Ti-6al-4v-0.25si titanium alloy powder for additive manufacturing and method of making same, titanium alloy part

Abstract

This disclosure provides Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing, its preparation method, and titanium alloy parts; the Ti-6Al-4V-0.25Si titanium alloy powder comprises, by mass percentage: Al: greater than or equal to 5.5 wt.% and less than or equal to 6.75 wt.%; V: greater than or equal to 3.5 wt.% and less than or equal to 4.5 wt.%; Si: greater than or equal to 0.1 wt.% and less than or equal to 0.5 wt.%; Fe: less than or equal to 0.30 wt.%; O: less than or equal to 0.20 wt.%; C: less than or equal to 0.08 wt.%; H: less than or equal to 0.015 wt.%; N: less than or equal to 0.05 wt.%; the balance being Ti.

Description

Technical Field

[0001] This disclosure relates to the field of additive manufacturing technology, and in particular to Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing, its preparation method, and titanium alloy parts. Background Technology

[0002] Titanium (Ti) and titanium alloys, due to their low density, high specific strength, good biocompatibility, and excellent oxidation and corrosion resistance, have very important applications in aerospace and medical fields. TC4 titanium alloy (Ti-6Al-4V), as a widely used titanium alloy, is extensively used in the aerospace industry to manufacture engine fans, compressor disks and blades, as well as critical load-bearing components such as beams, joints, and bulkheads in aircraft structures. In the medical field, TC4 titanium alloy is also used to manufacture implantable devices. With the increasingly widespread application of TC4 titanium alloy, the requirements for its strength are also constantly increasing.

[0003] Additive manufacturing, also known as 3D printing, is a technology that manufactures solid parts by depositing materials layer by layer based on three-dimensional model data. This technology can produce parts with complex shapes and structures and offers advantages such as mass production, short production cycles, and high precision in the formed products.

[0004] Based on the above description, developing a titanium alloy powder for additive manufacturing technology to produce high-strength titanium alloy parts has become an urgent problem to be solved. Summary of the Invention

[0005] This disclosure provides Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing, a method for preparing the same, and titanium alloy parts; it enables the provision of Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing to produce high-strength Ti-6Al-4V-0.25Si titanium alloy parts.

[0006] The technical solution disclosed herein is implemented as follows: In a first aspect, this disclosure provides a Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing, wherein the Ti-6Al-4V-0.25Si titanium alloy powder comprises, by mass percentage: Al: ≥5.5 wt.% and ≤6.75 ​​wt.%; V: Greater than or equal to 3.5 wt.% and less than or equal to 4.5 wt.%; Si: greater than or equal to 0.1 wt.% and less than or equal to 0.5 wt.%; Fe: less than or equal to 0.30 wt.%; O: less than or equal to 0.20 wt.%; C: less than or equal to 0.08 wt.%; H: less than or equal to 0.015 wt.%; N: less than or equal to 0.05 wt.%; The margin is Ti.

[0007] In some possible implementations, Si is greater than or equal to 0.1 wt.% and less than or equal to 0.25 wt.% by mass percentage.

[0008] In some possible implementations, Si is greater than 0.25 wt.% and less than or equal to 0.40 wt.% by mass percentage.

[0009] In some possible implementations, Si, by mass percentage, is greater than 0.4 wt.% and less than or equal to 0.50 wt.%.

[0010] In some possible implementations, the particle size of the Ti-6Al-4V-0.25Si titanium alloy powder is greater than or equal to 15 μm or less than or equal to 53 μm, or the particle size of the Ti-6Al-4V-0.25Si titanium alloy powder is greater than or equal to 53 μm and less than or equal to 180 μm.

[0011] In a second aspect, this disclosure provides a method for preparing Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing, the method being used to prepare the Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing according to the first aspect, the method comprising: The raw material powder of a set ratio is loaded into a set titanium alloy sleeve and then prepared into Ti-6Al-4V-0.25Si titanium alloy rod by hot isostatic pressing. After induction melting of the Ti-6Al-4V-0.25Si titanium alloy rod, Ti-6Al-4V-0.25Si titanium alloy powder was prepared by gas atomization.

[0012] In some possible implementations, the hot isostatic pressing method corresponds to a temperature greater than or equal to 900°C and less than or equal to 950°C, a pressure greater than or equal to 120MPa and less than or equal to 150MPa, a holding time greater than or equal to 2h and less than or equal to 4h, and cooling with the furnace.

[0013] In some possible embodiments, the preparation method further includes: performing particle size sieving on the Ti-6Al-4V-0.25Si titanium alloy powder prepared by gas atomization.

[0014] Thirdly, this disclosure provides a Ti-6Al-4V-0.25Si titanium alloy part, which is obtained by additive manufacturing based on the Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing as described in the first aspect.

[0015] In some possible implementations, the Ti-6Al-4V-0.25Si titanium alloy part has a tensile strength of not less than 1250 MPa at room temperature, a yield strength of not less than 1100 MPa at room temperature, and an elongation of not less than 8%; and the Ti-6Al-4V-0.25Si titanium alloy part has a tensile strength of not less than 1000 MPa, a yield strength of not less than 850 MPa, and an elongation of not less than 9% at a temperature of 400°C.

[0016] In some possible implementations, the Ti-6Al-4V-0.25Si titanium alloy part has a tensile strength at room temperature greater than or equal to 1250 MPa and less than or equal to 1450 MPa, a room temperature yield strength greater than or equal to 1100 MPa and less than or equal to 1300 MPa, and an elongation greater than or equal to 8% and less than or equal to 14%; and the Ti-6Al-4V-0.25Si titanium alloy part has a tensile strength at 400°C greater than or equal to 1000 MPa and less than or equal to 1120 MPa, a yield strength greater than or equal to 850 MPa and less than or equal to 950 MPa, and an elongation greater than or equal to 9% and less than or equal to 13%.

[0017] This disclosure provides Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing, its preparation method, and titanium alloy parts; by adding an appropriate amount of silicon (Si) component to TC4 titanium alloy powder, the strength of the Ti-6Al-4V-0.25Si titanium alloy parts obtained by additive manufacturing is improved through the solid solution strengthening and precipitation strengthening effects of the Si component. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of a method for preparing Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing, as provided in this disclosure.

[0019] Figure 2 Metallographic diagram of the Ti-6Al-4V-0.25Si titanium alloy part provided in Embodiment 1 of this disclosure in the forming direction XY.

[0020] Figure 3 The metallographic structure of the Ti-6Al-4V-0.25Si titanium alloy part provided in Embodiment 1 of this disclosure is shown in the Z-direction of the forming direction.

[0021] Figure 4The image shows the metallographic structure of the Ti-6Al-4V-0.25Si titanium alloy bar provided in Embodiment 3 of this disclosure.

[0022] Figure 5 The image shows the microstructure of the Ti-6Al-4V-0.25Si titanium alloy powder provided in Example 3 of this disclosure.

[0023] Figure 6 Metallographic diagram of the Ti-6Al-4V-0.25Si titanium alloy part provided in Embodiment 3 of this disclosure in the forming direction XY.

[0024] Figure 7 The metallographic structure of the Ti-6Al-4V-0.25Si titanium alloy part provided in Embodiment 3 of this disclosure is shown in the Z-direction of the forming direction.

[0025] Figure 8 Metallographic diagram of the Ti-6Al-4V-0.25Si titanium alloy part provided in Embodiment 5 of this disclosure in the forming direction XY.

[0026] Figure 9 The metallographic structure of the Ti-6Al-4V-0.25Si titanium alloy part provided in Embodiment 5 of this disclosure is shown in the Z-direction of the forming direction. Detailed Implementation

[0027] The technical solutions in this disclosure will now be clearly and completely described with reference to the accompanying drawings.

[0028] This disclosure provides a Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing, wherein the Ti-6Al-4V-0.25Si titanium alloy powder comprises, by weight percentage: Al: ≥5.5 wt.% and ≤6.75 ​​wt.%; V: Greater than or equal to 3.5 wt.% and less than or equal to 4.5 wt.%; Si: greater than or equal to 0.1 wt.% and less than or equal to 0.5 wt.%; Fe: less than or equal to 0.30 wt.%; O: less than or equal to 0.20 wt.%; C: less than or equal to 0.08 wt.%; H: less than or equal to 0.015 wt.%; N: less than or equal to 0.05 wt.%; The margin is Ti.

[0029] The Ti-6Al-4V-0.25Si titanium alloy powder provided in this embodiment is obtained by adding an appropriate amount of Si component to TC4 titanium alloy powder. Understandably, TC4 titanium alloy, as a typical (α+β) type titanium alloy, exhibits significantly improved performance through the addition of Si component. This is mainly because Si component is an active eutectoid β-stabilizing element, with a relatively fast eutectoid reaction rate. Under normal cooling conditions, the β phase can be completely decomposed, thereby enabling TC4 titanium alloy to possess age-hardening capabilities. Specifically, after introducing Si component into TC4 titanium alloy powder, the Si component can dissolve in the titanium matrix. With the increase of Si component content, Ti5Si3 silicide gradually precipitates. This Ti5Si3 silicide, as an intermetallic compound with extremely high heat resistance, is not only a good strengthening phase but also possesses low density, high melting point, high Young's modulus, and good high-temperature oxidation resistance. Therefore, by adjusting the composition and ratio of TC4 titanium alloy powder, not only can the strength of the manufactured titanium alloy parts be improved through solid solution strengthening and precipitation strengthening, but its heat resistance and high-temperature stability can also be significantly enhanced.

[0030] In this embodiment, the Si content is limited to the range of 0.1 wt.% to 0.5 wt.%. On the one hand, if the Si content is too low, for example below 0.1 wt%, the precipitation of Ti5Si3 silicides will be insufficient, resulting in insignificant solid solution strengthening and precipitation strengthening effects, and failing to effectively improve the strength of the manufactured titanium alloy parts. On the other hand, if the Si content is too high, for example above 0.5 wt.%, the excessive precipitated Ti5Si3 silicides are prone to segregation at grain boundaries, which negatively impacts the plasticity of the manufactured titanium alloy parts and increases their fracture risk. Therefore, by controlling the Si content within the range of 0.1 wt.% to 0.5 wt.%, it is possible to ensure that the manufactured Ti-6Al-4V-0.25Si titanium alloy parts possess both the required strength and good plasticity.

[0031] In some examples, Si is greater than or equal to 0.1 wt.% and less than or equal to 0.25 wt.% by mass percentage.

[0032] When the Si content is between 0.1 wt.% and 0.25 wt.%, the manufacturing process of Ti-6Al-4V-0.25Si titanium alloy ensures that the Si component is fully dissolved in the titanium matrix, and that an appropriate amount of Ti5Si3 silicide precipitates, effectively improving the strength of the titanium alloy parts. Furthermore, by limiting the Si content to a lower level, the segregation of Ti5Si3 silicide at grain boundaries can be reduced, thereby maintaining the ductile properties of the titanium alloy parts.

[0033] In some examples, Si is greater than 0.25 wt.% and less than or equal to 0.40 wt.% by mass percentage.

[0034] When the Si content is controlled within the range of 0.25 wt.% to 0.40 wt.%, it helps to promote the effective precipitation of Ti5Si3 silicides, enhances the precipitation strengthening effect, and thus significantly improves the strength of Ti-6Al-4V-0.25Si titanium alloy parts. Meanwhile, within this content range, since the segregation of Ti5Si3 silicides at the grain boundaries is not significant, it has little impact on the plasticity of Ti-6Al-4V-0.25Si titanium alloy parts, allowing for higher strength while maintaining plasticity.

[0035] In some examples, Si is greater than 0.4 wt.% and less than or equal to 0.50 wt.% by mass percentage.

[0036] When the Si content is set between 0.4 wt.% and 0.50 wt.%, it further promotes the precipitation of Ti5Si3 silicides, enhancing the precipitation strengthening effect and thus significantly improving the strength of the titanium alloy. However, within this content range, there is also a risk of Ti5Si3 silicides segregating at the grain boundaries, which may have a certain impact on the plasticity of the titanium alloy parts. Nevertheless, by precisely controlling the Si content, a significant improvement in the strength of Ti-6Al-4V-0.25Si titanium alloy parts can be achieved while ensuring that the plasticity of the titanium alloy parts is not excessively reduced.

[0037] In some possible implementations of the above technical solutions, the particle size of Ti-6Al-4V-0.25Si titanium alloy powder is greater than or equal to 15μm and less than or equal to 53μm, or the particle size of Ti-6Al-4V-0.25Si titanium alloy powder is greater than or equal to 53μm and less than or equal to 180μm.

[0038] In additive manufacturing, the particle size of Ti-6Al-4V-0.25Si titanium alloy powder has a significant impact on powder flowability. Generally speaking, smaller particle size Ti-6Al-4V-0.25Si titanium alloy powder can improve powder flowability, but excessively fine titanium alloy powder may adhere to each other due to electrostatic effects, reducing flowability.

[0039] For additive manufacturing technologies employing powder spreading processes, smaller particle sizes of Ti-6Al-4V-0.25Si titanium alloy powder (e.g., 15 μm to 53 μm) facilitate uniform spreading. Furthermore, the smaller particle size of Ti-6Al-4V-0.25Si titanium alloy powder provides a larger surface area, thereby improving laser energy absorption efficiency and contributing to enhanced melting and solidification uniformity. In addition, additive manufacturing technologies employing powder feeding processes allow for a wider range of Ti-6Al-4V-0.25Si titanium alloy powder particle sizes, such as 53 μm to 180 μm.

[0040] In addition, such as Figure 1 As shown, this disclosure also provides a method for preparing Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing. This preparation method is used to prepare Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing according to the foregoing technical solution. The preparation method specifically includes the following steps.

[0041] In step S101, a set proportion of raw material powder is loaded into a set titanium alloy sleeve, and Ti-6Al-4V-0.25Si titanium alloy rods are prepared by hot isostatic pressing.

[0042] In some examples, the aforementioned raw material powder can be obtained by adding one or more of silicon dioxide powder, silicon carbide powder, titanium silicide powder, or aluminum-silicon alloy powder to titanium powder, vanadium powder, aluminum-vanadium alloy powder, or TC4 powder. It should be noted that one or more of the aforementioned silicon dioxide powder, silicon carbide powder, titanium silicide powder, or aluminum-silicon alloy powder are used to introduce the Si component.

[0043] In some examples, the titanium alloy material can be TC4, but in practice it is not limited to TC4 and can be determined according to the actual situation.

[0044] In the specific implementation process, the raw material powders of a predetermined proportion are uniformly mixed in a mixer and then loaded into a titanium alloy sheath. The Ti-6Al-4V-0.25Si titanium alloy rods are then prepared by hot isostatic pressing. It is understood that, in this disclosure, loading the raw material powders into a sheath, such as TC4 material, avoids the risk of introducing impurities as seen in related technologies using steel pipes or similar materials as sheaths. Furthermore, the method of mixing the raw material powders in this disclosure results in a more uniform distribution of the components in the formed Ti-6Al-4V-0.25Si titanium alloy rods.

[0045] The specific dimensions of the Ti-6Al-4V-0.25Si titanium alloy rods disclosed herein are not specifically limited and can be determined according to actual needs.

[0046] In step S102, Ti-6Al-4V-0.25Si titanium alloy rods are induction melted and then Ti-6Al-4V-0.25Si titanium alloy powder is prepared by gas atomization.

[0047] In practice, the Ti-6Al-4V-0.25Si titanium alloy rod obtained in step S102 can be loaded into, for example, an Electrode Induction Melting Gas Atomization (EIGA) device, and heated using a conical induction coil in the EIGA device. Understandably, the melted Ti-6Al-4V-0.25Si titanium alloy droplets can be forcibly broken up and cooled after passing through a high-pressure argon nozzle at the lower end of the EIGA device, thereby forming spherical powder with a certain particle size range.

[0048] It should be noted that in some examples, the temperature corresponding to the above hot isostatic pressing method is greater than or equal to 900℃ and less than or equal to 950℃, the pressure is greater than or equal to 120MPa and less than or equal to 150MPa, the heat and pressure holding time is greater than or equal to 2h and less than or equal to 4h, and the furnace is cooled together.

[0049] In some possible embodiments, the preparation method further includes: performing particle size sieving on the Ti-6Al-4V-0.25Si titanium alloy powder prepared by gas atomization.

[0050] Understandably, after obtaining Ti-6Al-4V-0.25Si titanium alloy spherical powder through step S102, it is usually necessary to pass these Ti-6Al-4V-0.25Si titanium alloy spherical powders obtained in step S102 through a particle size sieving device to obtain Ti-6Al-4V-0.25Si titanium alloy powders of the required particle size for additive manufacturing.

[0051] It should be noted that in this disclosure, Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing is prepared using the EIGA method, and then Ti-6Al-4V-0.25Si titanium alloy parts are manufactured using additive manufacturing technologies, such as Selective Laser Melting (SLM). The entire manufacturing process involves the remelting of the aforementioned raw material powder and the remelting of the Ti-6Al-4V-0.25Si titanium alloy powder, as well as high-temperature and rapid solidification processes. This results in Ti-6Al-4V-0.25Si titanium alloy parts with more uniform chemical composition, finer microstructure, and good matching of strength and plasticity properties.

[0052] Based on this, the present disclosure also provides a Ti-6Al-4V-0.25Si titanium alloy part, which is obtained by additive manufacturing of Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing as described in the foregoing technical solution.

[0053] In some possible implementations, the Ti-6Al-4V-0.25Si titanium alloy part has a tensile strength of not less than 1250 MPa at room temperature, a yield strength of not less than 1100 MPa at room temperature, and an elongation of not less than 8%; and the Ti-6Al-4V-0.25Si titanium alloy part has a tensile strength of not less than 1000 MPa, a yield strength of not less than 850 MPa, and an elongation of not less than 9% at a temperature of 400°C.

[0054] In some possible implementations, the Ti-6Al-4V-0.25Si titanium alloy part has a tensile strength at room temperature greater than or equal to 1250 MPa and less than or equal to 1450 MPa, a room temperature yield strength greater than or equal to 1100 MPa and less than or equal to 1300 MPa, and an elongation greater than or equal to 8% and less than or equal to 14%; and the Ti-6Al-4V-0.25Si titanium alloy part has a tensile strength at 400°C greater than or equal to 1000 MPa and less than or equal to 1120 MPa, a yield strength greater than or equal to 850 MPa and less than or equal to 950 MPa, and an elongation greater than or equal to 9% and less than or equal to 13%.

[0055] The technical solution of this disclosure will be described in detail below through specific embodiments.

[0056] Example 1: A Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing, comprising, by mass percentage: Al: 5.5 wt.%; V: 3.5 wt.%; Si: 0.1 wt.%; Fe: 0.30 wt.%; O: 0.20 wt.%; C: 0.08 wt.%; H: 0.015 wt.%; N: 0.05 wt.%; with the balance being Ti.

[0057] In some examples, the preparation method of Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing provided in Example 1 is as follows: Step S1: The raw material powder of a set ratio is loaded into a TC4 material sleeve and Ti-6Al-4V-0.25Si titanium alloy rod is prepared by hot isostatic pressing; wherein, the corresponding temperature of hot isostatic pressing is 920℃, the pressure is 150MPa, the holding time is 3h and the furnace is cooled.

[0058] Step S2: After induction melting of Ti-6Al-4V-0.25Si titanium alloy rods, Ti-6Al-4V-0.25Si titanium alloy powder is prepared by EIGA method.

[0059] Step S3: Perform particle size sieving on the Ti-6Al-4V-0.25Si titanium alloy powder obtained in step S2 to obtain Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing; wherein the particle size of the Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing is in the range of 15μm to 53μm.

[0060] Based on the Ti-6Al-4V-0.25Si titanium alloy powder obtained in step S3 for additive manufacturing, Ti-6Al-4V-0.25Si titanium alloy parts were manufactured using selective laser melting (SLM). See also... Figure 2 and Figure 3 The figures show the metallographic structures of the Ti-6Al-4V-0.25Si titanium alloy parts in the forming directions XY and Z, respectively. Tables 1 and 2 show the mechanical properties of the manufactured Ti-6Al-4V-0.25Si titanium alloy parts at room temperature and 400℃, respectively.

[0061] It should be noted that in the above forming directions XY, X refers to the length direction of the substrate in the forming chamber of the selective laser melting equipment, and Y refers to the width direction of the substrate. The above forming direction Z refers to the thickness direction of the substrate.

[0062]

[0063] Table 1

[0064] Table 2 Example 2: A Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing, comprising, by mass percentage: Al: 6.75 wt.%; V: 4.5 wt.%; Si: 0.25 wt.%; Fe: 0.15 wt.%; O: 0.10 wt.%; C: 0.07 wt.%; H: 0.010 wt.%; N: 0.01 wt.%; with the balance being Ti.

[0065] In some examples, the preparation method of Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing provided in Example 2 is as follows: Step S1: The raw material powder of a set ratio is loaded into a TC4 material sleeve and Ti-6Al-4V-0.25Si titanium alloy rod is prepared by hot isostatic pressing; wherein, the corresponding temperature of hot isostatic pressing is 920℃, the pressure is 150MPa, the holding time is 3h and the furnace is cooled.

[0066] Step S2: After induction melting of Ti-6Al-4V-0.25Si titanium alloy rods, Ti-6Al-4V-0.25Si titanium alloy powder is prepared by EIGA method.

[0067] Step S3: Perform particle size sieving on the Ti-6Al-4V-0.25Si titanium alloy powder obtained in step S2 to obtain Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing; wherein the particle size of the Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing is in the range of 15μm to 53μm.

[0068] Based on the Ti-6Al-4V-0.25Si titanium alloy powder obtained in step S3 for additive manufacturing, Ti-6Al-4V-0.25Si titanium alloy parts were manufactured using selective laser melting (SLM). See Tables 3 and 4, which show the mechanical properties of the manufactured Ti-6Al-4V-0.25Si titanium alloy parts at room temperature and 400°C, respectively.

[0069]

[0070] Table 3

[0071] Table 4 Example 3: A Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing, comprising, by mass percentage: Al: 6.0 wt.%; V: 3.7 wt.%; Si: 0.27 wt.%; Fe: 0.20 wt.%; O: 0.17 wt.%; C: 0.065 wt.%; H: 0.015 wt.%; N: 0.03 wt.%; with the balance being Ti.

[0072] In some examples, the preparation method of Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing provided in Example 3 is as follows: Step S1: The raw material powder of a set ratio is loaded into a TC4 material sleeve and Ti-6Al-4V-0.25Si titanium alloy rod is prepared by hot isostatic pressing; wherein, the corresponding temperature of hot isostatic pressing is 900℃, the pressure is 120MPa, the holding time is 3h and the furnace is cooled.

[0073] It should be noted that the metallographic structure of the Ti-6Al-4V-0.25Si titanium alloy bar is as follows: Figure 4 As shown.

[0074] Step S2: After induction melting of Ti-6Al-4V-0.25Si titanium alloy rods, Ti-6Al-4V-0.25Si titanium alloy powder was prepared by EIGA method. The microstructure of the Ti-6Al-4V-0.25Si titanium alloy powder is shown in the figure below. Figure 5 As shown.

[0075] Step S3: Perform particle size sieving on the Ti-6Al-4V-0.25Si titanium alloy powder obtained in step S2 to obtain Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing; wherein the particle size of the Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing is in the range of 15μm to 53μm.

[0076] Based on the Ti-6Al-4V-0.25Si titanium alloy powder obtained in step S3 for additive manufacturing, Ti-6Al-4V-0.25Si titanium alloy parts were manufactured using selective laser melting (SLM). See also... Figure 6 and Figure 7 The figures show the metallographic structures of the Ti-6Al-4V-0.25Si titanium alloy parts in the forming directions XY and Z, respectively. Tables 5 and 6 show the mechanical properties of the manufactured Ti-6Al-4V-0.25Si titanium alloy parts at room temperature and 400℃, respectively.

[0077]

[0078] Table 5

[0079] Table 6 Example 4: A Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing, comprising, by mass percentage: Al: 6.0 wt.%; V: 4.2 wt.%; Si: 0.40 wt.%; Fe: 0.25 wt.%; O: 0.15 wt.%; C: 0.05 wt.%; H: 0.005 wt.%; N: 0.02 wt.%; with the balance being Ti.

[0080] In some examples, the preparation method of Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing provided in Example 4 is as follows: Step S1: The raw material powder of a set ratio is loaded into a TC4 material sleeve and Ti-6Al-4V-0.25Si titanium alloy rod is prepared by hot isostatic pressing; wherein, the corresponding temperature of hot isostatic pressing is 900℃, the pressure is 120MPa, the holding time is 4h and the furnace is cooled.

[0081] Step S2: Induction melting was performed on Ti-6Al-4V-0.25Si titanium alloy rods, and Ti-6Al-4V-0.25Si titanium alloy powder was prepared by EIGA method.

[0082] Step S3: Perform particle size sieving on the Ti-6Al-4V-0.25Si titanium alloy powder obtained in step S2 to obtain Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing; wherein the particle size of the Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing is in the range of 15μm to 53μm.

[0083] Based on the Ti-6Al-4V-0.25Si titanium alloy powder obtained in step S3 for additive manufacturing, Ti-6Al-4V-0.25Si titanium alloy parts were manufactured using selective laser melting (SLM). See Tables 7 and 8, which show the mechanical properties of the manufactured Ti-6Al-4V-0.25Si titanium alloy parts at room temperature and 400°C, respectively.

[0084]

[0085] Table 7

[0086] Table 8 Example 5: A Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing, comprising, by mass percentage: Al: 6.25wt.%; V: 4.0wt.%; Si: 0.41wt.%; Fe: 0.30wt.%; O: 0.15wt.%; C: 0.005wt.%; H: 0.015wt.%; N: 0.045wt.%; with the balance being Ti.

[0087] In some examples, the preparation method of Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing provided in Example 5 is as follows: Step S1: The raw material powder of a set ratio is loaded into a TC4 material sleeve and Ti-6Al-4V-0.25Si titanium alloy rod is prepared by hot isostatic pressing; wherein, the corresponding temperature of hot isostatic pressing is 950℃, the pressure is 150MPa, the holding time is 3h and the furnace is cooled.

[0088] Step S2: After induction melting of Ti-6Al-4V-0.25Si titanium alloy rods, Ti-6Al-4V-0.25Si titanium alloy powder is prepared by EIGA method.

[0089] Step S3: Perform particle size sieving on the Ti-6Al-4V-0.25Si titanium alloy powder obtained in step S2 to obtain Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing; wherein the particle size of the Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing is in the range of 15μm to 53μm.

[0090] Based on the Ti-6Al-4V-0.25Si titanium alloy powder obtained in step S3 for additive manufacturing, Ti-6Al-4V-0.25Si titanium alloy parts were manufactured using selective laser melting (SLM). See also... Figure 8 and Figure 9 The figures show the metallographic structures of the Ti-6Al-4V-0.25Si titanium alloy parts in the forming directions XY and Z, respectively. Tables 9 and 10 show the mechanical properties of the manufactured Ti-6Al-4V-0.25Si titanium alloy parts at room temperature and 400°C, respectively.

[0091]

[0092] Table 9

[0093] Table 10 Example 6: A Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing, comprising, by mass percentage: Al: 6.1 wt.%; V: 4.4 wt.%; Si: 0.50 wt.%; Fe: 0.20 wt.%; O: 0.10 wt.%; C: 0.06 wt.%; H: 0.008 wt.%; N: 0.04 wt.%; with the balance being Ti.

[0094] In some examples, the preparation method of Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing provided in Example 6 is as follows: Step S1: The raw material powder of a set ratio is loaded into a TC4 material sleeve and Ti-6Al-4V-0.25Si titanium alloy rod is prepared by hot isostatic pressing; wherein, the corresponding temperature of hot isostatic pressing is 950℃, the pressure is 150MPa, the holding time is 2h and the furnace is cooled.

[0095] Step S2: After induction melting of Ti-6Al-4V-0.25Si titanium alloy rods, Ti-6Al-4V-0.25Si titanium alloy powder is prepared by EIGA method.

[0096] Step S3: Perform particle size sieving on the Ti-6Al-4V-0.25Si titanium alloy powder obtained in step S2 to obtain Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing; wherein the particle size of the Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing is in the range of 15μm to 53μm.

[0097] Based on the Ti-6Al-4V-0.25Si titanium alloy powder obtained in step S3 for additive manufacturing, Ti-6Al-4V-0.25Si titanium alloy parts were manufactured using selective laser melting (SLM). See Tables 11 and 12, which show the mechanical properties of the manufactured Ti-6Al-4V-0.25Si titanium alloy parts at room temperature and 400°C, respectively.

[0098]

[0099] Table 11

[0100] Table 12 Example 7: A Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing, comprising, by mass percentage: Al: 5.75 wt.%; V: 3.92 wt.%; Si: 0.15 wt.%; Fe: 0.25 wt.%; O: 0.15 wt.%; C: 0.072 wt.%; H: 0.015 wt.%; N: 0.04 wt.%; with the balance being Ti.

[0101] In some examples, the preparation method of Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing provided in Example 7 is as follows: Step S1: The raw material powder of a set ratio is loaded into a TC4 material sleeve and Ti-6Al-4V-0.25Si titanium alloy rod is prepared by hot isostatic pressing; wherein, the corresponding temperature of hot isostatic pressing is 920℃, the pressure is 150MPa, the holding time is 2.5h and the furnace is cooled.

[0102] Step S2: After induction melting of Ti-6Al-4V-0.25Si titanium alloy rods, Ti-6Al-4V-0.25Si titanium alloy powder is prepared by EIGA method.

[0103] Step S3: Perform particle size sieving on the Ti-6Al-4V-0.25Si titanium alloy powder obtained in step S2 to obtain Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing; wherein the particle size of the Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing is in the range of 15μm to 53μm.

[0104] Based on the Ti-6Al-4V-0.25Si titanium alloy powder obtained in step S3 for additive manufacturing, Ti-6Al-4V-0.25Si titanium alloy parts were manufactured using selective laser melting (SLM). See Tables 13 and 14, which show the mechanical properties of the manufactured Ti-6Al-4V-0.25Si titanium alloy parts at room temperature and 400°C, respectively.

[0105]

[0106] Table 13

[0107] Table 14 Comparative Example 1: A TC4 titanium alloy powder for additive manufacturing, comprising, by weight percentage: Al: 6.22 wt.%; V: 3.95 wt.%; Fe: 0.13 wt.%; O: 0.094 wt.%; C: 0.015 wt.%; H: 0.0044 wt.%; N: 0.012 wt.%; with the balance being Ti.

[0108] In some examples, the method for preparing TC4 titanium alloy powder for additive manufacturing provided in Comparative Example 1 is as follows: Step S1: The raw material powder of a set ratio is loaded into a TC4 material sleeve and prepared into TC4 titanium alloy rods by hot isostatic pressing; wherein, the corresponding temperature of hot isostatic pressing is 920℃, the pressure is 150MPa, the holding time is 3h and the furnace is cooled.

[0109] Step S2: Induction melting is performed on TC4 titanium alloy bars to prepare TC4 titanium alloy powder by EIGA method.

[0110] Step S3: Perform particle size sieving on the TC4 titanium alloy powder prepared in step S2 to obtain TC4 titanium alloy powder for additive manufacturing; wherein the particle size of the TC4 titanium alloy powder for additive manufacturing is in the range of 15μm to 53μm.

[0111] Based on the TC4 titanium alloy powder obtained in step S3 for additive manufacturing, TC4 titanium alloy parts were manufactured using selective laser melting (SLM). See Tables 15 and 16, which show the mechanical properties of the manufactured TC4 titanium alloy parts at room temperature and 400°C, respectively.

[0112]

[0113] Table 15

[0114] Table 16 By comparing Examples 1 to 7 and Comparative Example 1, it can be found that when Si component is added and the content of Si component is in the range of 0.1 wt.% to 0.5 wt.%, the strength of Ti-6Al-4V-0.25Si titanium alloy parts manufactured by selective laser melting technology is significantly improved at room temperature and 400°C.

[0115] Comparative Example 2: A titanium alloy powder for additive manufacturing, comprising, by weight percentage: Al: 6.22 wt.%; V: 3.85 wt.%; Si: 0.58 wt.%; Fe: 0.11 wt.%; O: 0.13 wt.%; C: 0.016 wt.%; H: 0.0028 wt.%; N: 0.095 wt.%; with the balance being Ti.

[0116] In some examples, the method for preparing titanium alloy powder for additive manufacturing provided in Comparative Example 2 is as follows: Step S1: The raw material powder of a set ratio is loaded into a TC4 material sleeve and prepared into titanium alloy rods by hot isostatic pressing; wherein, the corresponding temperature of hot isostatic pressing is 920℃, the pressure is 150MPa, the holding time is 3h and the furnace is cooled.

[0117] Step S2: The titanium alloy rod is induction melted to obtain titanium alloy powder by EIGA method.

[0118] Step S3: Perform particle size sieving on the titanium alloy powder prepared in step S2 to obtain titanium alloy powder for additive manufacturing; wherein the particle size of the titanium alloy powder for additive manufacturing is in the range of 15μm to 53μm.

[0119] Based on the titanium alloy powder obtained in step S3 for additive manufacturing, titanium alloy parts were manufactured using selective laser melting (SLM). See Table 17, which shows the mechanical properties of the manufactured titanium alloy parts at room temperature.

[0120]

[0121] Table 17 In Comparative Example 2, although the titanium alloy part exhibits high strength at room temperature when the Si content is 0.58 wt.%, it fractures at 400°C. This is because at 400°C, the precipitated Ti5Si3 silicides hinder dislocation movement in the titanium matrix, reducing the synergistic effect of plastic deformation between adjacent grains. As the Ti5Si3 silicides at the grain boundaries gradually grow, they connect together, disrupting grain boundary continuity and increasing mismatch between the titanium matrix particles. Therefore, during deformation, the Ti5Si3 silicides and the titanium matrix cannot effectively coordinate deformation, leading to stress concentration and ultimately crack initiation. This makes the titanium alloy part prone to fracture even under relatively small stresses.

[0122] It should be noted that the technical solutions described in this disclosure can be combined arbitrarily as long as they do not conflict.

[0123] The above description is merely a specific embodiment of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. A Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing, characterized in that, The Ti-6Al-4V-0.25Si titanium alloy powder comprises, by weight percentage: Al: ≥5.5 wt.% and ≤6.75 ​​wt.%; V: Greater than or equal to 3.5 wt.% and less than or equal to 4.5 wt.%; Si: greater than or equal to 0.1 wt.% and less than or equal to 0.5 wt.%; Fe: less than or equal to 0.30 wt.%; O: less than or equal to 0.20 wt.%; C: less than or equal to 0.08 wt.%; H: less than or equal to 0.015 wt.%; N: less than or equal to 0.05 wt.%; The margin is Ti.

2. The Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing according to claim 1, characterized in that, By mass percentage, Si: greater than or equal to 0.1 wt.% and less than or equal to 0.25 wt.%.

3. The Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing according to claim 1, characterized in that, By mass percentage, Si: greater than 0.25 wt.% and less than or equal to 0.40 wt.%.

4. The Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing according to claim 1, characterized in that, By mass percentage, Si: greater than 0.4 wt.% and less than or equal to 0.50 wt.%.

5. The Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing according to any one of claims 1 to 4, characterized in that, The particle size of the Ti-6Al-4V-0.25Si titanium alloy powder is greater than or equal to 15μm and less than or equal to 53μm, or the particle size of the Ti-6Al-4V-0.25Si titanium alloy powder is greater than or equal to 53μm and less than or equal to 180μm.

6. A method for preparing Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing, characterized in that, The preparation method is used to prepare Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing according to any one of claims 1 to 5, the preparation method comprising: The raw material powder of a set ratio is loaded into a set titanium alloy sleeve and then prepared into Ti-6Al-4V-0.25Si titanium alloy rod by hot isostatic pressing. After induction melting of the Ti-6Al-4V-0.25Si titanium alloy rod, the Ti-6Al-4V-0.25Si titanium alloy powder was prepared by gas atomization.

7. The method for preparing Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing according to claim 6, characterized in that, The hot isostatic pressing method is used when the temperature is greater than or equal to 900℃ and less than or equal to 950℃, the pressure is greater than or equal to 120MPa and less than or equal to 150MPa, the heat and pressure holding time is greater than or equal to 2h and less than or equal to 4h, and the furnace is cooled.

8. The method for preparing Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing according to claim 6, characterized in that, The preparation method further includes: performing particle size sieving on the Ti-6Al-4V-0.25Si titanium alloy powder prepared by gas atomization.

9. A Ti-6Al-4V-0.25Si titanium alloy part, characterized in that, The Ti-6Al-4V-0.25Si titanium alloy parts described in any one of claims 1 to 5 are obtained by additive manufacturing of Ti-6Al-4V-0.25Si titanium alloy powder for additive manufacturing.

10. The Ti-6Al-4V-0.25Si titanium alloy part according to claim 9, characterized in that, The Ti-6Al-4V-0.25Si titanium alloy parts have a tensile strength of not less than 1250 MPa at room temperature, a yield strength of not less than 1100 MPa at room temperature, and an elongation of not less than 8%. Furthermore, the Ti-6Al-4V-0.25Si titanium alloy parts have a tensile strength of not less than 1000 MPa, a yield strength of not less than 850 MPa, and an elongation of not less than 9% at a temperature of 400℃.

11. The Ti-6Al-4V-0.25Si titanium alloy part according to claim 10, characterized in that, The Ti-6Al-4V-0.25Si titanium alloy parts have a tensile strength at room temperature greater than or equal to 1250 MPa and less than or equal to 1450 MPa, a room temperature yield strength greater than or equal to 1100 MPa and less than or equal to 1300 MPa, and an elongation greater than or equal to 8% and less than or equal to 14%; and the Ti-6Al-4V-0.25Si titanium alloy parts have a tensile strength at 400℃ greater than or equal to 1000 MPa and less than or equal to 1120 MPa, a yield strength greater than or equal to 850 MPa and less than or equal to 950 MPa, and an elongation greater than or equal to 9% and less than or equal to 13%.

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