A method of making high performance injection molded titanium alloy articles with an oxygen getter

Abstract

The application discloses a method for preparing a high-performance injection-molded titanium alloy product by adding an oxygen absorbent, and comprises the following steps: (1) ball milling titanium alloy spherical powder and YB6 powder to obtain mixed powder; (2) mixing the mixed powder with a binder and performing compounding and granulation to obtain granular injection-molded titanium alloy product feed; (3) injecting the feed into a mold to obtain an injection-molded titanium alloy product green body; (4) catalytically debinding the green body to obtain a debound body; and (5) performing thermal debinding and sintering on the debound body to obtain the injection-molded titanium alloy product. The YB6 is used as the oxygen absorbent in the application, the oxygen content in the injection-molded titanium alloy product matrix is reduced, TiB and Y2O3 reinforcing phases are generated in situ, the synchronous improvement of the strength and plasticity is effectively realized, the high-performance injection-molded titanium alloy product is obtained, the injection-molded titanium alloy product obtained has low oxygen content, high density and excellent mechanical properties, and the development of the titanium and titanium alloy injection molding industry is promoted.

Description

Technical Field

[0001] This invention belongs to the field of powder metallurgy titanium technology, specifically relating to a method for preparing high-performance injection-molded titanium alloy products by adding an oxygen absorber. Background Technology

[0002] Titanium and titanium alloys possess a range of advantages, including low density, high specific strength, strong corrosion resistance, good biocompatibility, non-magnetic properties, and excellent heat resistance and low-temperature toughness. They play a vital role in various fields such as aerospace, shipbuilding, chemical engineering, medical applications, and automotive manufacturing, and are hailed as the "metal of the future." However, the poor machinability of titanium alloys poses significant challenges to the production of complex titanium alloy components.

[0003] Metal powder injection molding, as a near-net-shape forming technology, eliminates processing steps and offers advantages such as process flexibility, high material utilization, uniform microstructure, and fine grain size, making it highly suitable for the mass production of complex small (micro) titanium alloy parts. However, the titanium alloy powder used in injection molding has a small particle size (typically less than 25 μm), a large specific surface area, and titanium has a strong oxygen affinity, which easily leads to an increase in the oxygen content of the powder. The lower the oxygen content of the titanium alloy powder, the more expensive it is. Generally, the oxygen content in titanium alloys is required to be below 0.2 wt.%, as excessively high oxygen content severely deteriorates the plasticity of the titanium alloy. Therefore, controlling the oxygen content in titanium alloys is crucial for preparing high-performance injection-molded titanium alloy products. Summary of the Invention

[0004] The technical problem to be solved by this invention is to address the shortcomings of the prior art by providing a method for preparing high-performance injection-molded titanium alloy products by adding an oxygen absorber. This method involves thoroughly mixing YB6 powder with titanium alloy spherical powder, followed by intensive mixing and granulation, injection molding, debinding, and sintering. YB6 is used as an oxygen absorber to react with the oxygen in the titanium alloy spherical powder, reducing the oxygen content in the matrix of the injection-molded titanium alloy product. Simultaneously, TiB and Y2O3 reinforcing phases are generated in situ, effectively achieving a simultaneous improvement in strength and plasticity, resulting in high-performance injection-molded titanium alloy products.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a method for preparing high-performance injection-molded titanium alloy products by adding an oxygen absorber, characterized in that the method includes the following steps:

[0006] Step 1, Powder Mixing: Add titanium alloy spherical powder and YB6 powder to a ball mill jar, and fill with argon gas for protection. Then, use a ball mill to mix them evenly to obtain a mixed powder. The ball mill speed is 150 rpm to 300 rpm, the ball-to-material ratio is 4 to 7:1, and the ball milling time is 2 to 4 hours.

[0007] Step 2, Intensive Mixing and Granulation: The mixed powder obtained in Step 1 is mixed with the binder, and then subjected to intensive mixing under argon protection to obtain a mixture. The mixture is then granulated to obtain granular feedstock for injection molding titanium alloy products. The intensive mixing process is carried out at a temperature of 170℃~190℃, a rotation speed of 30rpm~40rpm, and a time of 1h~3h.

[0008] Step 3, Injection Molding: The granular injection-molded titanium alloy product obtained in Step 2 is fed into the hopper of the injection molding machine, then injected into the mold, and then cooled to obtain the injection-molded titanium alloy product blank; the injection pressure is 100MPa~200MPa, the injection temperature is 170℃~190℃, the injection speed is 140mm / s~180mm / s, and the cooling time is 5s~10s;

[0009] Step 4, Catalytic Degreasing: The injection-molded titanium alloy blank obtained in Step 3 is placed in an oxalic acid degreasing furnace for catalytic degreasing to obtain a degreased blank; the temperature of the catalytic degreasing is 110℃~130℃, and the time is 8h~12h.

[0010] Step 5, hot degreasing and sintering: The degreased blank obtained in step 4 is placed in a vacuum sintering furnace with a molybdenum heating element and heated to 500℃~600℃ at a heating rate of 1℃ / min~3℃ / min, and held for 3h~6h for hot degreasing. Then, the temperature is increased to 1200℃~1300℃ at a heating rate of 5℃ / min~7℃ / min and held for 2h~4h for sintering to obtain injection-molded titanium alloy products.

[0011] This invention achieves thorough and uniform mixing of spherical titanium alloy powder and oxygen absorber YB6 powder through ball milling and parameter control. Then, through intensive mixing and granulation with controlled parameters, the mixed powder and binder are fully integrated to obtain a uniformly dispersed granular feedstock for injection molding of titanium alloy products. Injection molding with controlled parameters transforms this granular feedstock into injection molded titanium alloy green blanks, ensuring good flowability for complete filling and preventing excessive flowability that could cause flash or burrs. Catalytic degreasing with controlled parameters removes the binder, and thermal degreasing with controlled parameters further removes residual binder. Finally, by controlling sintering parameters, densification and sintering of the injection-molded parts are achieved.

[0012] The above-described method for preparing high-performance injection-molded titanium alloy products by adding an oxygen absorber is characterized in that the titanium alloy spherical powder in step one is made of TA1, TC18, or TC4, the particle size of the titanium or titanium alloy spherical powder satisfies D90≤30μm, and the particle size of the YB6 powder is not greater than 20μm. This invention is applicable to the preparation of high-performance injection-molded titanium alloy products from titanium alloy spherical powders of various compositions. By controlling the particle size of the titanium or titanium alloy spherical powder, good feed flowability, sintering density, and surface quality are ensured. By controlling the particle size of the YB6 powder to be no greater than 20μm, the YB6 powder and the titanium alloy spherical powder can fully react with oxygen during sintering, ensuring the oxygen absorption effect.

[0013] The above-mentioned method for preparing high-performance injection-molded titanium alloy products by adding an oxygen absorber is characterized in that the mass ratio of titanium alloy spherical powder to YB6 powder in the mixed powder in step one is 99.4-99.8:0.2-0.6. This invention, by controlling the mass ratio of titanium alloy spherical powder to YB6 powder, ensures that the oxygen absorber can fully react with the oxygen element in the titanium alloy spherical powder while preventing the formation of excessive brittle phases that reduce plasticity.

[0014] The above-mentioned method for preparing high-performance injection-molded titanium alloy products by adding an oxygen absorber is characterized in that the binder in step two is a polyoxymethylene-based system, composed of the following components by mass fraction: 80%–85% polyoxymethylene, 5%–8% high-density polyethylene, 5%–8% ethylene-vinyl acetate copolymer, 1%–5% stearic acid, and 1%–3% hyperbranched polyamide resin. This invention, by controlling the composition of the binder, ensures that the feedstock has sufficient strength and flowability, while also achieving complete removal of the binder during degreasing.

[0015] The above-mentioned method for preparing high-performance injection-molded titanium alloy products by adding an oxygen absorber is characterized in that the mass ratio of the mixed powder to the binder in step two is 85-90:10-15. This invention, by controlling the mass ratio of the mixed powder to the binder, ensures that the binder can fully coat the alloy powder, giving the injection-molded green body sufficient strength, while avoiding the drawbacks of the binder being difficult to remove and excessive shrinkage during sintering.

[0016] The above-described method for preparing high-performance injection-molded titanium alloy products by adding an oxygen absorber is characterized in that the oxygen content in the internal mixer chamber during the internal mixing process in step two is less than 800 ppm. This invention, by controlling the oxygen content, prevents material oxidation, ensures the oxygen content of the injection-molded titanium alloy products, and improves their performance.

[0017] The above-mentioned method for preparing high-performance injection-molded titanium alloy products by adding an oxygen absorber is characterized in that, in step three, the mold is preheated at 80℃~120℃ before injection. This invention, by preheating, prevents the material from cooling too quickly when it contacts the mold, thus avoiding defects such as insufficient filling.

[0018] The above-mentioned method for preparing high-performance injection-molded titanium alloy products by adding an oxygen absorber is characterized in that the catalytic degreasing in step four uses oxalic acid with a mass concentration greater than 95%, and the flow rate of oxalic acid in the catalytic degreasing is 3 mL / min to 6 mL / min. This invention, by using oxalic acid with a mass concentration greater than 95% and controlling the flow rate of oxalic acid, accelerates the decomposition of the binder under acidic conditions, fully removing the binder. Compared with nitric acid, oxalic acid degreasing is more environmentally friendly.

[0019] The above-mentioned method for preparing high-performance injection-molded titanium alloy products by adding an oxygen absorber is characterized in that the hot debinding and sintering in step five are carried out under a vacuum degree of no more than 1×10⁻⁶. -2 The process is carried out under conditions of Pa. This invention, by controlling the vacuum level, prevents material oxidation, ensures the oxygen content of the injection-molded titanium alloy products, and improves their performance.

[0020] The above-described method for preparing high-performance injection-molded titanium alloy products by adding an oxygen absorber is characterized in that, in step five, the injection-molded titanium alloy product has a density of not less than 97.4%, and its microstructure is an equiaxed structure with a grain size of less than 70 μm, with Y₂O₃ particles smaller than 2 μm and TiB particles smaller than 8 μm uniformly distributed in the matrix. The injection-molded titanium alloy products prepared by this invention have high density and uniform microstructure; these microstructures and reinforcing phases contribute to the high tensile strength and plasticity of the products.

[0021] Compared with the prior art, the present invention has the following advantages:

[0022] 1. This invention involves thoroughly mixing YB6 powder with titanium alloy spherical powder, followed by intensive mixing and granulation, injection molding, debinding, and sintering. YB6 is used as an oxygen absorber to react with the oxygen in the titanium alloy spherical powder, reducing the oxygen content in the matrix of the injection-molded titanium alloy product. This results in low production costs and the in-situ generation of TiB and Y2O3 reinforcing phases, effectively improving both strength and plasticity simultaneously. This yields high-performance injection-molded titanium alloy products with low oxygen content, high density, and excellent mechanical properties. This invention solves the problem of excessive oxygen content in ultrafine titanium alloy powder used for injection molding and contributes to the development of the titanium and titanium alloy injection molding industry.

[0023] 2. This invention uses ball milling and controlled parameters to ensure thorough and uniform mixing of titanium alloy spherical powder and oxygen absorber YB6 powder. Through intensive mixing and granulation with controlled parameters, the mixed powder and binder are fully integrated to obtain a uniformly dispersed granular feedstock for injection molding of titanium alloy products. Injection molding with controlled parameters shapes the granular feedstock into injection molded titanium alloy green blanks, ensuring good flowability for complete filling and preventing excessive flowability that could cause flash or burrs on the green blank. Catalytic degreasing with controlled parameters removes the binder, and thermal degreasing with controlled parameters ensures complete removal of residual binder. By controlling sintering parameters, densification sintering of the injection-molded parts is achieved.

[0024] 3. In this invention, the yttrium element in the YB6 powder has an extremely strong binding ability with oxygen, forming Y2O3 during sintering. This can significantly reduce the oxygen content in the titanium alloy matrix and break the oxide film on the surface of the titanium alloy spherical powder, thereby improving the powder sintering activity and promoting sintering densification. On the other hand, the boron element in YB6 can generate TiB second phase in situ during sintering, promoting grain refinement, strengthening the matrix, and helping to improve the comprehensive mechanical properties of the titanium alloy.

[0025] 4. By controlling the mass ratio of titanium alloy spherical powder and YB6 powder, this invention ensures that the oxygen absorber can fully react with the oxygen element in the titanium alloy spherical powder, while also preventing the formation of too many brittle phases that would reduce plasticity.

[0026] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0027] Figure 1 This is a scanning electron microscope image of the Ti-6Al-4V spherical powder used in Example 1 of the present invention.

[0028] Figure 2 This is a scanning electron microscope image of the YB6 powder used in Example 1 of the present invention.

[0029] Figure 3 This is a microstructure image of the injection-molded titanium alloy tensile test bar prepared in Example 1 of the present invention. Detailed Implementation

[0030] Example 1

[0031] This embodiment includes the following steps:

[0032] Step 1: Powder mixing: TC4 (Ti-6Al-4V) spherical powder with a particle size of less than 25 μm and an oxygen content of 0.17 wt.% and YB6 powder with a particle size of less than 10 μm are added to a ball mill jar at a mass ratio of 99.6:0.4 and argon gas is introduced for protection. The mixture is then mixed evenly using a ball mill at a speed of 200 rpm, a ball-to-powder ratio of 5:1, and a milling time of 3 hours. The resulting mixed powder is then sealed and stored.

[0033] Step 2, Internal Mixing and Granulation: The mixed powder obtained in Step 1 and the binder are added to an internal mixer at a mass ratio of 90:10 and mixed under argon protection. The oxygen content in the internal mixer chamber is less than 600 ppm, the mixing temperature is 180℃, the rotation speed is 35 rpm, and the time is 1 hour to obtain a mixture. The mixture is then granulated by a granulator to obtain granular feedstock for injection molding titanium alloy products. The binder is composed of the following components by mass fraction: 82% polyoxymethylene, 6% high-density polyethylene, 5% ethylene-vinyl acetate copolymer, 5% stearic acid, and 2% hyperbranched polyamide resin.

[0034] Step 3, Injection Molding: The granular injection-molded titanium alloy product obtained in Step 2 is fed into the hopper of the injection molding machine. The mold is preheated at 100°C and then injected into the mold. The injection pressure is 120MPa, the injection temperature is 180°C, the injection speed is 150mm / s, and the cooling time is 10s to obtain the injection-molded titanium alloy product blank.

[0035] Step 4, Catalytic Degreasing: The injection-molded titanium alloy blank obtained in Step 3 is placed in an oxalic acid degreasing furnace for catalytic degreasing. The catalytic degreasing uses oxalic acid with a mass concentration greater than 95%, and the flow rate of oxalic acid is 4 mL / min. The temperature of catalytic degreasing is 130℃ and the time is 10 h to obtain a degreased blank.

[0036] Step 5, Hot Degreasing and Sintering: Place the degreased blank obtained in Step 4 into a vacuum sintering furnace with a molybdenum heating element. When the vacuum degree reaches 1×10⁻⁶, heat the blank until it reaches a solid temperature of 10⁻⁶. -3 Pa starts heating up to 550℃ at a rate of 2℃ / min, holds for 4 hours for hot degreasing, then heats up to 1300℃ at a rate of 5℃ / min, holds for 2 hours for sintering, and cools to room temperature with the furnace to obtain injection-molded titanium alloy tensile test bars.

[0037] Testing revealed that the microstructure of the injection-molded titanium alloy tensile test bar prepared in this embodiment was an equiaxed structure with a grain size of less than 70 μm. Y2O3 particles smaller than 2 μm and TiB particles smaller than 8 μm were uniformly distributed in the α matrix. The room temperature tensile elongation at break of the tensile test bar reached 6.5%, the tensile strength reached 980 MPa, and the density reached 98.0%.

[0038] Figure 1 This is a scanning electron microscope (SEM) image of the Ti-6Al-4V spherical powder used in this embodiment. Figure 1 As can be seen, the Ti-6Al-4V spherical powder has a particle size of less than 25μm, high sphericity, few satellite spheres, and good surface quality.

[0039] Figure 2 Here is a scanning electron microscope (SEM) image of the YB6 powder used in this embodiment. Figure 2 As can be seen, YB6 powder is an irregular powder with a particle size of less than 15μm.

[0040] Figure 3 This is a microstructure image of the injection-molded titanium alloy tensile test bar prepared in this embodiment. Figure 3 As can be seen, the microstructure of the injection-molded titanium alloy product is an equiaxed structure with a grain size of less than 70 μm, and Y2O3 particles smaller than 2 μm and TiB particles smaller than 8 μm are uniformly distributed in the matrix.

[0041] Comparative Example 1

[0042] The difference between this comparative example and Example 1 is that YB6 powder is not added.

[0043] Testing revealed that the room temperature tensile elongation at break of the injection-molded titanium alloy product tensile test bar prepared in this comparative example was only 4.0%, the tensile strength was only 935 MPa, and the density was 96.8%.

[0044] A comparison between Example 1 and Comparative Example 1 shows that the tensile properties and density of the injection-molded titanium alloy tensile test bar obtained by adding YB6 as an oxygen absorber in Example 1 are significantly higher than those obtained in Comparative Example 1 without adding an oxygen absorber. This indicates that adding an oxygen absorber can significantly improve the strength, plasticity, and density of the injection-molded titanium alloy tensile test bar.

[0045] Example 2

[0046] This embodiment includes the following steps:

[0047] Step 1, Powder Mixing: Add TA1 spherical powder with a particle size of less than 25 μm and an oxygen content of 0.14 wt.% and YB6 powder with a particle size of less than 10 μm to a ball mill jar at a mass ratio of 99.8:0.2, and purge with argon gas for protection. Mix evenly using a ball mill at a speed of 150 rpm, a ball-to-powder ratio of 7:1, and a milling time of 4 hours. Obtain the mixed powder and seal it for storage.

[0048] Step 2, Internal Mixing and Granulation: The mixed powder obtained in Step 1 and the binder are added to an internal mixer at a mass ratio of 88:12 and mixed under argon protection. The oxygen content in the internal mixer chamber is less than 700 ppm, the mixing temperature is 170℃, the rotation speed is 40 rpm, and the time is 3 hours to obtain a mixture. The mixture is then granulated by a granulator to obtain granular feedstock for injection molding titanium alloy products. The binder is composed of the following components by mass fraction: 80% polyoxymethylene, 8% high-density polyethylene, 6% ethylene-vinyl acetate copolymer, 3% stearic acid, and 3% hyperbranched polyamide resin.

[0049] Step 3, Injection Molding: The granular injection-molded titanium alloy product obtained in Step 2 is fed into the hopper of the injection molding machine. The mold is preheated at 80°C and then injected into the mold. The injection pressure is 200MPa, the injection temperature is 170°C, the injection speed is 180mm / s, and the cooling time is 5s to obtain the injection-molded titanium alloy product blank.

[0050] Step 4, Catalytic Degreasing: The injection-molded titanium alloy blank obtained in Step 3 is placed in an oxalic acid degreasing furnace for catalytic degreasing. The catalytic degreasing uses oxalic acid with a mass concentration greater than 95%, and the flow rate of oxalic acid is 3 mL / min. The temperature of catalytic degreasing is 120℃ and the time is 12 h to obtain a degreased blank.

[0051] Step 5, Hot Degreasing and Sintering: Place the degreased blank obtained in Step 4 into a vacuum sintering furnace with a molybdenum heating element. When the vacuum degree reaches 1×10⁻⁶, heat the blank until it reaches a solid temperature of 10⁻⁶. -3 The temperature is initially raised to 500℃ at a rate of 1℃ / min and held for 6 hours for hot degreasing. Then, the temperature is raised to 1250℃ at a rate of 7℃ / min and held for 3 hours for sintering. The product is then cooled to room temperature in the furnace to obtain the injection-molded titanium alloy product.

[0052] Testing revealed that the microstructure of the injection-molded titanium alloy product prepared in this embodiment was an equiaxed structure with a grain size of less than 70 μm. Y2O3 particles smaller than 2 μm and TiB particles smaller than 8 μm were uniformly distributed in the α matrix. The room temperature tensile elongation at break of the tensile test bar reached 10.0%, the tensile strength reached 490 MPa, and the density reached 97.4%.

[0053] Example 3

[0054] This embodiment includes the following steps:

[0055] Step 1: Powder Mixing: TC18 (Ti-5Al-5Mo-5V-1Cr-1Fe) spherical powder with a particle size of less than 25μm and an oxygen content of 0.18wt.% and YB6 powder with a particle size of less than 10μm are added to a ball mill jar at a mass ratio of 99.4:0.6 and argon gas is introduced for protection. The mixture is then mixed evenly using a ball mill at a speed of 300rpm, a ball-to-powder ratio of 4:1, and a milling time of 2h. The resulting mixed powder is then sealed and stored.

[0056] Step 2, Internal Mixing and Granulation: The mixed powder obtained in Step 1 and the binder are added to an internal mixer at a mass ratio of 85:15 and mixed under argon protection. The oxygen content in the internal mixer chamber is less than 500 ppm, the mixing temperature is 190℃, the rotation speed is 30 rpm, and the time is 2 hours to obtain a mixture. The mixture is then granulated by a granulator to obtain granular feedstock for injection molding titanium alloy products. The binder is composed of the following components by mass fraction: 85% polyoxymethylene, 5% high-density polyethylene, 8% ethylene-vinyl acetate copolymer, 1% stearic acid, and 1% hyperbranched polyamide resin.

[0057] Step 3, Injection Molding: The granular injection-molded titanium alloy product obtained in Step 2 is fed into the hopper of the injection molding machine. The mold is preheated at 120°C and then injected into the mold. The injection pressure is 100MPa, the injection temperature is 190°C, the injection speed is 140mm / s, and the cooling time is 8s to obtain the injection-molded titanium alloy product blank.

[0058] Step 4, Catalytic Degreasing: The injection-molded titanium alloy blank obtained in Step 3 is placed in an oxalic acid degreasing furnace for catalytic degreasing. The catalytic degreasing uses oxalic acid with a mass concentration greater than 95%, and the flow rate of oxalic acid is 6 mL / min. The temperature of catalytic degreasing is 110℃ and the time is 8 hours to obtain a degreased blank.

[0059] Step 5, Hot Degreasing and Sintering: Place the degreased blank obtained in Step 4 into a vacuum sintering furnace with a molybdenum heating element. When the vacuum degree reaches 1×10⁻⁶, heat the blank until it reaches a solid temperature of 10⁻⁶. -3 The temperature is initially raised to 600℃ at a rate of 3℃ / min, held for 3 hours for hot degreasing, and then raised to 1200℃ at a rate of 6℃ / min, held for 4 hours for sintering. The product is then cooled to room temperature in the furnace to obtain the injection-molded titanium alloy product.

[0060] Testing revealed that the microstructure of the injection-molded titanium alloy product prepared in this embodiment was an equiaxed structure with a grain size of less than 70 μm. Y2O3 particles smaller than 2 μm and TiB particles smaller than 8 μm were uniformly distributed in the α matrix. The room temperature tensile elongation at break of the tensile test bar reached 5.5%, the tensile strength reached 1100 MPa, and the density reached 97.5%.

[0061] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any way. Any simple modifications, alterations, and equivalent changes made to the above embodiments based on the technical essence of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A method for preparing high-performance injection-molded titanium alloy products by adding an oxygen absorber, characterized in that, The method includes the following steps: Step 1: Powder Mixing: Add titanium alloy spherical powder and YB6 powder to a ball mill jar, and purge with argon gas for protection. Then, use a ball mill to mix them evenly to obtain a mixed powder. The ball mill speed is 150 rpm to 300 rpm, the ball-to-powder ratio is 4 to 7:1, and the milling time is 2 to 4 hours. The mass ratio of titanium alloy spherical powder to YB6 powder in the mixed powder is 99.4 to 99.8: 0.2 to 0.

6. Step 2, Intensive Mixing and Granulation: The mixed powder obtained in Step 1 is mixed with the binder, and then subjected to intensive mixing under argon protection to obtain a mixture. The mixture is then granulated to obtain granular feedstock for injection molding titanium alloy products. The intensive mixing process is carried out at a temperature of 170℃~190℃, a rotation speed of 30rpm~40rpm, and a time of 1h~3h. Step 3, Injection Molding: The granular injection-molded titanium alloy product obtained in Step 2 is fed into the hopper of the injection molding machine, then injected into the mold, and then cooled to obtain the injection-molded titanium alloy product blank; the injection pressure is 100MPa~200MPa, the injection temperature is 170℃~190℃, the injection speed is 140mm / s~180mm / s, and the cooling time is 5s~10s; Step 4, Catalytic Degreasing: The injection-molded titanium alloy blank obtained in Step 3 is placed in an oxalic acid degreasing furnace for catalytic degreasing to obtain a degreased blank; the temperature of the catalytic degreasing is 110℃~130℃, and the time is 8h~12h. Step 5, Hot Degreasing and Sintering: The degreased blank obtained in Step 4 is placed in a vacuum sintering furnace with a molybdenum heating element and heated to 500℃~600℃ at a heating rate of 1℃ / min~3℃ / min, held for 3h~6h for hot degreasing, and then heated to 1200℃~1300℃ at a heating rate of 5℃ / min~7℃ / min, held for 2h~4h for sintering to obtain injection-molded titanium alloy products; the microstructure of the injection-molded titanium alloy products is an equiaxed structure with a grain size of less than 70μm, and Y2O3 particles smaller than 2μm and TiB particles smaller than 8μm are uniformly distributed in the matrix.

2. The method for preparing high-performance injection-molded titanium alloy products by adding an oxygen absorber according to claim 1, characterized in that, The titanium alloy spherical powder mentioned in step one is made of TA1, TC18 or TC4, and the particle size of the titanium or titanium alloy spherical powder satisfies D90≤30μm, and the particle size of the YB6 powder is not greater than 20μm.

3. The method for preparing high-performance injection-molded titanium alloy products by adding an oxygen absorber according to claim 1, characterized in that, The adhesive mentioned in step two is a polyoxymethylene-based system, composed of the following components by mass fraction: 80%~85% polyoxymethylene, 5%~8% high-density polyethylene, 5%~8% ethylene-vinyl acetate copolymer, 1%~5% stearic acid and 1%~3% hyperbranched polyamide resin.

4. The method for preparing high-performance injection-molded titanium alloy products by adding an oxygen absorber according to claim 1, characterized in that, The mass ratio of the mixed powder to the binder in step two is 85~90:10~15.

5. The method for preparing high-performance injection-molded titanium alloy products by adding an oxygen absorber according to claim 1, characterized in that, In step two, the oxygen content inside the mixing chamber of the mixing machine is less than 800 ppm.

6. The method for preparing high-performance injection-molded titanium alloy products by adding an oxygen absorber according to claim 1, characterized in that, In step three, the mold is preheated at 80℃~120℃ before injection.

7. The method for preparing high-performance injection-molded titanium alloy products by adding an oxygen absorber according to claim 1, characterized in that, The catalytic degreasing in step four uses oxalic acid with a mass concentration greater than 95%, and the flow rate of oxalic acid in the catalytic degreasing is 3 mL / min to 6 mL / min.

8. The method for preparing high-performance injection-molded titanium alloy products by adding an oxygen absorber according to claim 1, characterized in that, The thermal degreasing and sintering described in step five are performed under a vacuum degree not exceeding 1×10⁻⁶. -2 The experiment was conducted under the condition of Pa.

9. The method for preparing high-performance injection-molded titanium alloy products by adding an oxygen absorber according to claim 1, characterized in that, The density of the injection-molded titanium alloy product described in step five is not less than 97.4%.

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