments become increasingly stringent for next-generation aero-engines, advanced gas turbines, and deep-sea operation equipment, titanium-based composite materials introduce TiB into the titanium alloy matrix. w Titanium-based composites, with reinforcing phases such as TiC, possess excellent specific strength, thermal stability, and corrosion resistance, and are expected to achieve stable service under extreme conditions such as high temperature, high corrosion, and high load. However, in practical applications such as additive manufacturing of complex components, titanium-based composites still face many key bottlenecks, including poor sphericity and purity of raw material powders and severe agglomeration of reinforcing phases. In particular, during the service life of components, the size, distribution, and interfacial bonding state of the reinforcing phase have a significant impact on the crack initiation and propagation path and mechanical properties.

[0003] TiB in additive manufacturing w The size, aspect ratio, and distribution of the reinforcing phase have a significant impact on the mechanical properties of titanium matrix composites. When TiB w When present in the matrix at the nanoscale, TiB can effectively hinder dislocation climb and slip, suppress grain growth, refine matrix grains, and significantly enhance dislocation strengthening and grain refinement effects. Furthermore, nanoscale TiB... w It has a good effect on coordinating deformation, reduces stress concentration during plastic deformation, and reduces the probability of crack initiation and propagation inside the reinforced body, thus better exerting the strengthening effect.

[0004] Currently, the raw materials used in additive manufacturing of titanium-based composite materials are generally obtained by mixing the matrix and the reinforcing phase. This process deteriorates the sphericity and flowability of the powder, and uneven mixing can easily lead to localized agglomeration of the reinforcing phase in the matrix, severely reducing material properties. Pre-alloyed powder, on the other hand, is prepared by turning the pre-composite material into a powder. It not only better inherits the distribution characteristics of the reinforcing phase in the composite material but also allows for the high-speed refining of the reinforcing phase using powder-making technologies such as gas atomization. Pre-alloyed composite powder can be used in additive manufacturing processes to create unique nanoscale network structures, further improving the material's mechanical properties. Current methods for preparing pre-alloyed composite powder include the plasma rotating electrode method and the induction melting gas atomization method.

[0005] The electro-induction melting gas atomization (EIGA) powder production process is as follows: First, the matrix powder is mixed with the reinforcing phase, and then a composite material is obtained through methods such as vacuum consumable electrode melting. The composite material is mechanically shaped and used as the anode material in an induction furnace. It is slowly rotated and heated in a high-frequency inductor under an inert gas environment until it melts into a liquid state, thus falling to form a stable liquid flow. During the free fall, the molten metal flow is impacted by the high-speed inert gas and gradually forms a metal strip. The gas flow continues to impact the metal strip, causing it to break into small metal droplets. Subsequently, under the action of surface tension, these metal droplets gradually tend to become spherical and solidify during rapid cooling, finally obtaining pre-alloyed powder particles.

[0006] The PREP (Preparative Plasma Electrode Atomization) method uses a rod as the raw material, which serves as one end of the electrode. A plasma gun at the other end generates a plasma current. A motor drives the rod to rotate at high speed, generating centrifugal force that breaks up the molten metal solution, which then forms spherical powder under surface tension. The team led by Lü Weijie at Shanghai Jiao Tong University has used the PREP method to prepare titanium composite powder, specifically nano-TiB. w Nano-sized La2O3 particles are distributed along the primary β grain boundaries, forming a fine network structure of 2–10 μm in situ. TEM bright-field imaging reveals interlaced acicular martensite within the powder, with a width less than 100 nm, a typical rapidly solidified structure. Selected area electron diffraction confirmed its structure as orthorhombic martensite α''. This formation is attributed to the rapid cooling rate of PREP, the high concentration of β-stabilizing elements in the alloy, and the high resistance to lattice transformation, preventing a hexagonal lattice transformation and instead causing the β phase to transform into an orthorhombic lattice.

[0007] However, the EIGA process for preparing titanium-based composite powders is complex, resulting in powders with a wide particle size distribution, high oxygen content, and some hollow particles, requiring improvement in sphericity. The PREP process produces powders with uniform composition and high purity, but suffers from low efficiency, coarse metal powder particle size that fails to meet the requirements of powder bed laser melting, and incomplete utilization of the rod stock. Furthermore, both methods struggle to control the TiB content when preparing pre-alloyed titanium-based composite powders. w Size and distribution. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of the prior art and provide a spherical titanium-based composite powder and its preparation method.

[0009] To achieve the above objectives, the technical solution adopted by the present invention is as follows: In a first aspect, the present invention provides that the matrix of the spherical titanium-based composite powder is titanium or a titanium alloy, and the reinforcing phase is TiB. wThe titanium alloy is selected from IMI834 alloy or TC4 alloy; the sphericity of the spherical titanium-based composite powder is ≥98%, the Hall flow rate is 20~35 s / 50 g, and the loose packing density is 2.0~2.8 g / cm³. 3 Oxygen content is 600~1100 ppm, nanoindentation strength is 6~10 GPa, grain size is 1~6 μm, TiB w The diameter is 5~30 nm.

[0010] This invention uses titanium alloy as the matrix and TiB2 as the reinforcing phase. By combining the melting and casting hydrogenation crushing method with radio frequency plasma spheroidization, the spherical titanium-based composite powder prepared has high sphericity, low oxygen content, smooth powder surface, and significantly reduced nanosatellite powder. During the spheroidization process, the reinforcing phase is refined from needle-like to short rod-like and maintains good interfacial bonding with the matrix.

[0011] As a preferred embodiment of the spherical titanium-based composite powder of the present invention, the particle size of the spherical titanium-based composite powder is 10~150 μm.

[0012] In a preferred embodiment of the spherical titanium-based composite powder of the present invention, the mass of B in the spherical titanium-based composite powder is 0.3~1.2 wt.%.

[0013] Secondly, the present invention provides a method for preparing the spherical titanium-based composite powder, comprising the following steps: S1: Mix titanium or titanium alloy with TiB2 powder to obtain a mixed raw material, evacuate and fill with inert gas, and repeatedly melt at 1500~1600℃ to obtain an ingot; S2: The ingot from step S1 is subjected to hydrogenation, crushing and dehydrogenation treatment to obtain hydrogenation-dehydrogenation composite powder; S3: The hydrogenated and dehydrogenated composite powder from step S2 is subjected to radio frequency plasma spheroidization treatment to obtain the spherical titanium-based composite powder.

[0014] Radiofrequency plasma spheroidization features high energy, high enthalpy, and high cooling rate, enabling the spheroidization of TiB in titanium-based composite powders. w The refinement from micrometer to nanometer scale forms a network structure, allowing for the modulation of TiB by different cooling rates. w And nanoscale parameters of precipitated phases. Utilizing the strong reducing properties of hydrogen plasma, the content of impurities such as oxygen and nitrogen in the powder is purified, achieving controllable preparation of low-oxygen titanium-based composite powders with target particle size.

[0015] In a preferred embodiment of the preparation method described in this invention, in step S1, the mass of B in the mixed raw materials is 0.3~1.2 wt.%.

[0016] In a more preferred embodiment of the preparation method of the present invention, in step S1, the mass of B is 0.5~0.8 wt.%.

[0017] In the most preferred embodiment of the preparation method described in this invention, in step S1, the mass of B is 0.5 wt.%.

[0018] As a more preferred embodiment of the preparation method described in this invention, in step S1, the material is repeatedly melted at 1550°C.

[0019] In a preferred embodiment of the preparation method described in this invention, the number of repeated melting cycles in step S1 is 3 to 6.

[0020] In a more preferred embodiment of the preparation method described in this invention, the melting process is repeated 5 times in step S1.

[0021] In a preferred embodiment of the preparation method described in this invention, in step S1, the vacuum is evacuated to 3×10⁻⁶. 3 ~5×10 3 Pa.

[0022] As a more preferred embodiment of the preparation method described in this invention, in step S1, the vacuum is evacuated to 3×10⁻⁶. -3 Pa.

[0023] In a preferred embodiment of the preparation method of the present invention, in step S1, the inert gas includes at least one of nitrogen, argon and helium.

[0024] In a preferred embodiment of the preparation method described in this invention, in step S2, the particle size of the hydrogenation-dehydrogenation composite powder is 10~150 μm.

[0025] As a more preferred embodiment of the preparation method of the present invention, in step S2, the particle size of the hydrogenation-dehydrogenation composite powder is 53~106 μm.

[0026] As a more preferred embodiment of the preparation method of the present invention, in step S2, hydrogen gas at 0.5~1.5 MPa is first introduced into the hydrogenation furnace and kept at 750~1000℃ for 1~5 h, then the hydrogen pressure is reduced to 0.2~0.8 MPa and kept at 700~900℃ for 0.2~5 h, and after cooling, hydrogenated ingot is obtained. The hydrogenated ingot is crushed once to obtain hydrogenated powder, which is then sieved through a 100-mesh standard sieve to obtain hydrogenated powder that can pass through the 100-mesh standard sieve. Hydrogenated powder that does not pass through a 100-mesh standard sieve is placed in a hydrogenation furnace, and hydrogen gas at 0.2~2 MPa is introduced into the hydrogenation furnace. The furnace is kept at 700~1000℃ for 2~5 h, and then cooled to obtain a secondary hydrogenated ingot. The secondary hydrogenated ingot is crushed a second time to obtain secondary hydrogenated powder, which is then sieved through a 100-mesh standard sieve to obtain hydrogenated powder that can pass through the 100-mesh standard sieve. Hydrogenated powders that can pass through a 100-mesh standard sieve are mixed to obtain hydrogenated dehydrogenated composite powders.

[0027] In the most preferred embodiment of the preparation method described in this invention, in step S2, hydrogen gas at 0.5 MPa is first introduced into the hydrogenation furnace and kept at 900°C for 1.5 h. Then, the hydrogen gas pressure is reduced to 0.25 MPa and kept at 900°C for 0.5 h. After cooling, hydrogenated ingots are obtained. The hydrogenated ingot is crushed once to obtain hydrogenated powder, which is then sieved through a 100-mesh standard sieve to obtain hydrogenated powder that can pass through the 100-mesh standard sieve. Hydrogenated powder that does not pass through a 100-mesh standard sieve is placed in a hydrogenation furnace, hydrogen gas at 0.25 MPa is introduced into the hydrogenation furnace, and the furnace is kept at 900℃ for 2.5 h. After cooling, a secondary hydrogenated ingot is obtained. The secondary hydrogenated ingot is crushed to obtain secondary hydrogenated powder, which is then sieved through a 100-mesh standard sieve to obtain hydrogenated powder that can pass through the 100-mesh standard sieve. Hydrogenated powders that can pass through a 100-mesh standard sieve are mixed to obtain hydrogenated dehydrogenated composite powders.

[0028] In a preferred embodiment of the preparation method described in this invention, the parameters for the radio frequency plasma spheroidization treatment in step S3 are as follows: the turntable speed is 1~10 rpm, the carrier gas flow rate is 1~8 L / min, the dispersion gas flow rate is 0~2 L / min, the center gas flow rate is 15~25 L / min, the first sheath gas flow rate is 40~60 L / min, the second sheath gas flow rate is 3~12 L / min, the plasma power is 20~40 kW, and the powder feeding rate is 5~60 g / min.

[0029] As a more preferred embodiment of the preparation method described in this invention, in step S3, the parameters of the spheroidization treatment by radio frequency plasma are as follows: the turntable speed is 4 rpm, the carrier gas flow rate is 4 L / min, the dispersion gas flow rate is 1.5 L / min, the center gas flow rate is 22 L / min, the first sheath gas flow rate is 55 L / min, the second sheath gas flow rate is 8 L / min, the plasma power is 35 kW, and the powder feeding rate is 30 g / min.

[0030] In a more preferred embodiment of the preparation method described in this invention, in step S3, the first sheath gas includes argon gas.

[0031] As a more preferred embodiment of the preparation method of the present invention, in step S3, the second sheath gas includes hydrogen and / or argon.

[0032] As a more preferred embodiment of the preparation method of the present invention, in step S3, the hydrogenated dehydrogenated composite powder of step S2 is subjected to radio frequency plasma spheroidization treatment to obtain spheroidized powder, and then subjected to wet fluidized bed micro-nano classification treatment to obtain the spherical titanium-based composite powder.

[0033] As a more preferred embodiment of the preparation method described in this invention, in step S3, the ultrasonic frequency of the wet fluidized bed micro-nano classification process is 20~100 kHz, and the flow rate is 0.5~5 L / min.

[0034] In the most preferred embodiment of the preparation method described in this invention, in step S3, the ultrasonic frequency of the wet fluidized bed micro-nano classification process is 20 kHz and the flow rate is 2 L / min.

[0035] Compared with the prior art, the beneficial effects of the present invention are as follows: TiB for conventional additive manufacturing w Titanium-based composite powders prepared by ball milling and mixing suffer from impaired powder sphericity and severe agglomeration of the reinforcing phase, leading to stress cracking in the formed parts and a severe strength-ductility inversion in mechanical properties. This invention uses a titanium alloy as the matrix and TiB2 as the reinforcing phase reactant. The mixture is smelted in a high-vacuum levitation melting furnace, and then radio frequency plasma spheroidization technology is combined with hydrogenation crushing. Utilizing the rapid cooling characteristics of high-temperature plasma, micron-sized TiB2 generated in situ within the ingot is removed. w Refining to the nanoscale enables the refinement of composite powder grains, improves the distribution of precipitated phases, and achieves precise synergistic control over morphology, particle size, and composition. Attached Figure Description

[0036] Figure 1 Spherical IMI834-TiB prepared in Example 1 w Particle size distribution of composite powder before and after spheroidization. Where a represents before spheroidization; b represents after spheroidization.

[0037] Figure 2 Spherical IMI834-TiB prepared in Example 1 w Morphology of the composite powder before and after spheroidization. Where a represents before spheroidization; b represents after spheroidization.

[0038] Figure 3 The XRD patterns of titanium-based composite powder materials at different preparation stages are shown in the following order from top to bottom: step (1) casting, step (2) hydrogenation-dehydrogenation crushing process, step (3) plasma spheroidization, and step (4) wet fluidized bed micro-nano classification.

[0039] Figure 4The figures show cross-sectional views of the titanium-based composite powder before and after plasma spheroidization; where a is the phase diagram of the hydrogenated and dehydrogenated composite powder before spheroidization; b is the phase diagram of the titanium-based composite powder after spheroidization; c is the IPF diagram of the hydrogenated and dehydrogenated composite powder before spheroidization; and d is the IPF diagram of the titanium-based composite powder after spheroidization.

[0040] Figure 5 TiB titanium-based composite powder before and after spheroidization w Morphology diagram. Where a represents TiB before spheroidization. w Morphology; b represents TiB after spheroidization. w Appearance.

[0041] Figure 6 The spherical IMI834-TiB obtained in Example 1 w The silicides in the composite powder precipitate with TiBw as the heterogeneous nucleation site.

[0042] Figure 7 The titanium alloy powder prepared for Comparative Example 1 is shown. In the figure, a is the phase diagram of the titanium alloy powder; b is the IPF diagram of the titanium alloy powder.

[0043] Figure 8 Spherical IMI834-TiB prepared under different radio frequency plasma spheroidizing atmospheres w Composite powder. Where a represents spherical IMI834-TiB prepared in Comparative Example 2 under a pure argon atmosphere. w Cross-sectional morphology of the composite powder; b is the spherical IMI834-TiB prepared in Example 1 under hydrogen atmosphere. w Cross-sectional morphology of composite powder. Detailed Implementation

[0044] To better illustrate the purpose, technical solution, and advantages of this invention, the invention will be further described below with reference to specific embodiments. Unless otherwise specified, other materials and reagents used in the embodiments are commercially available.

[0045] The typical composition (mass percentage) of IMI834 alloy is Al 5.6%~5.9%, Sn 3.5%~3.8%, Zr 0.6%~0.8%, Mo 0.8%~1.2%, Si 0.2%~0.4%, C≤0.03%, with the balance being Ti.

[0046] TiB2 ceramic powder, preferably with a particle size ≤20 μm.

[0047] The preferred B equivalent is 0.5 wt.%. Within the range of B equivalent adjustment, the reinforcing phase precursor can react in situ to generate TiB whiskers; when the content is below 0.3 wt.%, the reinforcement is insufficient, and when it is above 0.7 wt.%, it is prone to agglomeration and brittle phase.

[0048] Example 1 IMI834 alloy melt particles were used as the matrix alloy, and TiB2 ceramic powder was used as the reinforcing phase precursor. The melting was carried out in a YC-20160024 high-vacuum suspension melting furnace.

[0049] The preparation method is as follows: (1) IMI834 alloy element melt particles (mass percentage of each element is: Al 5.9%, Sn 3.8%, Zr 0.7%, Mo 0.8%, Si 0.3%, C 0.03% and Ti 88.47%) and TiB2 ceramic powder are mixed to obtain a mixed raw material, so that the mass percentage of B in the mixed raw material is 0.5%, and it is placed in a water-cooled copper crucible and vacuumed to 3×10 -3 Pa, high-purity argon gas is introduced as a protective atmosphere, and suspension melting is carried out at 1550℃. The process is repeated 5 times to ensure uniform alloy composition, resulting in an ingot.

[0050] (2) The ingot obtained in step (1) is subjected to hydrogenation-dehydrogenation crushing process to obtain irregular composite powder with a particle size of 53~106 μm.

[0051] The ingot is placed in a hydrogenation furnace. First, hydrogen gas at 0.5 MPa is introduced into the hydrogenation furnace and held at 900℃ for 1.5 h. Then, the hydrogen gas pressure is reduced to 0.25 MPa and held at 900℃ for 0.5 h. After cooling, the hydrogenated ingot is obtained. Primary crushing: The hydrogenated ingot is crushed to obtain hydrogenated powder; it is then sieved through a 100-mesh standard sieve to obtain hydrogenated powder that can pass through the 100-mesh standard sieve. Secondary hydrogenation: The hydrogenated powder that fails to pass through the 100-mesh standard sieve is placed in a hydrogenation furnace, hydrogen gas at 0.25 MPa is introduced into the hydrogenation furnace, and the furnace is kept at 900℃ for 2.5 h. After cooling, a secondary hydrogenated ingot is obtained. Secondary crushing: The secondary hydrogenated ingot is crushed and sieved through a 100-mesh standard sieve to obtain hydrogenated powder that can pass through a 100-mesh standard sieve. The hydrogenated powder obtained by mixing can pass through a 100-mesh standard sieve to obtain a hydrogenated dehydrogenated composite powder.

[0052] (3) The hydrogenated dehydrogenated composite powder from step (2) was spheroidized using a Tekna 40 kW radio frequency plasma spheroidizing device to obtain spheroidized powder. The parameters were: turntable speed 4 rpm, carrier gas flow rate 4 L / min, dispersion gas flow rate 1.5 L / min, center gas flow rate 22 L / min, first sheath gas (Ar) 55 L / min, second sheath gas (H2) 8 L / min, plasma power 35 kW, and powder feeding rate 30 g / min.

[0053] (4) The spheroidized powder was subjected to wet fluidized bed micro-nano classification with an ultrasonic frequency of 20 kHz and a flow rate of 2 L / min to remove the surface-adhered nanosatellite powder and obtain spherical IMI834-TiB. w Composite powder.

[0054] Example 2 The spherical IMI834-TiB prepared in Example 1 w The composite powder was tested, and the results showed that IMI834-TiB w The composite powder has a sphericity ≥98%, a Hall flow rate of 21.8 s / 50 g, and a bulk density of 2.7 g / cm³. 3 The oxygen content is 880 ppm, the nanoindentation hardness is 9 GPa, and the average particle size is 45.98 μm. (TiB) w Diameter 10 nm, grain size 4 μm ( Figure 1 a). Compared to the hydrogenated dehydrogenated composite powder obtained in Example 1 (oxygen content approximately 1200 ppm, sphericity 0, no flowability, nanoindentation hardness 2.5 GPa, average particle size 67.29 μm), Figure 1 b) All indicators have improved significantly.

[0055] like Figure 2 a and Figure 2 As shown in b, SEM (scanning electron microscopy) observation revealed spherical IMI834-TiB w The composite powder has a smooth surface and a significant reduction in nanosatellite powder; the results further reveal the spherical IMI834-TiB w TiB in composite powder w The reinforcing phase refines from rod-shaped to needle-shaped during the spheroidization process.

[0056] XRD (X-ray diffraction) analysis results indicate that the spherical IMI834-TiB w The main phases of the composite powder are α'-Ti matrix phase and TiB. w ( Figure 3 ).

[0057] As shown in Table 1, the spherical IMI834-TiB prepared in Example 1 w Compared to the hydrogenated dehydrogenated composite powder obtained in Example 1, the hardness and elastic modulus of the composite powder are effectively improved.

[0058] Table 1 Depend on Figure 4 a and Figure 4 b, Figure 4 c and Figure 4 As can be seen from the comparison, the TiB composite powder after spheroidization...w The grain size was significantly refined.

[0059] Depend on Figure 5 a and Figure 5 As can be seen from the comparison, after spheroidization, the TiB composite powder... w Refining from the micrometer scale to the nanometer scale.

[0060] like Figure 6 As shown, the spherical IMI834-TiB obtained in Example 1 w The silicides in the composite powder precipitate with TiBw as the heterogeneous nucleation site.

[0061] Example 3 The IMI834 alloy melt particles in Example 1 were replaced with TC4 alloy melt particles (mass percentage of each element: Al 6%, V 4%, Ti 90%), and the other preparation methods were the same to obtain spherical TC4-TiB. w Composite powder.

[0062] Tests showed that spherical TC4-TiB w The composite powder has a flowability of 24 s / 50g and a bulk density of 2.36 g / cm³. 3 Nanoindentation hardness 6.5 GPa, oxygen content 900 ppm, TiB w Diameter 12 nm, grain size 5 μm.

[0063] Comparative Example 1 The difference from Example 1 is that TiB2 is not added, but everything else is the same.

[0064] like Figure 7 a and Figure 7 As shown in b, the sphericity of the obtained powder is ≥95%, the Hall flow rate is 26.8 s / 50 g, and the bulk density reaches 2.6 g / cm³. 3 The oxygen content is 1000 ppm, the nanoindentation hardness is 6.5 GPa, the average particle size is 36.24 μm, the grain size is 15 μm, and the composite powder was prepared without the addition of TiB2 during the melting process. The grain size is large, and the powder is mainly β-Ti.

[0065] Comparative Example 2 The difference from Example 1 is that the atmosphere is pure argon, and no hydrogen is added.

[0066] like Figure 8 a and Figure 8 As shown in b, the sphericity of the obtained powder is ≥95%, the Hall flow rate is 27.6 s / 50 g, and the bulk density reaches 2.5 g / cm³. 3The oxygen content was 1300 ppm, the nanoindentation hardness was 5.2 GPa, the average particle size was 34.24 μm, and the grain size was 3 μm. This indicates that the grain refinement effect of the composite powder was worse without the addition of hydrogen.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A spherical titanium-based composite powder, characterized in that, The matrix of the spherical titanium-based composite powder is titanium or a titanium alloy, and the reinforcing phase is TiB. w The titanium alloy is selected from IMI834 alloy or TC4 alloy; the sphericity of the spherical titanium-based composite powder is ≥98%, the Hall flow rate is 20~35 s / 50 g, and the loose packing density is 2.0~2.8 g / cm³. 3 Oxygen content is 600~1100 ppm, nanoindentation strength is 6~10 GPa, grain size is 1~6 μm, TiB w The diameter is 5~30 nm.

2. The spherical titanium-based composite powder as described in claim 1, characterized in that, The spherical titanium-based composite powder has a particle size of 10~100 μm.

3. The spherical titanium-based composite powder as described in claim 1, characterized in that, The mass of B in the spherical titanium-based composite powder is 0.3~1.2 wt.%.

4. The method for preparing the spherical titanium-based composite powder according to any one of claims 1 to 3, characterized in that, Includes the following steps: S1: Mix titanium or titanium alloy with TiB2 powder to obtain a mixed raw material, evacuate and fill with inert gas, and repeatedly melt at 1500~1600℃ to obtain an ingot; S2: The ingot from step S1 is subjected to hydrogenation, crushing and dehydrogenation treatment to obtain hydrogenation-dehydrogenation composite powder; S3: The hydrogenated and dehydrogenated composite powder from step S2 is subjected to radio frequency plasma spheroidization treatment to obtain the spherical titanium-based composite powder.

5. The preparation method according to claim 4, characterized in that, In step S1, the mass of B in the mixed raw materials is 0.3~1.2 wt.%.

6. The preparation method according to claim 4, characterized in that, In step S1, the melting process is repeated 3 to 6 times.

7. The preparation method according to claim 4, characterized in that, In step S2, the particle size of the hydrogenation-dehydrogenation composite powder is 10~100 μm.

8. The preparation method according to claim 4, characterized in that, In step S3, the parameters for RF plasma spheroidization treatment are as follows: turntable speed is 1~10 rpm, carrier gas flow rate is 1~8 L / min, dispersion gas flow rate is 0~2 L / min, center gas flow rate is 15~25 L / min, first sheath gas flow rate is 40~60 L / min, second sheath gas flow rate is 3~12 L / min, plasma power is 20~40 kW, and powder feeding rate is 5~60 g / min.

9. The preparation method according to claim 8, characterized in that, The first sheath gas is selected from argon and / or helium; the second sheath gas is selected from at least one of argon, helium and hydrogen.

10. The preparation method according to claim 4, characterized in that, In step S3, the hydrogenated dehydrogenated composite powder from step S2 is subjected to radio frequency plasma spheroidization treatment to obtain spheroidized powder, which is then subjected to wet fluidized bed micro-nano classification treatment to obtain the spherical titanium-based composite powder.

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