A method for improving the strength of additively manufactured titanium alloys

Abstract

The present invention discloses a method for improving the strength of additively manufactured titanium alloy. The method includes: First, adding tungsten powder to Ti185 alloy powder to obtain mixed powder; Second, using the mixed powder as raw material, adopting a powder bed electron beam additive manufacturing forming device, and through controlling the forming parameters, obtaining a strengthened titanium alloy with equiaxed grains inside. By adding tungsten powder to the titanium alloy powder, the present invention introduces nucleation sites, improves the growth restriction factor value of the alloy, reduces the average energy level Md value of the d orbitals of transition elements, and increases the covalent bond strength Bo value. Prepared by the powder bed electron beam additive manufacturing technology, it avoids composition segregation in the alloy, promotes the precipitation of nano-α strengthening phases, makes the tensile strength of the finally prepared titanium alloy higher than 1355 MPa, the yield strength higher than 1253 MPa, the elongation after fracture higher than 5%, with excellent tensile properties, can be made into high-performance components, and has a wide range of applications.

Description

Technical Field

[0001] The present invention belongs to the technical field of alloy material preparation, and particularly relates to a method for improving the strength of additively manufactured titanium alloy. Background Art

[0002] Titanium alloy has the advantages of high specific strength, good biocompatibility, corrosion resistance, non-magnetism, heat resistance, etc., and has been widely used in the fields of biomedicine, aerospace, ocean engineering, petrochemical industry, etc. With the rapid development of the aerospace industry, conventional titanium alloy materials are difficult to meet its requirements, so high-strength titanium alloys have come into people's sight.

[0003] Titanium alloy has poor thermal conductivity, large deformation resistance, narrow forging temperature range, high affinity for oxygen, etc., which makes the preparation of titanium alloy samples have many difficulties. Powder bed electron beam additive manufacturing, also known as electron beam selective melting (SEBM), is an advanced manufacturing technology developed in the 1990s, which has the advantages of fast scanning speed, pollution-free high-vacuum environment, low residual stress, etc., and is particularly suitable for the direct forming of reactive metal materials such as titanium alloy.

[0004] Ti-1Al-8V-5Fe (abbreviated as Ti185) alloy belongs to metastable β titanium alloy, which has high tensile strength and shear strength, and is widely used in aerospace fasteners and some parts with high strength requirements. In addition, compared with other metastable β titanium alloys, this alloy has lower cost. This alloy generally adopts the method of solution aging treatment to precipitate nano-α phase for strengthening, but the complex thin-walled parts of this alloy are prone to deformation after solution aging treatment. The bottom plate preheating temperature of the powder bed electron beam additive manufacturing technology is as high as 1000°C, and the forming process is coupled with solution aging, which can realize the direct forming of Ti185 complex thin-walled parts. However, the Ti185 alloy formed by the powder bed electron beam additive manufacturing technology has a coarse columnar crystal structure along the forming direction, and the intragranular is micron-sized α phase, and the strengthening effect is not ideal, which limits the wide application of this alloy. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a method for improving the strength of additively manufactured titanium alloy aiming at the deficiencies of the above-mentioned prior art. This method adds tungsten powder to the Ti185 alloy powder, introduces nucleation sites while increasing the growth restriction factor value of the alloy, reduces the Md value and increases the Bo value, and uses the powder bed electron beam additive manufacturing technology to prepare, avoiding the composition segregation of titanium alloy, promoting the precipitation of nano-α strengthening phase, making the finally prepared titanium alloy have excellent tensile properties and improving the strength of additively manufactured titanium alloy.

[0006] To solve the above technical problem, the technical solution adopted by the present invention is: a method for improving the strength of additively manufactured titanium alloy, characterized in that the method comprises the following steps:

[0007] Step 1: Add tungsten powder to the spherical Ti185 alloy powder prepared by plasma rotating electrode gas atomization, and then mix them using a planetary ball mill to obtain a mixed powder.

[0008] Step 2: Draw a three-dimensional model of the target product, and then cut it into equal-thickness slices along its height direction for layering treatment to obtain sliced data. Then, design the internal scanning method and scanning path for each slice to obtain sliced scanning data.

[0009] Step 3: Import the sliced data and sliced scanning data obtained in Step 2 into a powder bed electron beam additive manufacturing forming device. Load the mixed powder obtained in Step 1 into the powder box of the powder bed electron beam additive manufacturing forming device, and then level the forming base plate of the powder bed electron beam additive manufacturing forming device and preheat the forming base plate; the preheating temperature of the forming base plate is 700°C to 720°C.

[0010] Step 4: Lay the mixed powder loaded in the powder box in Step 3 on the preheated forming base plate to form a powder layer, and then preheat the powder layer; the preheating temperature of the powder layer is 700°C to 720°C, and the thickness of the laid mixed powder is the same as the thickness of each slice in Step 2.

[0011] Step 5: According to the sliced data and sliced scanning data imported into the powder bed electron beam additive manufacturing forming device in Step 2, use an electron beam to melt and scan the preheated powder layer in Step 4 to form a single-layer solid slice, and then lower the forming base plate; the height by which the forming base plate is lowered is the same as the thickness of each slice in Step 2.

[0012] Step 6: Repeat Step 4 and Step 5 until each single-layer solid slice is stacked layer by layer to form a powder bed electron beam additive manufacturing formed part. Then, take it out when the temperature of the forming base plate is less than 100°C, and use high-pressure gas to remove the residual powder on the surface of the powder bed electron beam additive manufacturing formed part to obtain a reinforced titanium alloy; the tensile strength of the reinforced titanium alloy is higher than 1355 MPa, the tensile yield strength is higher than 1253 MPa, and the elongation after fracture is higher than 5%.

[0013] In the present invention, a planetary ball mill is used to mix the Ti185 alloy powder and tungsten powder prepared by plasma rotating electrode gas atomization. The Ti185 alloy powder prepared by plasma rotating electrode atomization has a high sphericity and a particle size suitable for powder bed electron beam additive manufacturing technology. Using this spherical powder is easy to spread evenly, which is beneficial to improving the tissue uniformity of the Ti185 alloy. The melting point of tungsten is 3422°C, and the melting point of Ti185 is about 1500°C. The difference in melting points between the two exceeds 1500°C. The energy density of tungsten in powder bed electron beam additive manufacturing is 1440 J / mm 3 ~3840 J / mm 3, while the energy density of the Ti185 alloy manufactured by powder bed electron beam additive manufacturing is 27 J / mm 3 ~30 J / mm 3 , with the forming parameters of the Ti185 alloy manufactured by powder bed electron beam additive manufacturing, the tungsten powder doped on the surface of the Ti185 alloy powder cannot be completely melted, and the unmelted tungsten powder can play the role of heterogeneous nucleation. In addition, for every 1 wt.% of tungsten contained in the titanium alloy, the growth restriction factor Q can increase by 22.7. According to the interdependence theory of alloy solidification, the existence of nucleation particles and a high Q value is conducive to realizing the transformation from coarse columnar grains to fine equiaxed grains and achieving grain refinement. Through grain refinement strengthening, the strength of the titanium alloy is improved. Finally, according to the d-electron theory of alloy composition design, tungsten can increase the covalent bond strength Bo value of the Ti185 alloy and reduce the average energy level Md value of the d orbit of transition elements. The lower the Md value, the more stable the phase, and the greater the Bo value, the higher the alloy performance. In addition, tungsten is a β-stable element, and the addition of tungsten can reduce the β / α transformation temperature. When preparing this alloy by powder bed electron beam additive manufacturing technology, it is conducive to the alloy obtaining finer strengthening phase α; in the present invention, a planetary ball mill is used to mix the Ti185 alloy powder and tungsten powder, which is conducive to the uniform distribution of tungsten powder on the surface of the Ti185 alloy powder, and thus is conducive to improving the composition uniformity of the alloy. When preparing the titanium alloy by powder bed electron beam additive manufacturing technology, by preheating the spherical titanium alloy powder and the forming bottom plate and controlling the preheating temperature at 700°C to 720°C, each layer of the prepared titanium alloy has undergone repeated heat treatment processes, gradually releasing the internal thermal stress of the titanium alloy, and thus making the internal structure of the titanium alloy tend to be uniform. At the same time, the spherical titanium alloy powder is preheated and then melted and scanned. Preheating is conducive to the adhesion of elements in the titanium alloy, avoiding movement caused by electron beam impact, improving the interlayer bonding force of the titanium alloy, and also conducive to avoiding composition segregation in the prepared titanium alloy, especially the segregation of Fe element to produce β-spot defects, which affect the strength of the titanium alloy.

[0014] The above method for improving the strength of additively manufactured titanium alloy is characterized in that the spherical Ti185 alloy powder in step one is composed of the following components by mass content: Al 1.38%, V 8.00%, Fe 4.22%, O 0.19%, and the balance is titanium and unavoidable impurities. The particle size of the spherical Ti185 alloy powder is 40 μm to 150 μm. The present invention controls the composition and particle size of the spherical Ti185 alloy powder, so that the spherical Ti185 alloy powder has good fluidity, which is conducive to the spreading of the spherical Ti185 alloy powder on the forming bottom plate, improving the uniformity of the laid powder layer, and further improving the uniformity of each component in the Ti185 alloy, avoiding the occurrence of composition segregation phenomenon. At the same time, the spherical Ti185 alloy powder with the above particle size is conducive to improving the melting speed in the forming process of powder bed electron beam additive manufacturing.

[0015] The above method for improving the strength of additively manufactured titanium alloy is characterized in that, in step one, the particle size of the tungsten powder is 1 μm to 10 μm, and the mass of the tungsten powder in the mixed powder is 5% to 15% of the mass of the Ti185 alloy powder. In the present invention, the content of tungsten is controlled at 5% to 15% for two reasons: firstly, if the content of tungsten is less, it cannot play the role of heterogeneous nucleation; secondly, if the content of tungsten is higher, the unfused area of the alloy is larger, and a large number of defects will be generated in the alloy, which will instead reduce the strength of the alloy.

[0016] The above method for improving the strength of additively manufactured titanium alloy is characterized in that, in step one, the rotation speed of the planetary ball mill in the mixing is 10 r / min to 30 r / min, and the time is 3 h to 5 h. In the present invention, the mixed powder is put into the ball milling tank, and an appropriate amount of ball milling beads and alcohol are put into the tank. By controlling the ball milling parameters, it is beneficial for the tungsten powder to adhere to the surface of the Ti185 alloy powder more uniformly and without agglomeration. Adding alcohol during the ball milling process can also promote the tungsten powder to adhere to the surface of the Ti185 alloy powder more uniformly.

[0017] The above method for improving the strength of additively manufactured titanium alloy is characterized in that, in step two, the thickness of the layer is 0.05 mm to 0.1 mm. The layer thickness is the powder spreading thickness. In the present invention, the layer thickness is set at 0.05 mm to 0.1 mm to adapt to the melting ability of the electron beam for the spherical titanium alloy powder.

[0018] The above method for improving the strength of additively manufactured titanium alloy is characterized in that, in step five, the process parameters of the melting scan are: the scan line spacing is 0.05 mm to 0.1 mm, the scan current is 6 mA to 15 mA, and the scan speed is 1400 mm / s to 3000 mm / s. In the present invention, the above forming parameters are used for powder bed electron beam additive manufacturing of titanium alloy for spherical titanium alloy powder, effectively controlling the dimensional accuracy and melting quality of each layer during the forming process, making the prepared titanium alloy formed part uniform inside and complete in shape, which is beneficial to improving the strength of the titanium alloy.

[0019] The present invention has the following advantages compared with the prior art:

[0020] 1. In the present invention, tungsten is added as a heterogeneous nucleating agent and grain refiner to the additively manufactured titanium alloy, introducing nucleation sites while increasing the growth restriction factor value of the alloy, reducing the Md value and increasing the Bo value, refining the grains of the additively manufactured titanium alloy, and thus improving the alloy strength.

[0021] 2. The present invention uses the powder bed electron beam additive manufacturing technology to prepare titanium alloy. By preheating the spherical titanium alloy powder and the forming base plate and controlling the preheating temperature at 700°C to 720°C, each layer of the prepared titanium alloy undergoes a repeated heat treatment process, gradually releasing the internal thermal stress of the titanium alloy, and thus making the internal structure of the titanium alloy tend to be uniform. At the same time, the spherical titanium alloy powder is preheated and then melted and scanned. Preheating is beneficial for the elements in the titanium alloy to adhere, avoiding movement caused by electron beam impact, improving the interlayer bonding force of the titanium alloy, and also helping to avoid composition segregation in the prepared titanium alloy, especially the segregation of Fe element to produce β - spot defects, which affect the strength of the titanium alloy.

[0022] 3. By controlling the tungsten content and using the powder bed electron beam additive manufacturing technology, the finally prepared reinforced titanium alloy has equiaxed crystals inside and high strength. Its tensile strength is higher than 1355 MPa, yield strength is higher than 1253 MPa, and elongation after fracture is higher than 5%. It can be made into high - strength components and has a wide range of applications.

[0023] The technical solution of the present invention will be further described in detail below with reference to the drawings and embodiments. Description of the Drawings

[0024] Figure 1 is the optical microscope image of the reinforced titanium alloy prepared in Example 1 of the present invention.

[0025] Figure 2 is the optical microscope image of the titanium alloy prepared in Comparative Example 1 of the present invention. Detailed Embodiments

[0026] Example 1

[0027] This example includes the following steps:

[0028] Step 1: Add tungsten powder to the spherical Ti185 alloy powder prepared by plasma rotating electrode gas atomization, then add an appropriate amount of ball - milling beads and alcohol, and then use a planetary ball mill to mix at a speed of 20 r / min for 4 h to obtain a mixed powder. The spherical Ti185 alloy powder is composed of the following components by mass content: Al 1.38%, V 8.00%, Fe 4.22%, O 0.19%, and the balance is titanium and inevitable impurities. The particle size of the spherical Ti185 alloy powder is 40 μm to 150 μm; the particle size of the tungsten powder is 1 μm to 10 μm; the mass of the tungsten powder in the mixed powder is 10% of the mass of the Ti185 alloy powder.

[0029] Step 2: Use Magics software to draw the 3D model of the target product. The model size is 80mm×13mm×22mm (length×width×height). Then, cut it into equal-thickness slices along its height direction for layer-by-layer processing to obtain sliced data. Next, design the internal scanning method and scanning path for each slice to obtain sliced scanning data. The thickness of each slice is 0.1mm;

[0030] Step 3: Import the sliced data and sliced scanning data obtained in Step 2 into a powder bed electron beam additive manufacturing forming device. Load the mixed powder obtained in Step 1 into the powder box of the powder bed electron beam additive manufacturing forming device. Then, level the forming bottom plate of the powder bed electron beam additive manufacturing forming device and preheat the forming bottom plate. The preheating temperature of the forming bottom plate is 720°C. The model of the forming device is the Cailong Y150 type. The size of the forming bottom plate is 100mm×100mm×10mm (length×width×thickness);

[0031] Step 4: Lay the mixed powder loaded into the powder box in Step 3 on the preheated forming bottom plate to form a powder layer, and then preheat the powder layer. The preheating temperature of the powder layer is 720°C. The laying thickness of the mixed powder is the same as the thickness of each slice in Step 2;

[0032] Step 5: According to the sliced data and sliced scanning data imported into the powder bed electron beam additive manufacturing forming device in Step 2, use an electron beam to melt and scan the preheated powder layer in Step 4 to form a single-layer solid slice. Then, lower the forming bottom plate. The lowering height of the forming bottom plate is the same as the thickness of each slice in Step 2. The process parameters of the melting scan are: the scanning line spacing is 0.1mm, the scanning current is 15mA, and the scanning speed is 3000mm / s;

[0033] Step 6: Repeat Step 4 and Step 5 until each single-layer solid slice is stacked layer by layer to form a powder bed electron beam additive manufacturing formed part. Then, take it out when the temperature of the forming bottom plate is less than 100°C, and use high-pressure gas to remove the residual powder on the surface of the powder bed electron beam additive manufacturing formed part to obtain the reinforced titanium alloy.

[0034] After testing, the tensile strength of the reinforced titanium alloy prepared in this example is 1446.25MPa, the yield strength is 1341.43MPa, and the elongation after fracture is 5.34%.

[0035] Figure 1 is the optical microscope image of the reinforced titanium alloy prepared in this example. From Figure 1 it can be seen that there are unmelted tungsten powders on the reinforced titanium alloy prepared in this example, which play a role in heterogeneous nucleation, resulting in the appearance of equiaxed grains. The equiaxed grains are along the forming direction, and the inside is fine α.

[0036] Comparative Example 1

[0037] The difference between this comparative example and Example 1 is that: in this comparative example, tungsten powder was not added to the Ti185 alloy powder to obtain a titanium alloy.

[0038] After testing, the tensile strength of the titanium alloy specimen prepared in this comparative example was 1075 MPa, the yield strength was 1005 MPa, and the elongation after fracture was 17%.

[0039] Figure 2 is the optical microscope image of the titanium alloy prepared in this comparative example. It can be seen from Figure 2 that the titanium alloy prepared in this comparative example is columnar crystal along the forming direction.

[0040] It can be seen from the comparison between Example 1 and Comparative Example 1 that without doping tungsten powder into the Ti185 alloy powder, the growth restriction factor value of the Ti185 alloy is relatively low. After calculation, the growth restriction factor of the Ti185 alloy is 46.8. When 10% tungsten powder is added to the Ti185 alloy powder to form a mixed titanium alloy powder, the growth restriction factor of this titanium alloy (the tungsten content in the detected powder bed electron beam 3D printed Ti185+W alloy is 3.5%) is 126.25. In addition, there are still unmelted tungsten powders in the alloy. According to the theory of mutual dependence of solidification, there are nucleation sites, and the higher the growth restriction factor value, the easier it is to form equiaxed crystals. The enhanced titanium alloy obtained in Example 1 has equiaxed crystals inside, while the titanium alloy obtained in Comparative Example 1 has columnar crystals inside. The grain size and intragranular strengthening phase size of the equiaxed crystals are smaller than those of the corresponding columnar crystals, resulting in the former having higher strength than the latter.

[0041] Example 2

[0042] This example includes the following steps:

[0043] Step 1: Add 100 g of tungsten powder to 1 kg of spherical Ti185 alloy powder prepared by plasma rotating electrode gas atomization. Then add an appropriate amount of ball milling beads and alcohol, and then use a planetary ball mill to mix at a speed of 10 r / min for 5 h to obtain a mixed powder; the spherical Ti185 alloy powder is composed of the following components by mass content: Al 1.38%, V 8.00%, Fe 4.22%, O 0.19%, and the balance is titanium and inevitable impurities. The particle size of the spherical Ti185 alloy powder is 40 μm - 150 μm; the particle size of the tungsten powder is 1 μm - 10 μm; the mass of the tungsten powder in the mixed powder is 5% of the mass of the Ti185 alloy powder;

[0044] Step 2: Use Magics software to draw a 3D model of the target product with a model size of 80 mm × 13 mm × 22 mm (length × width × height). Then, cut it into slices of equal thickness along its height direction for layer-by-layer processing to obtain sliced data. Next, design the internal scanning method and scanning path for each slice to obtain sliced scanning data. The thickness of each slice is 0.08 mm.

[0045] Step 3: Import the sliced data and sliced scanning data obtained in Step 2 into a powder bed electron beam additive manufacturing forming device. Load the mixed powder obtained in Step 1 into the powder box of the powder bed electron beam additive manufacturing forming device. Then, level the forming base plate of the powder bed electron beam additive manufacturing forming device and preheat the forming base plate. The preheating temperature of the forming base plate is 710 °C. The model of the forming device is the Sylon Y150 type. The size of the forming base plate is 100 mm × 100 mm × 10 mm (length × width × thickness).

[0046] Step 4: Lay the mixed powder loaded into the powder box in Step 3 on the preheated forming base plate to form a powder layer. Then, preheat the powder layer. The preheating temperature of the powder layer is 710 °C. The thickness of the laid mixed powder is the same as the thickness of each slice in Step 2.

[0047] Step 5: According to the sliced data and sliced scanning data imported into the powder bed electron beam additive manufacturing forming device in Step 2, use an electron beam to melt and scan the preheated powder layer in Step 4 to form a single-layer solid slice. Then, lower the forming base plate. The height by which the forming base plate is lowered is the same as the thickness of each slice in Step 2. The process parameters for the melting scan are: the scanning line spacing is 0.05 mm, the scanning current is 6 mA, and the scanning speed is 1400 mm / s.

[0048] Step 6: Repeat Step 4 and Step 5 until each single-layer solid slice is stacked layer by layer to form a powder bed electron beam additive manufacturing formed part. Then, take it out when the temperature of the forming base plate is less than 100 °C, and use high-pressure gas to remove the residual powder on the surface of the powder bed electron beam additive manufacturing formed part to obtain a reinforced titanium alloy.

[0049] After testing, the tensile strength of the reinforced titanium alloy prepared in this example is 1396.66 MPa, the yield strength is 1293.59 MPa, and the elongation after fracture is 7.7%.

[0050] Example 3

[0051] This example includes the following steps:

[0052] Step 1: Add 100 g of tungsten powder to 1 kg of spherical Ti185 alloy powder prepared by plasma rotating electrode gas atomization. Then add an appropriate amount of ball milling beads and alcohol, and then use a planetary ball mill to mix at a speed of 30 r / min for 3 h to obtain a mixed powder. The spherical Ti185 alloy powder is composed of the following components by mass content: Al 1.38%, V 8.00%, Fe 4.22%, O 0.19%, and the balance is titanium and inevitable impurities. The particle size of the spherical Ti185 alloy powder is 40 μm to 150 μm; the particle size of the tungsten powder is 1 μm to 10 μm; the mass of the tungsten powder in the mixed powder is 15% of the mass of the Ti185 alloy powder.

[0053] Step 2: Use Magics software to draw a three-dimensional model of the target product. The model size is 80 mm × 13 mm × 22 mm (length × width × height). Then cut it into equal-thickness slices along its height direction for layer-by-layer processing to obtain sliced data. Then design the internal scanning method and scanning path for each slice to obtain sliced scanning data. The thickness of the slice is 0.05 mm.

[0054] Step 3: Import the sliced data and sliced scanning data obtained in Step 2 into a powder bed electron beam additive manufacturing forming device. Load the mixed powder obtained in Step 1 into the powder box of the powder bed electron beam additive manufacturing forming device, and then level the forming bottom plate of the powder bed electron beam additive manufacturing forming device and preheat the forming bottom plate. The preheating temperature of the forming bottom plate is 700°C; the model of the forming device is the Sailong Y150 type; the size of the forming bottom plate is 100 mm × 100 mm × 10 mm (length × width × thickness).

[0055] Step 4: Lay the mixed powder loaded in the powder box in Step 3 on the preheated forming bottom plate to form a powder layer, and then preheat the powder layer. The preheating temperature of the powder layer is 700°C, and the thickness of the laid mixed powder is the same as the thickness of each slice in Step 2.

[0056] Step 5: According to the sliced data and sliced scanning data imported into the powder bed electron beam additive manufacturing forming device in Step 2, use an electron beam to melt and scan the preheated powder layer in Step 4 to form a single-layer solid slice, and then lower the forming bottom plate. The height of the lowered forming bottom plate is the same as the thickness of each slice in Step 2. The process parameters of the melting scan are: the scanning line spacing is 0.08 mm, the scanning current is 10 mA, and the scanning speed is 2200 mm / s.

[0057] Step Six: Repeat Step Four and Step Five until each single-layer solid sheet is stacked layer by layer to form a powder bed electron beam additive manufacturing part. Then, take it out when the temperature of the bottom plate to be formed is less than 100°C, and use high-pressure gas to remove the residual powder on the surface of the powder bed electron beam additive manufacturing part to obtain the reinforced titanium alloy.

[0058] After testing, the tensile strength of the reinforced titanium alloy prepared in this embodiment is 1355.15 MPa, the yield strength is 1253.05 MPa, and the elongation after fracture is 5.52%.

[0059] The above are only the preferred embodiments of the present invention and do not impose any limitations on the present invention. Any simple modifications, changes, and equivalent changes made to the above embodiments according to the technical essence of the invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A method for improving the strength of additively manufactured titanium alloys, characterized in that, The method comprises the following steps: Step 1: Add tungsten powder to the spherical Ti185 alloy powder prepared by plasma rotating electrode atomization, and then mix them using a planetary ball mill to obtain a mixed powder; the spherical Ti185 alloy powder is composed of the following components by mass content: Al 1.38%, V 8.00%, Fe 4.22%, O 0.19%, and the balance is titanium and unavoidable impurities. The particle size of the spherical Ti185 alloy powder is 40 μm to 150 μm, the particle size of the tungsten powder is 1 μm to 10 μm, and the mass of the tungsten powder in the mixed powder is 5% to 15% of the mass of the Ti185 alloy powder; Step 2: Draw a three-dimensional model of the target product, and then cut it into equal-thickness slices along its height direction for layer-by-layer processing to obtain sliced data. Then, design the internal scanning method and scanning path for each slice to obtain sliced scanning data; the thickness of the slice is 0.05 mm to 0.1 mm; Step 3: Import the sliced data and sliced scanning data obtained in Step 2 into a powder bed electron beam additive manufacturing forming device. Load the mixed powder obtained in Step 1 into the powder box of the powder bed electron beam additive manufacturing forming device, and then level the forming bottom plate of the powder bed electron beam additive manufacturing forming device and preheat the forming bottom plate; the preheating temperature of the forming bottom plate is 700 °C to 720 °C; Step 4: Lay the mixed powder loaded into the powder box in Step 3 on the preheated forming bottom plate to form a powder layer, and then preheat the powder layer; the preheating temperature of the powder layer is 700 °C to 720 °C, and the thickness of the laid mixed powder is the same as the thickness of each slice in Step 2; Step 5: According to the sliced data and sliced scanning data imported into the powder bed electron beam additive manufacturing forming device in Step 2, use an electron beam to melt and scan the preheated powder layer in Step 4 to form a single-layer solid slice, and then lower the forming bottom plate; the height by which the forming bottom plate is lowered is the same as the thickness of each slice in Step 2; the process parameters of the melting scan are: the scanning line spacing is 0.05 mm to 0.1 mm, the scanning current is 6 mA to 15 mA, and the scanning speed is 1400 mm / s to 3000 mm / s; Step 6: Repeat Step 4 and Step 5 until each single-layer solid slice is stacked layer by layer to form a powder bed electron beam additive manufacturing formed part. Then, take it out when the temperature of the forming bottom plate is less than 100 °C, and use high-pressure gas to remove the residual powder on the surface of the powder bed electron beam additive manufacturing formed part to obtain a reinforced titanium alloy; the tensile strength of the reinforced titanium alloy is higher than 1355 MPa, the tensile yield strength is higher than 1253 MPa, and the elongation after fracture is higher than 5%.

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