A method for improving the microstructure uniformity and / or mechanical properties of Ti-Ta alloy
Ti-Ta alloys were prepared by 3D printing a mixture of Ti powder and TaH powder. The dehydrogenation reaction of TaH was used to form lattice defects, which solved the problem of uneven distribution of Ta element and improved the microstructure uniformity and mechanical properties of Ti-Ta alloys, making them suitable for biomedical materials.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- HUAZHONG UNIV OF SCI & TECH
- Filing Date
- 2024-01-26
- Publication Date
- 2026-06-02
AI Technical Summary
In existing technologies, the Ta element cannot be uniformly distributed during the preparation of Ti-Ta alloys, resulting in uneven microstructure. Furthermore, traditional processes are cumbersome and costly, making it difficult to meet the needs of biomedical materials.
Ti-Ta alloys were prepared by mixing Ti powder and TaH powder and then using 3D printing. The dehydrogenation reaction of H atoms in TaH formed lattice defects, providing ion migration channels and enabling uniform diffusion of Ta and Ti to form a uniform microstructure.
It significantly improves the microstructure uniformity and mechanical properties of Ti-Ta alloys, increases tensile strength by more than 20%, and enhances biocompatibility, making it suitable for customized biomedical materials.
Smart Images
Figure CN117921031B_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of 3D printing technology for metallic materials, and more specifically, relates to a method for improving the microstructure uniformity and / or mechanical properties of Ti-Ta alloys. Background Technology
[0002] Titanium and its alloys have a wide range of applications and promising future in biomedical materials due to their good biocompatibility, mechanical properties, and excellent corrosion resistance. Currently, CP-Ti (pure titanium) and Ti-6Al-4V are commonly used in medical implant materials. However, while commercially available pure titanium (CP-Ti) possesses good ductility and biocompatibility, its low strength and poor wear resistance limit its application in medical engineering. In contrast, although Ti-6Al-4V has superior mechanical properties compared to CP-Ti, its Al and V content can lead to biotoxicity after prolonged implantation, causing potential harm to the human body. Therefore, developing titanium alloy materials with low biotoxicity and mechanical properties suitable for implantation is of great significance. Research on new titanium alloy systems has revealed that Ti-Ta alloys not only lack biotoxicity but also possess a low elastic modulus of 60-80 GPa, approximately half that of Ti-6Al-4V, attracting considerable attention from researchers.
[0003] However, due to the significant differences in melting point and density between Ti and Ta (Ti: melting point 1668℃, density 4.51 g / cm³),... 3 Ta: 2996℃, density 16.60 g / cm³ 3 The presence of Ta and Ti powders during alloying can lead to element segregation, posing a significant challenge to the preparation of uniformly structured Ti-Ta alloys. Traditional processes require repeated melting (more than eight times) to achieve a relatively uniform Ti-Ta alloy, resulting in lengthy, cumbersome, and costly processes that severely limit its practical application and development. In recent years, with the advancement of additive manufacturing technology, researchers have begun experimenting with mixing pure Ta and pure Ti powders uniformly before using laser cladding 3D printing to obtain Ti-Ta alloy bulk parts. This significantly simplifies the preparation process and allows for the direct production of medical-grade Ti-Ta alloy materials that meet patient shape requirements. However, this method also faces the challenge of uniform Ta distribution within Ti. Summary of the Invention
[0004] In view of the shortcomings of the prior art, the purpose of this application is to provide a method for preparing Ti-Ta alloy with uniform microstructure and excellent mechanical properties, aiming to solve the problem that Ta cannot be uniformly distributed in Ti during the preparation of Ti-Ta alloy in the prior art.
[0005] To achieve the above objectives, this application provides a method for improving the microstructure uniformity and / or mechanical properties of Ti-Ta alloys. The method involves uniformly mixing Ti powder and TaH powder and then preparing the Ti-Ta alloy using 3D printing. During the 3D printing sintering process, H atoms in TaH undergo a dehydrogenation reaction, forming lattice defects in the surrounding alloy microstructure. This provides ion migration channels for the mutual diffusion of Ta and Ti ions to form a uniform microstructure, ultimately resulting in a Ti-Ta alloy with a uniform microstructure.
[0006] Preferably, the method includes the following steps:
[0007] (1) Thoroughly mix Ti powder and TaH powder, and then mix them in a vacuum or inert gas atmosphere to obtain a uniformly mixed powder.
[0008] (2) The uniformly mixed powder is vacuum dried to obtain a dry mixed powder;
[0009] (3) The dried mixed powder is 3D printed under conditions where the oxygen content is less than 1000ppm to obtain Ti-Ta alloy bulk material.
[0010] Preferably, the Ti powder in step (1) has a particle size range of 15-105 μm, and the TaH powder has a particle size range of 10-50 μm.
[0011] Preferably, the powder mixing in step (1) is carried out in a powder mixer for 8-24 hours.
[0012] Preferably, the mass percentage of TaH powder in the uniformly mixed powder in step (1) is 5%-20%.
[0013] Preferably, the vacuum drying in step (2) is performed at a temperature of 70-80°C for 1-3 hours.
[0014] Preferably, step (3) uses laser 3D printing or electron beam 3D printing.
[0015] Preferably, the 3D printing in step (3) is laser 3D printing with a printing power of 200-500w and a scanning speed of 600-1000mm / s; or the 3D printing is electron beam 3D printing with an electron beam current of 15-25mA and a scanning speed of 5-15m / s.
[0016] According to another aspect of this application, a Ti-Ta alloy prepared by the method is provided.
[0017] According to another aspect of this application, a biomedical Ti-Ta alloy is provided, which is prepared using the Ti-Ta alloy.
[0018] In summary, compared with the prior art, the technical solutions conceived in this application have the following main technical advantages:
[0019] (1) In this application, TaH alloy powder replaces the existing Ta powder and is added to spherical CP-Ti powder for uniform mixing. Then, laser 3D printing technology is used to prepare a biomedical Ti-Ta alloy with uniform microstructure and meeting the requirements of human mechanical properties. During the 3D printing sintering process, the H atoms in TaH undergo a dehydrogenation reaction, which creates a large number of lattice defects in the surrounding alloy structure. This provides ion migration channels for the mutual diffusion of high-melting-point Ta ions and Ti ions to form a uniform microstructure, ultimately obtaining a Ti-Ta alloy with uniform microstructure.
[0020] (2) This application uses micron-sized TaH alloy powder to prepare biomedical Ti-Ta alloy. Compared with the original method of using pure Ta to prepare biomedical Ti-Ta alloy, it can significantly improve the diffusion ability of high melting point Ta in Ti, thereby obtaining Ti-Ta alloy with a more uniform microstructure.
[0021] (3) Because the biomedical Ti-Ta alloy prepared by adding TaH has a more uniform microstructure, the tensile strength can be increased by more than 20% compared with the original method of directly adding pure Ta; compared with the biomedical pure Ti currently used in the market, the tensile strength can be increased by more than 38%.
[0022] (4) Since the biomedical Ti-Ta alloy prepared by adding TaH has a more uniform microstructure, it is expected to have better biocompatibility than the original method of preparing biomedical Ti-Ta alloy using pure Ta and the pure Ti human implant materials currently used in the market. Attached Figure Description
[0023] Figure 1 Stress-strain diagrams of tensile tests on laser 3D printed blocks for Comparative Example 1 (pure Ti), Comparative Example 2 (with Ta), and Example 1 (with TaH alloy powder).
[0024] Figure 2 Backscattering diagrams and EDS elemental distribution maps of laser 3D printed blocks were prepared for Comparative Example 1 (pure Ti), Comparative Example 2 (with added Ta), and Example 1 (with added TaH alloy powder). Detailed Implementation
[0025] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.
[0026] This application provides a method for improving the microstructure uniformity and / or mechanical properties of Ti-Ta alloys, which also belongs to a method for preparing Ti-Ta alloys. Ti powder and TaH powder are mixed uniformly and then Ti-Ta alloys are prepared by 3D printing. It is speculated that during the 3D printing sintering process, H atoms in TaH will undergo a dehydrogenation reaction. The hydrogen atoms will destroy the original crystal structure. In the continuous hydrogen absorption and dehydrogenation reaction, a large number of lattice defects are formed in the surrounding alloy structure, thereby providing ion migration channels for the mutual diffusion of high-melting-point Ta ions and Ti ions to form a uniform microstructure, and finally obtaining a Ti-Ta alloy with a uniform microstructure.
[0027] Specifically, during laser (or electron beam) forming, TaH alloy powder undergoes a dehydrogenation reaction. The free H ions, during precipitation, cause numerous lattice defects in the surrounding alloy structure. These lattice defects provide channels for the interdiffusion of Ti and Ta, allowing high-melting-point Ta to be uniformly distributed within Ti and forming a Ti-Ta alloy with a uniform microstructure. Ta, as a stabilizing element of the β phase of Ti and its ability to promote the proliferation and differentiation of human bone cells, allows for the use of TaH to prepare biomedical Ti-Ta alloys with uniform microstructures, significantly improving their tensile strength and enhancing their ability to promote bone cell proliferation and differentiation. Compared to existing technologies for preparing biomedical Ti-Ta alloys, the method presented in this application is simpler and more effective, suitable for practical production applications. Compared to Ti-Ta alloys prepared from pure Ta, the method provided by this invention not only optimizes the microstructure uniformity of Ti-Ta alloys and achieves a tensile strength increase of over 20%, but also incorporates the technological advantages of 3D printing, enabling the customization of implant materials to meet the needs of medical patients, thus increasing the flexibility and practicality of biomedical Ti-Ta alloys.
[0028] In some embodiments, the method for preparing the Ti-Ta alloy provided in this application includes the following steps:
[0029] (1) Thoroughly mix Ti powder and TaH powder, and then mix them in a vacuum or inert gas atmosphere to obtain a uniformly mixed powder.
[0030] (2) The uniformly mixed powder is vacuum dried to obtain a dry mixed powder;
[0031] (3) The dried mixed powder was 3D printed under conditions where the oxygen content was less than 1000 ppm to obtain Ti-Ta alloy bulk material.
[0032] This application uses Ti powder and TaH powder to prepare Ti-Ta alloys, and the powder particle size is selected to meet the requirements of 3D printing. In some embodiments, the Ti powder is spherical titanium powder (abbreviated as CP-Ti spherical powder); in preferred embodiments, the particle size range of the Ti powder is 15-105 μm, and the particle size range of the TaH powder is 10-50 μm.
[0033] In some embodiments, the powder mixing in step (1) is carried out in a powder mixer for 8-24 hours. The powder mixer is a ball mill or an air jet mill. The mixing time is long enough to ensure uniform mixing.
[0034] In some embodiments, step (2) vacuum drying is performed at a temperature of 70-80°C for 1-3 hours to ensure the dryness of the powder during 3D printing and the powder flowability during the powder spreading process. This application ensures that the TaH alloy powder and Ti powder have less direct contact time with air during powder mixing and drying, thereby reducing their oxygen and moisture content.
[0035] This application allows for the adjustment of the mass ratio of raw material Ti powder and TaH powder as needed to prepare Ti-Ta alloys with a target atomic ratio. In some embodiments, the mass fraction of TaH powder in step (1) in the mixed powder is 5-20%. In the embodiments of this application, the amount of TaH powder added is fixed at 10% by mass to explain the advantages of using TaH over Ta in preparing biomedical Ti-Ta alloys.
[0036] This application describes 3D printing of dried mixed powder under conditions with an oxygen content of less than 1000 ppm. In some embodiments, the 3D printing is laser 3D printing with a printing power of 200-500 W and a scanning speed of 600-1000 mm / s; or the 3D printing is electron beam 3D printing with an electron beam current of 15-25 mA and a scanning speed of 5-15 m / s.
[0037] This application provides a method for improving the microstructure uniformity and mechanical properties of Ti-Ta alloys in some embodiments. The method involves mixing TaH alloy powder with a particle size range of 10-50 μm and spherical pure Ti powder with a particle size range of 15-105 μm in a powder mixer, and then using laser cladding 3D printing technology to fabricate biomedical Ti-Ta alloy materials of specific shapes. It is inferred that during laser sintering, the TaH alloy powder undergoes a dehydrogenation reaction. The free H ions, during precipitation, cause numerous lattice defects in the surrounding alloy structure. These lattice defects provide channels for the interdiffusion of Ti and Ta, resulting in the uniform distribution of high-melting-point Ta within the Ti and the formation of a microstructure-uniform Ti-Ta alloy. Ta, as a stabilizing element of the β phase of Ti, and its ability to promote the proliferation and differentiation of human bone cells, allows the use of TaH to prepare biomedical Ti-Ta alloys with uniform microstructures, significantly increasing the relative content of β-Ti in the Ti-Ta alloy and thus substantially improving its tensile strength.
[0038] The following is an example:
[0039] Comparative Example 1
[0040] (1) Vacuum seal CP-Ti spherical powder with a particle size range of 20-50μm and place it into a glove box.
[0041] (2) Weigh 2000g of spherical CP-Ti powder in the glove box, put it into an aluminum can, seal the lid, and take it out of the glove box.
[0042] (3) Pour the aluminum can powder into the mixer and mix for 12 hours. Then put the powder into the vacuum drying oven and dry at 70°C for 2 hours.
[0043] (4) Place the uniformly mixed powder into the laser cladding 3D printer, use Ar gas to purge the chamber to ensure that the oxygen content in the chamber is less than 1000ppm, and use laser sintering printing with laser power of 400w and scanning speed of 800mm / s to obtain Ti alloy block material of the required shape.
[0044] Comparative Example 2
[0045] (1) Vacuum seal Ta alloy powder with a particle size range of 10-50μm and CP-Ti spherical powder with a particle size range of 20-50μm into a glove box.
[0046] (2) Weigh 200g of Ta alloy powder and 1800g of spherical CP-Ti powder in the glove box, put them into an aluminum can, seal the lid, and take them out of the glove box.
[0047] (3) Pour the aluminum can powder into the mixer and mix for 12 hours; then put the evenly mixed powder into the vacuum drying oven and dry at 70°C for 2 hours.
[0048] (4) Place the uniformly mixed powder into the laser cladding 3D printer, purge the chamber with Ar gas to ensure that the oxygen content in the chamber is less than 1000ppm, and perform laser sintering printing with laser power of 400w and scanning speed of 800mm / s to obtain the desired Ti-Ta alloy block material.
[0049] Example 1
[0050] (1) Vacuum seal TaH alloy powder with a particle size range of 20-30 μm and CP-Ti spherical powder with a particle size range of 20-50 μm into a glove box.
[0051] (2) Weigh 200g of TaH alloy powder and 1800g of spherical CP-Ti powder in the glove box, put them into an aluminum can, seal the can, and then take it out of the glove box.
[0052] (3) Tie the aluminum can to the outside of the powder mixer, start the mixer, and mix for 12 hours; then put the evenly mixed powder into the vacuum drying oven and dry at 70°C for 2 hours.
[0053] (4) Place the uniformly mixed powder into the laser cladding 3D printer, purge the chamber with Ar gas to ensure that the oxygen content in the chamber is less than 1000ppm, and perform laser sintering printing with laser power of 400w and scanning speed of 800mm / s to obtain the desired Ti-Ta alloy block material.
[0054] Example 2
[0055] (1) Vacuum seal TaH alloy powder with a particle size range of 20-30μm and CP-Ti spherical powder with a particle size range of 20-50μm into a glove box.
[0056] (2) Weigh 200g of TaH alloy powder and 1800g of spherical Ti powder in the glove box, put them into an aluminum can, seal the lid, and take them out of the glove box.
[0057] (3) Pour the powder from the aluminum can into a ball mill, vacuum it, and mix the powder in the ball mill for 12 hours; then put the evenly mixed powder into a vacuum drying oven and dry it at 70°C for 2 hours.
[0058] (4) Place the uniformly mixed powder into the laser 3D printer, purge the chamber with Ar gas to ensure that the oxygen content in the chamber is less than 1000ppm, and perform laser sintering printing with process parameters of laser power 400w and scanning speed 800mm / s to obtain the desired Ti-Ta alloy block material.
[0059] Example 3
[0060] (1) Vacuum seal TaH alloy powder with a particle size range of 20-30μm and CP-Ti spherical powder with a particle size range of 20-50μm and place them in a glove box.
[0061] (2) Weigh 200g of TaH alloy powder and 1800g of spherical Ti powder in the glove box, put them into an aluminum can, seal the lid, and take them out of the glove box.
[0062] (3) Pour the powder from the aluminum can into the powder mixer, and after vacuuming, the mixing time is 12 hours; then put the evenly mixed powder into the vacuum drying oven and dry it at 70°C for 2 hours.
[0063] (4) Place the uniformly mixed powder into the electron beam 3D printer, use Ar gas to clean the chamber and evacuate it to ensure that the oxygen content in the chamber is less than 1000ppm. Use the process parameters of electron beam current 16.8mA and scanning speed 5m / s to 3D print Ti-Ta alloy block material of the required shape.
[0064] The mechanical properties of the materials prepared in each embodiment and comparative example are shown in Table 1.
[0065] Table 1: Comparison of Mechanical Properties of Each Embodiment and Comparative Example
[0066]
[0067] Figure 1 The stress-strain diagrams of tensile tests on 3D printed blocks prepared by pure Ti (Comparative Example 1), Ta-added (Comparative Example 2), and TaH alloy powder (Example 1) are shown. Figure 2 Backscattering and EDS elemental distribution maps of 3D printed blocks prepared by Comparative Example 1 (pure Ti), Comparative Example 2 (with Ta), and Example 1 (with TaH alloy powder) are shown. Contents (a), (b), (c), and (d) correspond to the pure Ti printed sample of Comparative Example 1; contents (e), (f), (g), and (h) correspond to the Ta-added printed sample of Comparative Example 2; and contents (i), (j), (k), and (l) correspond to the printed sample prepared by adding TaH alloy powder to Comparative Example 2.
[0068] From the test results in Table 1 and the appendix Figure 1Compared to laser 3D printed blocks with added Ta alloy powder and pure Ti, the yield strength and tensile strength of biomedical Ti-Ta alloys prepared by adding TaH are significantly enhanced (tensile strength is increased by more than 20% compared to the original method of directly adding pure Ta; tensile strength is increased by more than 38% compared to currently used biomedical pure Ti), and it also has a lower elastic modulus, indicating some optimization of mechanical properties. Furthermore, from... Figure 2 As can be seen, when Ta is added to prepare Ti-Ta alloys, the diffusion ability of Ta is extremely low, with a diffusion width of less than 3 μm. However, when TaH is added to prepare Ti-Ta alloys, the amount of unmelted Ta is significantly reduced, and the diffusion of molten Ta is very obvious, with a diffusion width of more than 15 μm. The uniformity of the microstructure is significantly improved.
[0069] In summary, using TaH to prepare biomedical Ti-Ta alloys can result in a uniform microstructure and better mechanical properties, and the uniformly distributed Ti-Ta is expected to achieve better biocompatibility.
[0070] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the scope of protection of this application.
Claims
1. A method for improving the microstructure uniformity and / or mechanical properties of Ti-Ta alloys, characterized in that, Ti-Ta alloy was prepared by 3D printing after uniformly mixing Ti powder and TaH powder. During the 3D printing sintering process, the H atoms in TaH undergo a dehydrogenation reaction, forming lattice defects in the surrounding alloy structure. This provides ion migration channels for the mutual diffusion of Ta ions and Ti ions to form a uniform microstructure, ultimately resulting in a Ti-Ta alloy with a uniform microstructure. The method includes the following steps: (1) Thoroughly mix Ti powder and TaH powder, and then perform powder mixing in a vacuum or inert gas atmosphere to obtain a uniformly mixed powder; the particle size range of the Ti powder is 15-105 μm, and the particle size range of the TaH powder is 10-50 μm; the mass percentage of the TaH powder in the uniformly mixed powder is 5%-20%; (2) The uniformly mixed powder is vacuum dried to obtain a dry mixed powder; (3) The dried mixed powder is 3D printed under conditions where the oxygen content is less than 1000ppm to obtain Ti-Ta alloy bulk material.
2. The method as described in claim 1, characterized in that, The powder mixing in step (1) is carried out in a powder mixer for 8-24 hours.
3. The method as described in claim 1, characterized in that, The vacuum drying in step (2) is carried out at a temperature of 70-80℃ for 1-3 hours.
4. The method as described in claim 1, characterized in that, Step (3) uses laser 3D printing or electron beam 3D printing.
5. The method as described in claim 1, characterized in that, The 3D printing in step (3) is laser 3D printing with a printing power of 200-500w and a scanning speed of 600-1000mm / s; or the 3D printing is electron beam 3D printing with an electron beam current of 15-25mA and a scanning speed of 5-15 m / s.
6. The Ti-Ta alloy prepared by the method according to any one of claims 1 to 5.
7. A biomedical Ti-Ta alloy, characterized in that, It was prepared using the Ti-Ta alloy as described in claim 6.