Antibacterial Ti alloy with nano-rich Cu structure and preparation method thereof

Abstract

The application relates to an antibacterial Ti alloy with a nano-rich Cu structure and a preparation method thereof, and belongs to the technical field of antibacterial materials. The application designs an antibacterial Ti alloy with antibacterial property, low elastic modulus, high biocompatibility and good corrosion resistance by combining Ti, Mo, Hf and Cu, that is, a TiMoHfCu alloy. The alloy has the beta-Ti structure with low elastic modulus and high biocompatibility due to the addition of the Mo element, and has better corrosion resistance than pure Ti. By using the characteristics that the mixing enthalpy of Hf and Cu is lower than that of Ti and Cu, the thermodynamic characteristics that the Hf2Cu phase has higher stability, and the characteristics that Ti can completely replace Hf in the Hf2Cu phase, the composition of Ti, Hf and Cu elements is regulated, a large amount of nano-scale needle-shaped (Ti, Hf)2Cu phases are precipitated in the alloy without complex heat treatment, and thus the alloy is endowed with excellent comprehensive performance.

Description

Technical Field

[0001] This invention belongs to the field of antibacterial materials technology, and specifically relates to an antibacterial Ti alloy with a nano-Cu-rich structure and its preparation method. Background Technology

[0002] With the deepening of population aging, oral problems such as missing teeth, jawbone defects, and temporomandibular joint (TMJ) repair significantly reduce people's health and quality of life. Metal implants, due to their excellent mechanical strength and durability, play a vital role in treating these conditions. Since the mid-20th century, metal implant technology has continuously advanced, evolving from dental implants to complex maxillofacial reconstruction and orthognathic surgery, greatly improving treatment outcomes and patients' quality of life. However, the number of cases of implant failure due to bacterial infection following implant surgery remains high. Statistics show that approximately 47% of implant failures are caused by inflammatory infections. Therefore, the development of antibacterial alloys suitable for the oral environment is of great significance.

[0003] Over the past decade, dental implant restoration has become increasingly sophisticated. In the field of dental implants, traditional metal implant materials mainly include stainless steel, Co-Cr alloys, and Ti and Ti alloys. Among these, Ti and Ti alloys are considered ideal metal implant materials due to their good biocompatibility, excellent corrosion resistance, high strength, and low elastic modulus. Their elastic modulus (approximately 110 GPa) is significantly lower than that of stainless steel (260 GPa) and Co-Cr alloys (220 GPa), which helps achieve a more balanced stress distribution between the implant and bone tissue, effectively reducing bone resorption and implant loosening caused by the "stress shielding" effect. Furthermore, the inert passivation film formed on the surface of Ti and Ti alloys can prevent the erosion of corrosive ions in body fluids. However, Ti and Ti alloy implants are prone to forming an inert biofilm, resulting in poor surface bioactivity and a lack of osteoinductive effect, severely impacting the long-term survival rate of the implant. Moreover, bacterial biofilms colonizing the surface of Ti and Ti alloy implants can inhibit the effectiveness of antibiotics, increasing the difficulty of infection treatment.

[0004] Currently, Ti alloys are typically classified into α-type, near-α-type, α+β-type, metastable β-type, and β-type based on the content of β-stabilizing elements and microstructure. β-Ti alloys exhibit the best overall performance, including moderate strength, the lowest elastic modulus, and optimal biocompatibility. Mo, due to its excellent biocompatibility, weak antibacterial properties, and extremely strong β-phase structural stabilization ability, can significantly improve the mechanical properties and corrosion resistance of alloys. Hf and Ti belong to the same group of elements, have similar chemical properties, and both exhibit good biocompatibility. Cu, as an essential trace element for the human body, not only possesses excellent antibacterial properties but also promotes bone formation and wound healing. Summary of the Invention

[0005] Based on the above background, this invention combines the advantages of Ti, Mo, Hf, and Cu to design a β-type Ti alloy, namely TiMoHfCu alloy, which possesses antibacterial properties, low modulus, good biocompatibility, and corrosion resistance. Due to the addition of Mo, the alloy exhibits a low-modulus and highly biocompatible β-Ti structure, while also demonstrating superior corrosion resistance compared to pure Ti. Utilizing the lower mixing enthalpy of Hf and Cu compared to Ti and Cu, the higher thermodynamic stability of the Hf₂Cu phase, and the ability of Ti to completely replace Hf within the Hf₂Cu phase, the content of Ti, Hf, and Cu elements is controlled to precipitate a large amount of nanoscale needle-like (Ti,Hf)₂Cu phase without complex heat treatment, thereby endowing the alloy with excellent comprehensive properties.

[0006] To address the problems in the prior art, this invention provides an antibacterial Ti alloy with a nano-Cu-rich structure and its preparation method. The main objective is to obtain a Ti alloy that combines antibacterial properties, low modulus, high biocompatibility, and good corrosion resistance.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] An antibacterial Ti alloy with a nano-Cu-rich structure, the general chemical formula of the alloy being Ti. a Mo b Hf c Cu d , of which 75 <a≤86,8<b≤11,4<c≤6,0≤d≤11。

[0009] Furthermore, the antibacterial Ti alloy with a nano-Cu-rich structure contains a bulk (Ti,Hf)2Cu structure, and a large number of nanoscale needle-like (Ti,Hf)2Cu phases are distributed around the bulk (Ti,Hf)2Cu structure; the interface between the needle-like (Ti,Hf)2Cu structure and the β matrix is ​​a coherent interface.

[0010] Furthermore, the compressive yield strength of the antibacterial Ti alloy with nano-Cu-rich structure is 886–1117 MPa, and its elastic modulus is 27–38 GPa lower than that of pure Ti; the antibacterial rate against Escherichia coli adhering to the surface is not less than 97%.

[0011] Furthermore, when the Cu content is 5% (at.%), the alloy exhibits the best biocompatibility. The cell proliferation rate of MC3T3-E1Subclone14 (mouse cranial anterior osteoblast subclone 14) cells after co-culturing for 7 days is much higher than that of pure Ti, and its surface osteoblast morphology and cell density are superior to those of pure Ti.

[0012] A method for preparing an antibacterial Ti alloy with a nano-Cu-rich structure includes the following steps:

[0013] Step 1: Place sponge titanium or Ti particles into the furnace for melting, and use the oxidation reaction of Ti to absorb the residual oxygen in the furnace;

[0014] Step 2: Mix Mo flakes and Hf particles according to the atomic percentage of the target alloy composition, pre-treat them and then melt them more than twice to obtain a stable Mo and Hf master alloy, cut them into particles to obtain MoHf master alloy particles.

[0015] Step 3: Mix the MoHf intermediate alloy particles and the weighed Ti particles, placing the MoHf intermediate alloy particles on top, the Ti particles in the middle, and the Cu particles at the bottom. After pretreatment, perform melting more than twice to obtain an antibacterial Ti alloy with a nano-Cu-rich structure.

[0016] The pretreatment process in steps 1, 2, and 3 involves repeatedly rinsing the raw material metal particles or sponge titanium with argon gas in a vacuum environment; the vacuum level of the vacuum environment is less than 10. -3 Pa.

[0017] In steps 2 and 3, the metal particles are ultrasonically cleaned with alcohol to remove oil stains and then dried in a fume hood.

[0018] In step 2, the raw material metal particles are small cylinders with a diameter of 1 mm and a length of 1 mm, resulting in an atomic ratio of Mo to Hf of 2:1 in the MoHf intermediate alloy particles.

[0019] In step 1, the melting temperature is 1700-1800℃, the melting time is 50-65s, and the melting is performed once.

[0020] In step 2, the melting temperature is 2400-2800℃, and the mixture is flipped and remelted twice, with each melting session lasting no less than 60 seconds.

[0021] The melting temperature in step 3 is 1700-2100℃. After flipping, the material is remelted twice, with each melting session lasting no less than 60 seconds.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] This invention utilizes the low binding enthalpy of Hf and Cu to regulate the formation of needle-like nanoscale (Ti,Hf)₂Cu in Cu-containing β-Ti alloys. The interface between this (Ti,Hf)₂Cu and the β-matrix exhibits a coherent relationship, resulting in a high degree of lattice matching between the two phases, more stable atomic bonding, and a stable interface that is less prone to interface migration or breakage. Simultaneously, the regular and compact atomic arrangement at the coherent interface reduces voids and defects, thereby reducing the penetration of corrosive media and improving the material's corrosion resistance.

[0024] The Cu content and morphology in Ti alloys significantly affect their mechanical properties, antibacterial properties, and biocompatibility. Increasing the Cu content improves the alloy's strength but may decrease its elongation. Adding more than 5 wt.% Cu to the alloy yields stable antibacterial effects, but excessive Cu may release excess Cu ions, increasing cytotoxicity. Compared to solid-solution Cu, precipitation strengthening effects of intermetallic phases such as Ti₂Cu are significant, while also possessing stronger antibacterial capabilities. Furthermore, the morphology of intermetallic phases such as Ti₂Cu also affects the alloy's mechanical properties; studies have shown that needle-shaped Ti₂Cu is more beneficial for improving alloy strength than spherical ones. Other studies have confirmed that the antibacterial efficiency of nanoneedle-shaped Ti₂Cu phases can be up to twice that of spherical ones.

[0025] Compared to existing Cu-containing antibacterial Ti alloys, the alloy matrix of this invention has a β-Ti structure instead of an α-Ti structure, resulting in a lower elastic modulus. Utilizing the unique thermodynamic properties of Hf, this invention designs an antibacterial Ti alloy that can precipitate nanoscale (Ti,Hf)₂Cu antibacterial phases without complex heat treatment. This structure exhibits superior antibacterial performance compared to spherical Cu-rich phases. In contrast, conventional Cu-containing antibacterial Ti alloys require complex failure and solution treatments to obtain nanoscale (Ti,Hf)₂Cu antibacterial phases. Attached Figure Description

[0026] Figure 1 These are BSD and EDS images of the microstructure of the TiMoHfCu antibacterial Ti alloy prepared in Examples 1-3 of this invention;

[0027] Figure 2 This is a transmission electron microscope image of the Cu-rich precipitate phase of the TiMoHfCu antibacterial Ti alloy prepared in Example 3 of the present invention;

[0028] Figure 3 This is a significant comparison chart of the antibacterial rate between pure Ti samples and the TiMoHfCu antibacterial Ti alloys prepared in Examples 1-3 of this invention;

[0029] Figure 4 These are fluorescence staining images of the cytoskeleton of pure Ti samples and the TiMoHfCu antibacterial Ti alloys prepared in Examples 1-3 of this invention, taken 1 day apart.

[0030] Figure 5 The graph shows the significant difference in elastic modulus between the pure Ti sample and the TiMoHfCu antibacterial Ti alloy prepared in Examples 1-3 of this invention. Detailed Implementation

[0031] To explain the present invention in more detail, it will now be described in conjunction with the accompanying drawings and specific embodiments. It should be noted that these embodiments are only used to describe specific applications of the invention and do not limit its scope. In the following embodiments, unless otherwise specified, the operations are generally performed according to standard experimental methods.

[0032] Example 1

[0033] This invention provides a TiMoHfCu antibacterial Ti alloy and its preparation method, with the general chemical formula Ti. 85 Mo 10 Hf5Cu0 (at.%), based on the chemical formula of the aforementioned antibacterial Ti alloy, calculate the addition amounts of elemental Ti, Mo, and Hf raw materials. The purity of the elemental Ti, Mo, and Hf raw materials used must all reach 99% (wt.%) or higher. The purity of the Ti particles or sponge titanium required for oxygen adsorption in the furnace only needs to reach 98% (wt.%) or higher. The process includes the following steps:

[0034] Step 1: Remove oxygen from the furnace

[0035] Before each melting operation, sponge titanium or Ti particles are placed together with the alloy to be melted into a water-cooled copper crucible inside the magnetic levitation induction melting furnace. First, the system is evacuated to below 10... -3 The pressure is increased to ensure almost complete removal of gases; then, melting begins under an argon protective atmosphere of 1.2 bar, which allows Ti to absorb residual oxygen in the furnace. The temperature is maintained at 1750°C and the time is controlled at 60 seconds; this melting step is performed only once.

[0036] Step 2: Preparation of MoHf master alloy

[0037] Mo flakes and Hf particles were cleaned, degreased, and dried using ultrasonic cleaning with alcohol. They were then mixed in a 2:1 ratio based on atomic percentage. The weighed Mo flakes and Hf particles were placed into a water-cooled copper crucible in a magnetic levitation induction melting furnace, and the furnace was evacuated until the pressure dropped below 10°C. - 3 After achieving a vacuum of Pa, the alloy is melted under an argon atmosphere of 1.2 bar at a temperature of 2500°C for 60 seconds. To ensure uniform composition, the alloy is turned over and melted twice to obtain a stable MoHf master alloy. The MoHf master alloy is then cut into particles.

[0038] Step 3: Preparation of the final alloy

[0039] Mix the MoHf master alloy particles and the weighed Ti particles, placing the MoHf master alloy particles on top and the Ti particles at the bottom. Place this mixture into a water-cooled copper crucible in a magnetic levitation induction melting furnace, and evacuate the furnace until the pressure drops below 10°C.-3 After achieving a vacuum of 1 Pa, the material was melted under an argon atmosphere of 1.2 bar at a temperature of 1900℃ for 60 seconds. To ensure uniform composition, the material was turned over and melted twice to obtain a bone-promoting TiMoHf antibacterial Ti alloy material.

[0040] Example 2

[0041] This invention provides a TiMoHfCu antibacterial Ti alloy and its preparation method, with the general chemical formula Ti. 80.75 Mo 9.5 Hf 4.75 Cu5 (at.%), calculate the addition amounts of elemental Ti, Mo, and Hf raw materials according to the chemical formula of the aforementioned antibacterial Ti alloy. The purity of the elemental Ti, Mo, and Hf raw materials used must all reach 99% (wt.%) or higher. The purity of the Ti particles or sponge titanium required for oxygen adsorption in the furnace only needs to reach 98% (wt.%) or higher. The process includes the following steps:

[0042] Step 1: Remove oxygen from the furnace

[0043] Before each melting operation, sponge titanium or Ti particles are placed together with the alloy to be melted into a water-cooled copper crucible inside the magnetic levitation induction melting furnace. First, the system is evacuated to below 10... -3 The pressure is increased to ensure almost complete removal of gases. Melting then begins under an argon protective atmosphere of 1.2 bar, allowing Ti to absorb residual oxygen in the furnace. The melting process is maintained at 1750°C for 60 seconds, and this melting step is performed only once.

[0044] Step 2: Preparation of MoHf master alloy

[0045] Mo flakes and Hf particles were cleaned, degreased, and dried using ultrasonic cleaning with alcohol. They were then mixed in a 2:1 ratio based on atomic percentage. The weighed Mo flakes and Hf particles were placed into a water-cooled copper crucible in a magnetic levitation induction melting furnace, and the furnace was evacuated until the pressure dropped below 10°C. - 3 After achieving a vacuum of Pa, the alloy is melted under an argon atmosphere of 1.2 bar at a temperature of 2500°C for 60 seconds. To ensure uniform composition, the alloy is turned over and melted twice to obtain a stable MoHf master alloy. The MoHf master alloy is then cut into particles.

[0046] Step 3: Preparation of the final alloy

[0047] Mix the MoHf master alloy particles and the weighed Ti particles, placing the MoHf master alloy particles on top, the Ti alloy particles in the middle, and the Cu particles at the bottom. Place this mixture into a water-cooled copper crucible in a magnetic levitation induction melting furnace, and evacuate the furnace until the pressure drops below 10°C. -3 After achieving a vacuum of 1800 Pa, melting was carried out under an argon atmosphere of 1.2 bar at a temperature of 1900℃ for 60 seconds. To ensure uniform composition, the melting process was repeated twice by turning the sample to obtain Ti. 80.75 Mo 9.5 Hf 4.75 Cu5(at.%) antibacterial Ti alloy material.

[0048] Example 3

[0049] This invention provides a TiMoHfCu antibacterial Ti alloy and its preparation method, with the general chemical formula Ti. 76.5 Mo9Hf 4.5 Cu 10 (at.%), calculate the amount of Ti, Mo, and Hf elemental raw materials to be added according to the chemical formula of the antibacterial Ti alloy mentioned above. The purity of the Ti, Mo, and Hf elemental raw materials used must all reach 99% (wt.%) or higher. The purity of the Ti particles or sponge titanium required for oxygen in the adsorption furnace only needs to reach 98% (wt.%) or higher. The process includes the following steps:

[0050] Step 1: Remove oxygen from the furnace

[0051] Before each melting operation, sponge titanium or Ti particles are placed together with the alloy to be melted into a water-cooled copper crucible inside the magnetic levitation induction melting furnace. First, the system is evacuated to below 10... -3 The pressure is increased to ensure almost complete removal of gases. Melting then begins under an argon protective atmosphere of 1.2 bar, allowing Ti to absorb residual oxygen in the furnace. The melting process is maintained at 1750°C for 60 seconds, and this melting step is performed only once.

[0052] Step 2: Preparation of MoHf master alloy

[0053] Mo flakes and Hf particles were cleaned, degreased, and dried using ultrasonic cleaning with alcohol. They were then mixed in a 2:1 ratio based on atomic percentage. The weighed Mo flakes and Hf particles were placed into a water-cooled copper crucible in a magnetic levitation induction melting furnace, and the furnace was evacuated until the pressure dropped below 10°C. - 3 After achieving a vacuum of Pa, the alloy is melted under an argon atmosphere of 1.2 bar at a temperature of 2500°C for 60 seconds. To ensure uniform composition, the alloy is turned over and melted twice to obtain a stable MoHf master alloy. The MoHf master alloy is then cut into particles.

[0054] Step 3: Preparation of the final alloy

[0055] Mix the MoHf master alloy particles and the weighed Ti particles, placing the MoHf master alloy particles on top, the Ti particles in the middle, and the Cu particles at the bottom. Place this mixture into a water-cooled copper crucible in a magnetic levitation induction melting furnace, and evacuate the furnace until the pressure drops below 10°C. -3 After achieving a vacuum of 1800 Pa, melting was carried out under an argon atmosphere of 1.2 bar at a temperature of 1900℃ for 60 seconds. To ensure uniform composition, the melting process was repeated twice by turning the sample to obtain Ti. 76.5 Mo9Hf 4.5 Cu 10 (at.%) Antibacterial Ti alloy material.

[0056] Example 4

[0057] This invention provides a TiMoHfCu antibacterial Ti alloy and its preparation method, with the general chemical formula Ti. 85 Mo 10 Hf5Cu0 (at.%), based on the chemical formula of the aforementioned antibacterial Ti alloy, the amounts of Ti, Mo, and Hf elemental raw materials added were calculated. The purity of the Ti and Hf elemental raw materials used was both above 99% (wt.%), and the added TB7 (Ti 80 Mo 20 The alloy (at%) must meet the requirements of GB / T 3620.1-2016. The purity of the Ti particles or sponge titanium required for oxygen adsorption in the furnace should reach 98% (wt.%) or higher. The process includes the following steps:

[0058] Step 1: Remove oxygen from the furnace

[0059] Before each melting operation, sponge titanium or Ti particles are placed together with the alloy to be melted into a water-cooled copper crucible inside the magnetic levitation induction melting furnace. First, the system is evacuated to below 10... -3 The pressure is increased to ensure almost complete removal of gases. Melting then begins under an argon protective atmosphere of 1.2 bar, allowing Ti to absorb residual oxygen in the furnace. The melting process is maintained at 1750°C for 60 seconds, and this melting step is performed only once.

[0060] Step 2: Preparation of the final alloy

[0061] TB7 alloy particles were mixed with Ti and Hf particles in a mass ratio of 50:35:16, with Hf particles placed on top, TB7 particles in the middle, and Ti particles at the bottom. This mixture was then placed in a water-cooled copper crucible within a magnetic levitation induction melting furnace, and the furnace was evacuated until the pressure dropped below 10°C.-3 After achieving a vacuum of 1 Pa, the material was melted under an argon atmosphere of 1.2 bar at a temperature of 1900℃ for 60 seconds. To ensure uniform composition, the material was turned over and melted twice to obtain a bone-promoting TiMoHf antibacterial Ti alloy material.

[0062] Example 5

[0063] This invention provides a TiMoHfCu antibacterial Ti alloy and its preparation method, with the general chemical formula Ti. 80.75 Mo 9.5 Hf 4.75 Cu5 (at.%), based on the chemical formula of the aforementioned antibacterial Ti alloy, the amounts of Ti, Mo, and Hf elemental raw materials added were calculated. The purity of the Ti and Hf elemental raw materials used was both above 99% (wt.%), and the added TB7 (Ti 80 Mo 20 The alloy (at%) must meet the requirements of GB / T 3620.1-2016. The purity of the Ti particles or sponge titanium required for oxygen adsorption in the furnace should reach 98% (wt.%) or higher. The process includes the following steps:

[0064] Step 1: Remove oxygen from the furnace

[0065] Before each melting operation, sponge titanium or Ti particles are placed together with the alloy to be melted into a water-cooled copper crucible inside the magnetic levitation induction melting furnace. First, the system is evacuated to below 10... -3 The pressure is increased to ensure almost complete removal of gases. Melting then begins under an argon protective atmosphere of 1.2 bar, allowing Ti to absorb residual oxygen in the furnace. The melting process is maintained at 1750°C for 60 seconds, and this melting step is performed only once.

[0066] Step 2: Preparation of the final alloy

[0067] TB7 alloy particles were mixed with Ti, Hf, and Cu particles in a mass ratio of 47.8:32.5:14.3:5.3. Hf particles were placed on top, TB7 and Ti particles in the middle, and Cu particles at the bottom. This mixture was then placed in a water-cooled copper crucible within a magnetic levitation induction melting furnace. The furnace was evacuated until the air pressure dropped below 10°C. -3 After achieving a vacuum of 1800 Pa, melting was carried out under an argon atmosphere of 1.2 bar at a temperature of 1900℃ for 60 seconds. To ensure uniform composition, the melting process was repeated twice by turning the sample to obtain Ti. 80.75 Mo 9.5 Hf 4.75 Cu5(at.%) antibacterial Ti alloy material.

[0068] Example 6

[0069] This invention provides a TiMoHfCu antibacterial Ti alloy and its preparation method, with the general chemical formula Ti. 76.5 Mo9Hf 4.5 Cu 10 (at.%), based on the chemical formula of the aforementioned antibacterial Ti alloy, the amounts of Ti, Mo, and Hf elemental raw materials added were calculated. The purity of the Ti and Hf elemental raw materials used was both above 99% (wt.%), and the added TB7 (Ti 80 Mo 20 The alloy (at%) must meet the requirements of GB / T 3620.1-2016. The purity of the Ti particles or sponge titanium required for oxygen adsorption in the furnace should reach 98% (wt.%) or higher. The process includes the following steps:

[0070] Step 1: Remove oxygen from the furnace

[0071] Before each melting operation, sponge titanium or Ti particles are placed together with the alloy to be melted into a water-cooled copper crucible inside the magnetic levitation induction melting furnace. First, the system is evacuated to below 10... -3 The pressure is increased to ensure almost complete removal of gases. Melting then begins under an argon protective atmosphere of 1.2 bar, allowing Ti to absorb residual oxygen in the furnace. The melting process is maintained at 1750°C for 60 seconds, and this melting step is performed only once.

[0072] Step 2: Preparation of the final alloy

[0073] TB7 alloy particles were mixed with Ti, Hf, and Cu particles in a mass ratio of 45.5:30.4:13.5:10.7. Hf particles were placed on top, TB7 and Ti particles in the middle, and Cu particles at the bottom. This mixture was then placed in a water-cooled copper crucible within a magnetic levitation induction melting furnace. The furnace was evacuated until the air pressure dropped below 10°C. -3 After achieving a vacuum of 1800 Pa, melting was carried out under an argon atmosphere of 1.2 bar at a temperature of 1900℃ for 60 seconds. To ensure uniform composition, the melting process was repeated twice by turning the sample to obtain Ti. 76.5 Mo9Hf 4.5 Cu 10 (at.%) Antibacterial Ti alloy material.

[0074] Figure 1a1, a2, and a3 are backscattered electron microscopy (BSE) images of the microstructure of the TiMoHfCu antibacterial Ti alloys prepared in Examples 1-3 of this invention with the addition of 0%, 5%, and 10% Cu, respectively. a4 is a magnified view of a3, and b is the energy dispersive spectroscopy (EDS) analysis of a4. It can be seen that segregation occurs at the dendrite arms with increasing Cu content. EDS line scan analysis of the segregation at the dendrite arms shows a significant increase in Cu content at the dendrite arms, with the Cu content at point 2 approaching 33%, therefore the composition at this point is (Ti, Hf)₂Cu.

[0075] Figure 2 The images show the TEM bright-field morphology and EDS composition analysis of the Cu-rich region of the TiMoHfCu antibacterial Ti alloy prepared in Example 3 of this invention. Numerous nanoscale needle-like structures are visible surrounding the bulk (Ti,Hf)₂Cu. Analysis of the needle-like structure, specifically at position "1", reveals atomic ratios of Ti, Mo, Hf, and Cu of 62.4, 0.6, 7.3, and 29.6, respectively. The Cu content is close to one-third, therefore the needle-like structure is also (Ti,Hf)₂Cu.

[0076] Figure 3 Examples 1 to 3 of the present invention demonstrate the antibacterial rates of the TiMoHfCu antibacterial Ti alloy with the addition of 0%, 5%, and 10% copper (Cu), respectively, which are 30.8%, 57.7%, and 97.4%.

[0077] Figure 4 (a) illustrates the cell adhesion properties of the TiMoHfCu antibacterial Ti alloy in Examples 1 to 3 of the present invention with the addition of 0%, 5%, and 10% copper (Cu). Compared to Ti, the TiMoHfCu antibacterial Ti alloy surface exhibits easier cell adhesion, meaning it promotes early adhesion and colonization of osteoblasts, thus facilitating early osseointegration around the implant. This may be due to the unique structure of the alloy surface increasing the hydrophilicity of the material surface.

[0078] Figure 5 The elastic modulus of the TiMoHfCu antibacterial Ti alloy in Examples 1 to 3 of this invention with the addition of 0%, 5%, and 10% copper (Cu) is shown, with values ​​of 91.92 GPa, 94.08 GPa, and 103.48 GPa, respectively. Compared with Ti, the TiMoHfCu antibacterial Ti alloy is closer to the elastic modulus of tooth enamel in elderly patients (91.1 ± 6.5) GPa, which means that the implant can effectively protect the tooth structure under stress and prevent stress shielding, etc.

Claims

1. An antibacterial Ti alloy with a nano-Cu-rich structure, characterized in that, The general chemical formula of the alloy is Ti. a Mo b Hf c Cu d , of which 75 a ≤86, 8< b ≤11, 4< c ≤6, 0≤ d ≤11; The antibacterial Ti alloy with a nano-Cu-rich structure contains a bulk (Ti,Hf)2Cu structure, and a large number of nanoscale needle-like (Ti,Hf)2Cu phases are distributed around the bulk (Ti,Hf)2Cu structure; the interface between the needle-like (Ti,Hf)2Cu structure and the β matrix is ​​a coherent interface.

2. The antibacterial Ti alloy with a nano-Cu-rich structure according to claim 1, characterized in that, The compressive yield strength of the antibacterial Ti alloy with nano-Cu-rich structure is 886~1117 MPa, and the elastic modulus is 27~38 GPa lower than that of pure Ti; the antibacterial rate against Escherichia coli adhering to the surface is not less than 97%.

3. A method for preparing an antibacterial Ti alloy with a nano-Cu-rich structure as described in any one of claims 1-2, characterized in that, Includes the following steps: Step 1: Place sponge titanium or Ti particles into the furnace for melting, and use the oxidation reaction of Ti to absorb the residual oxygen in the furnace; Step 2: Mix Mo flakes and Hf particles according to the atomic percentage of the target alloy composition, pre-treat them and then melt them more than twice to obtain a stable Mo and Hf master alloy, cut them into particles to obtain MoHf master alloy particles. Step 3: Mix the MoHf intermediate alloy particles and the weighed Ti particles, placing the MoHf intermediate alloy particles on top, the Ti particles in the middle, and the Cu particles at the bottom. After pretreatment, perform melting more than twice to obtain an antibacterial Ti alloy with a nano-Cu-rich structure.

4. The method for preparing an antibacterial Ti alloy with a nano-Cu-rich structure according to claim 3, characterized in that, The pretreatment process in steps 2 and 3 involves a vacuum environment with a vacuum level below 10. -3 Pa.

5. The method for preparing an antibacterial Ti alloy with a nano-Cu-rich structure according to claim 3, characterized in that, In step 2, the atomic ratio of Mo to Hf in the obtained MoHf intermediate alloy particles is 2:

1.

6. The method for preparing an antibacterial Ti alloy with a nano-Cu-rich structure according to claim 3, characterized in that, In step 1, the melting temperature is 1700~1800 ℃, the melting time is 50~65 s, and the melting is done once.

7. The method for preparing an antibacterial Ti alloy with a nano-Cu-rich structure according to claim 3, characterized in that, In step 2, the melting temperature is 2400~2800 ℃, and the melting is repeated twice after being turned over, with each melting time not less than 60 s.

8. The method for preparing an antibacterial Ti alloy with a nano-Cu-rich structure according to claim 3, characterized in that, The melting temperature in step 3 is 1700~2100 ℃. After flipping, it is remelted twice, and the melting time for each melting is not less than 60 s.

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