A modified titanium alloy material, a preparation method and application thereof

Abstract

This invention provides a modified titanium alloy material, its preparation method, and its applications, including an antibacterial coating formed on the surface of a titanium alloy after nitriding treatment for use in medical materials. The antibacterial coating includes nickel-containing nitrides. The modified titanium alloy prepared by the technical solution of this invention exhibits good antibacterial properties and excellent biocompatibility.

Description

Technical Field

[0001] This invention relates to the field of medical biomaterial preparation technology, and more specifically, to the preparation and application of an antibacterial coating for the surface of medical titanium alloy materials. Background Technology

[0002] With the increasing aging of my country's population and the rising demand for higher-quality medical services, the implantable medical device market is showing tremendous growth potential. Titanium alloys, with their excellent mechanical properties, wear resistance, and corrosion resistance, are widely used in the manufacture of clinical dental and orthopedic implant materials.

[0003] However, the bioinertness of titanium alloy surfaces means that bacterial colonization can easily lead to implant failure, and replacing a failed implant significantly increases surgical costs. The conventional treatment for bacterial infections is antibiotic therapy, but overuse of antibiotics can accelerate the development of drug-resistant bacteria. When a bacterial infection develops into a biofilm infection, the biofilm matrix can resist antibiotic penetration, greatly reducing antibiotic sensitivity. Even high doses of antibiotics may not be enough to eradicate the biofilm infection. Bacterial infections of titanium alloy implants not only increase medical costs but also threaten patients' lives.

[0004] Therefore, it is necessary to modify the originally surface-inert titanium alloy material to make its surface bioactive without losing the excellent mechanical properties of the main body of the material, and to enable it to exert efficient, stable and broad-spectrum antibacterial functions. This is of great value for the upgrading of clinical products and the progress of society.

[0005] Plasma immersion ion implantation and deposition (PIII&D) is a mature material surface modification technology widely used in semiconductor chip manufacturing and biomaterial surface modification. Both solids and gases can generate plasma; arc ionization can generate solid target plasma, and radio frequency glow discharge can generate gaseous plasma. The workpiece is connected to a pulsed negative high-voltage voltage. Under the influence of the sheath electric field, the workpiece immersed in plasma is bombarded by plasma from the sheath in a direction perpendicular to the workpiece surface. The implanted ions are diffusely distributed on the surface, ultimately producing a uniform modified workpiece without obvious interfaces. PIII&D offers unique advantages for biomaterial surface modification. Its comprehensive modification capabilities allow it to adapt to intricately designed implantable devices, and the near-room temperature modification environment does not excessively affect the main properties of the workpiece material. Summary of the Invention

[0006] In view of the problems in the prior art, the purpose of this invention is to provide a modified titanium alloy material, its preparation method and application.

[0007] On one hand, the present invention provides a modified titanium alloy material, including a titanium alloy and an antibacterial coating formed on its surface, wherein the antibacterial coating includes nickel-containing nitrides.

[0008] Preferably, the nickel-containing nitride is formed by active nickel nitriding treatment on the surface of a titanium alloy.

[0009] Preferably, the active nickel is formed by plasma immersion injection technology.

[0010] Preferably, the nitriding treatment is performed using plasma immersion injection technology.

[0011] On the other hand, the present invention provides a method for preparing a modified titanium alloy material, comprising the following steps:

[0012] Step 1: Construct active nickel on the surface of the titanium alloy;

[0013] Step 2: The surface of the titanium alloy is subjected to active nickel nitriding treatment to form an antibacterial coating containing nickel nitrides.

[0014] Preferably, the titanium alloy contains nickel, and in step 1, high-energy metal plasma or gas plasma is injected using plasma immersion injection technology to expose the active nickel in the titanium alloy.

[0015] Preferably, the titanium alloy does not contain nickel, and active nickel is injected in step 1 using plasma immersion injection technology.

[0016] Preferably, the nickel loading in the antibacterial coating of step 2 is less than 20 at.%.

[0017] Preferably, the nitrogen loading in the antibacterial coating of step 2 is less than 20 at.%.

[0018] On the other hand, the present invention provides an application of modified titanium alloy material in antibacterial medical materials.

[0019] The nickel-containing nitride coating formed on the surface of the modified titanium alloy sample according to the technical solution of the present invention has significant antibacterial properties against Staphylococcus aureus and Escherichia coli. At the same time, cells can grow and proliferate normally on the material surface without showing cytotoxicity. Attached Figure Description

[0020] Other features, objects, and advantages of the invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings.

[0021] Figure 1The images are scanning electron microscope (SEM) images of the materials, where NiTi represents the unmodified sample, NiTi-N represents the sample with a single nitrogen ion implantation, NiTi-Ar represents the sample with a single argon ion implantation, NiTi-Ar-N represents the sample with argon implantation followed by nitrogen implantation, NiTi-Co represents the sample with a single cobalt ion implantation, NiTi-Co-N represents the sample with cobalt implantation followed by nitrogen implantation, NiTi-Zr represents the sample with a single zirconium ion implantation, and NiTi-Zr-N represents the sample with zirconium implantation followed by nitrogen implantation.

[0022] Figure 2 The image shows the total XPS spectrum of the material surface (the horizontal axis represents the binding energy), where NiTi represents the unmodified sample, NiTi-N represents the sample with a single nitrogen ion implantation, NiTi-Ar represents the sample with a single argon ion implantation, NiTi-Ar-N represents the sample with argon implantation followed by nitrogen implantation, and NiTi-Zr-N represents the sample with zirconium implantation followed by nitrogen implantation.

[0023] Figure 3 Ni2p (for XPS on the material surface) Figure 3 a) N1s ( Figure 3 b) High-resolution spectrum (the horizontal axis represents binding energy), where NiTi represents the unmodified sample, NiTi-N represents the sample with a single nitrogen ion implantation, NiTi-Ar represents the sample with a single argon ion implantation, NiTi-Ar-N represents the sample with argon implantation followed by nitrogen implantation, and NiTi-Zr-N represents the sample with zirconium implantation followed by nitrogen implantation.

[0024] Figure 4 For the electrochemical characterization of materials, Figure 4 In the figure, 'a' represents the Tafel curve (the horizontal axis represents current density, and the vertical axis represents electric potential). Figure 4 b is the EIS Nyquist plot. Figure 4 In the middle, c represents the Bode plot (the horizontal axis is frequency, and the vertical axis is impedance). Figure 4 In the diagram, d represents the phase angle (the horizontal axis is frequency, and the vertical axis is phase angle). Figure 4 In the figure, e represents the calculated corrosion potential and corrosion current, where NiTi represents the unmodified sample, NiTi-N represents the sample with only nitrogen ion implantation, NiTi-Ar represents the sample with only argon ion implantation, and NiTi-Ar-N represents the sample with argon implantation followed by nitrogen implantation.

[0025] Figures 5a-5dThe results of plate experiments on the surface of metal- and nitrogen-impregnated samples for Escherichia coli and Staphylococcus aureus (E. coli represents Escherichia coli, S. aureus represents Staphylococcus aureus). Among them, NiTi represents unmodified samples, NiTi-N represents samples with only nitrogen ion implantation, NiTi-Co represents samples with only cobalt ion implantation, NiTi-Co-N represents samples with cobalt implantation followed by nitrogen implantation, NiTi-Zr represents samples with only zirconium ion implantation, NiTi-Zr-N represents samples with zirconium implantation followed by nitrogen implantation, NiTi-Ce represents samples with only zirconium ion implantation, and NiTi-Ce-N represents samples with zirconium implantation followed by nitrogen implantation.

[0026] Figure 6 The results of the plate coating experiment on the surface of argon- and nitrogen-injected samples for Escherichia coli and Staphylococcus aureus (E. coli represents Escherichia coli, S. aureus represents Staphylococcus aureus), where NiTi represents unmodified samples, NiTi-N represents samples with only nitrogen ion injection, NiTi-Ar represents samples with only argon ion injection, and NiTi-Ar-N represents samples with argon injection followed by nitrogen injection.

[0027] Figure 7 The results of plate experiments on the surface of hydrogen- and nitrogen-injected samples for Escherichia coli and Staphylococcus aureus (E. coli represents Escherichia coli, S. aureus represents Staphylococcus aureus), where NiTi represents unmodified samples, NiTi-N represents samples with only nitrogen ion injection, NiTi-H represents samples with only argon ion injection, and NiTi-HN represents samples with argon injection followed by nitrogen injection.

[0028] Figure 8 The results of plate experiments on the surface of oxygen- and nitrogen-injected samples for Escherichia coli and Staphylococcus aureus (E. coli represents Escherichia coli, S. aureus represents Staphylococcus aureus), where NiTi represents unmodified samples, NiTi-N represents samples with only nitrogen ion injection, NiTi-O represents samples with only argon ion injection, and NiTi-ON represents samples with argon injection followed by nitrogen injection.

[0029] Figure 9 Scanning electron micrographs of Escherichia coli and Staphylococcus aureus on the surface of argon-injected and nitrogen-injected samples (E. coli represents Escherichia coli, S. aureus represents Staphylococcus aureus). NiTi represents unmodified samples, NiTi-N represents samples with single nitrogen ion injection, NiTi-Ar represents samples with single argon ion injection, NiTi-Ar-N represents samples with argon injection followed by nitrogen injection, NiTi-Zr represents samples with single zirconium ion injection, and NiTi-Zr-N represents samples with zirconium injection followed by nitrogen injection.

[0030] Figure 10The surface inhibition zone experiment of NiTi-Ar-N samples (E. coli represents Escherichia coli, S. aureus represents Staphylococcus aureus), where NiTi represents unmodified samples, NiTi-N represents samples with single nitrogen ion implantation, NiTi-Ar represents samples with single argon ion implantation, and NiTi-Ar-N represents samples with argon implantation followed by nitrogen implantation.

[0031] Figure 11 Images show the results of plate experiments on the surface of heat-treated samples containing Escherichia coli and Staphylococcus aureus. NiTi represents unmodified samples, NiTi-N represents samples with single nitrogen ion implantation, NiTi-Ar represents samples with single argon ion implantation, NiTi-Ar-N represents samples with argon implantation followed by nitrogen implantation, and NiTi-Zr-N represents samples with zirconium implantation followed by nitrogen implantation.

[0032] Figure 12 Images of plate experiments showing the results of multiple inoculations of Staphylococcus aureus onto the surface of NiTi-Ar-N samples; where NiTi represents the unmodified sample, NiTi-Ar-N represents the sample injected with argon and then nitrogen, and the serial number indicates the number of times bacteria were inoculated;

[0033] Figure 13 Images showing the antibacterial effects of nickel and nitrogen implantation on Staphylococcus aureus on the surface of titanium-zirconium alloys; where TiZr represents the unmodified sample, TiZr-N represents the sample with only nitrogen ion implantation, TiZr-Ni represents the sample with only nickel ion implantation, and TiZr-Ni-N represents the sample with nickel implantation followed by nitrogen implantation.

[0034] Figure 14 Images show the experimental results of gallbladder epithelial cell proliferation on the surface of argon- and nitrogen-injected samples. NiTi represents the unmodified sample, NiTi-N represents the sample with nitrogen ion injection alone, NiTi-Ar represents the sample with argon ion injection alone, and NiTi-Ar-N represents the sample with argon injection followed by nitrogen injection.

[0035] Figure 15 Images show the experimental results of human umbilical vein endothelial cells proliferating on the surface of argon- and nitrogen-injected samples. NiTi represents unmodified samples, NiTi-N represents samples injected with nitrogen ions alone, NiTi-Ar represents samples injected with argon ions alone, and NiTi-Ar-N represents samples injected with argon followed by nitrogen. Detailed Implementation

[0036] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that the invention will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore repeated descriptions of them will be omitted.

[0037] This invention provides a modified titanium alloy material, including a titanium alloy and an antibacterial coating formed on its surface, wherein the antibacterial coating includes nickel-containing nitrides.

[0038] Preferably, the nickel-containing nitride is formed by active nickel nitriding treatment on the surface of the titanium alloy. The active nickel is formed using plasma immersion implantation technology. The nitriding treatment is performed using plasma immersion implantation technology.

[0039] The modified titanium alloy material of this invention comprises a metal nitride modified coating formed on the surface of the titanium alloy material. The metal exists in the form of element, oxide, and nitride; the nitrogen exists in the form of metal nitrides such as nickel nitride and titanium nitride. Preferably, the nickel loading of the surface coating is less than 20 at.%; the nitrogen loading of the surface coating is less than 20 at.%.

[0040] Furthermore, this invention also provides a method for preparing a modified titanium alloy material, comprising the following steps:

[0041] Step 1: Construct an active nickel coating on the titanium alloy surface. The nickel in the active nickel coating is active in undergoing a nitriding reaction. Preferably, the nickel in the active nickel coating can comprise elemental nickel or nickel oxide. The construction method includes:

[0042] Destroying the passivation film on the surface of the nickel-containing substrate exposes the active nickel. For nickel-containing titanium alloys, preferably nickel-titanium alloys, an active nickel coating can be constructed by injecting metallic plasma (cobalt, zirconium, cerium, titanium, etc.) or gaseous plasma (argon plasma, hydrogen plasma) onto the titanium alloy surface to destroy the passivation film on the nickel-containing substrate and expose the active nickel. It is worth noting that injecting oxygen plasma cannot destroy the surface passivation film and expose the active nickel.

[0043] An active nickel coating can be constructed on the surface of a nickel-free substrate material using surface modification techniques. For nickel-free titanium alloys, an active nickel coating can be constructed by implanting nickel into the titanium alloy surface.

[0044] Preferably, the cathode target used for metal implantation is an elemental metal.

[0045] Preferably, when injecting metals (cobalt, zirconium, cerium, titanium, nickel, etc.), the PIII&D process parameters include: vacuum chamber temperature of 20–40°C; and a background vacuum of 5 × 10⁻⁶. -3 Pa; negative high voltage is -15 to -40 kV; frequency is 5 to 10 Hz; pulse width is 500 to 1000 μs; injection time is 60 to 120 min.

[0046] The preferred percentage of metal atoms implanted on the material surface is 0–15 at.%.

[0047] The preferred cathode target for gas injection is mainly composed of elemental gas.

[0048] Preferably, the PIII&D process parameters used during gas injection include: vacuum chamber temperature of 20–100°C; and a background vacuum of 5 × 10⁻⁶. -3 Pa; negative high voltage of -15 to -40 kV; frequency of 5 to 150 Hz; pulse width of 50 μs; injection time of 1 to 2 h; gas flow rate of 10 to 50 cm³ / h. 3 / min.

[0049] Step 2: The surface of the titanium alloy is subjected to active nickel nitriding treatment to form an antibacterial coating containing nickel nitrides.

[0050] Nitriding treatment involves synthesizing nickel-containing nitrides on the surface.

[0051] Plasma immersion injection technology is preferred for plasma nitriding treatment of titanium alloy surfaces.

[0052] The optimal nitrogen injection process parameters are: a background vacuum of less than 5 × 10⁻⁶. -3 Pa, injection voltage of 10-50kV, negative high voltage pulse width of 10-100μs, negative high voltage frequency of 5-150Hz, and injection time of more than 30 minutes.

[0053] In addition, metal plasma injection preferably uses pure metal with a purity greater than 99.9% as the cathode target; gas injection uses elemental gas with a purity greater than 99.9% to provide the required plasma; that is, argon provides argon plasma, hydrogen provides hydrogen plasma, and nitrogen provides nitrogen plasma.

[0054] The percentage of nitrogen atoms implanted on the material surface is 0–15 at.%.

[0055] The method further includes a step of treating and washing the substrate with an acid pickling solution before plasma immersion ion implantation. Preferably, the acid pickling solution is a mixture of nitric acid and hydrofluoric acid; additionally preferably, the washing step involves ultrasonic cleaning with acetone, ethanol, and deionized water in sequence.

[0056] In addition, embodiments of the present invention also provide the application of surface-modified titanium alloy materials in the biomedical field, especially in antibacterial applications.

[0057] The nickel-containing nitride coating formed on the surface of the modified titanium alloy sample in this invention exhibits good antibacterial properties and excellent biocompatibility. It demonstrates significant antibacterial activity against Staphylococcus aureus and Escherichia coli. Cell proliferation experiments show that cells can grow and proliferate normally on the material surface, without exhibiting cytotoxicity. The application of this coating material...

[0058] The present invention will now be described with reference to specific embodiments and comparative examples:

[0059] Among them, the titanium alloy uses nickel-titanium or titanium-zirconium alloy as the substrate, the metal injection uses pure metal as the cathode, and the gas injection uses radio frequency excitation gas to provide plasma.

[0060] Metal implantation was performed using the following process parameters: background vacuum level of 5 × 10⁻⁶. -3 Pa; negative high voltage is -15 to -40 kV, pulse width is 500 to 1000 μs, frequency is 5 to 10 Hz, and injection time is 1 to 3 hours.

[0061] Argon, hydrogen, and oxygen plasma immersion ion implantation is performed using the following process parameters: background vacuum of 5 × 10⁻⁶. -3 Pa, injection voltage -15kV, pulse width 50μs, frequency 100Hz, injection time 2 hours.

[0062] The nitrogen plasma immersion ion implantation method is carried out using the following process parameters: background vacuum level is 5 × 10⁻⁶. -3 Pa; negative high voltage is -30kV, pulse width is 50μs, frequency is 100Hz, and injection time is 1 hour.

[0063] The experimental procedure is described in detail below:

[0064] 1. A nickel-titanium sheet with a diameter of 12 mm and a thickness of 1 mm is ultrasonically treated twice with a mixed acid (hydrofluoric acid: nitric acid: deionized water = 1:5:4) (5 minutes each time), and then ultrasonically cleaned twice with deionized water and ethanol for 5 minutes each time, to obtain a nickel-titanium alloy sheet with a smooth surface. The resulting material is named NiTi. A titanium-zirconium sheet with a diameter of 8 mm and a thickness of 1 mm is ultrasonically treated twice with a mixed acid (hydrofluoric acid: nitric acid: deionized water = 1:5:34) (5 minutes each time), and then ultrasonically cleaned twice with deionized water and ethanol for 5 minutes each time, to obtain a titanium-zirconium alloy sheet with a smooth surface. The resulting material is named TiZr.

[0065] 2. Using plasma immersion injection and deposition technology, metals were injected into nickel-titanium substrates and named NiTi-Co, NiTi-Zr, NiTi-Ti, and NiTi-Ce, respectively; nickel was injected into titanium-zirconium substrates and named TiZr-Ni. Specific parameters are shown in Table 1.

[0066] Table 1: Metal ion implantation and deposition parameters

[0067]

[0068] 3. Using plasma immersion injection and deposition technology, argon / hydrogen / oxygen / nitrogen are injected into the nickel-titanium matrix. The specific process parameters are shown in Table 2 and named NiTi-Ar, NiTi-H, NiTi-O, NiTi-N, and TiZr-N, respectively.

[0069] Table 2: Gas ion implantation and deposition parameters

[0070]

[0071] 4. Using plasma immersion injection and deposition technology, according to the above parameters, the first step is to inject metal or gas, and the second step is to inject nitrogen. The resulting samples are named NiTi-Co-N, NiTi-Zr-N, NiTi-Ti-N, NiTi-Ce-N, NiTi-Ar-N, NiTi-HN, NiTi-ON, and TiZr-Ni-N, respectively.

[0072] 5. Evaluation of the surface physicochemical properties of the material.

[0073] like Figure 1 As shown, at a magnification of 20,000x, no significant changes in the morphology of the sample were observed after ion implantation, and there were a few traces of mechanical processing residue on the sample surface.

[0074] As shown in Table 3, the nickel content on the surface of NiTi, NiTi-N, NiTi-Ar, NiTi-Ar-N, and NiTi-Zr-N samples remained at a low level, suggesting good biocompatibility of the materials.

[0075] Table 3: Elemental content of sample surface layer as measured by XPS

[0076] sample C1s(at.%) O1s(at.%) Ni2p (at.%) Ti2p(at.%) N1s(at.%) Zr3d(at.%) NiTi 34.45 42.27 2.37 20.91 - - NiTi-N 32.6 44.31 1.6 17.3 4.19 - NiTi-Ar 40.71 42.56 1.84 14.9 - - NiTi-Ar-N 34.59 43.31 2.34 15.58 4.19 - NiTi-Zr-N 33.62 42.48 0.96 6.3 4.9 11.74

[0077] like Figure 2 As shown, the corresponding elements can be found in the overall spectrum of both metal and gas samples after ion implantation.

[0078] like Figure 3As shown, the peak positions of elemental nickel and divalent nickel in NiTi-Zr-N and NiTi-Ar-N samples are shifted to the peak positions of monovalent nickel. The high-resolution spectrum of nitrogen shows that NiTi-Zr-N and NiTi-Ar-N samples have obvious Ni-N and Ti-N peaks, and nickel nitride and titanium nitride are formed on the surface.

[0079] like Figure 4 As shown, NiTi-N exhibits improved corrosion resistance due to the protection of the surface titanium nitride layer, while NiTi-Ar is more susceptible to corrosion due to the destruction of the surface oxide layer. The corrosion current of the NiTi-Ar-N sample falls between the two, and its corrosion resistance is close to that of the NiTi sample.

[0080] 6. Evaluation of the antibacterial properties of the material.

[0081] The material was immersed in a 75% ethanol solution and placed on a shaker, with the solution changed every 30 minutes. After sterilization for 2 hours, it was air-dried for later use. (The last sentence appears to be incomplete and possibly refers to a separate topic: "In Escherichia coli (E. coli, ATCC...") In experiments with *Staphylococcus aureus* (ATCC 25922) and *Staphylococcus aureus* (ATCC 25923), the bacterial solution was adjusted to an absorbance of 0.1 at 600 nm using culture medium. It was then diluted tenfold with TSB medium and then tenfold with physiological saline, resulting in a bacterial density of approximately 10⁶ CFU / mL. The antibacterial properties of the material were characterized using the bacterial plate coating method. Bacteria were inoculated onto the material surface at a concentration of 0.06 mL / cm² and cultured at 37°C for 24 h. After culturing, the bacterial solution was diluted to a suitable concentration and plated onto solid TSB agar medium. After culturing at 37°C for 16-18 h, the plate was photographed. To observe the microscopic morphology of the bacteria on the material surface, the bacteria were inoculated onto the material surface and cultured at 37°C for 24 h. The bacterial morphology was then fixed with 2.5% glutaraldehyde at 4°C. After gradient dehydration (30 v% ethanol, 50 v% ethanol, 75 v% ethanol, 90 v% ethanol, 95 v% ethanol, 100 v% ethanol), the bacterial morphology was observed using a scanning electron microscope.

[0082] like Figures 5a-5d As shown in the bacterial plate coating results, it can be found that simply injecting metal under the above experimental parameters cannot make the material antibacterial. However, the modified titanium alloys that were first injected with metal and then with nitrogen all showed a bactericidal rate of more than 99% against Escherichia coli and Staphylococcus aureus.

[0083] like Figure 6 As shown in the bacterial plate coating results, it can be found that simply injecting argon gas under the above experimental parameters cannot make the material antibacterial. However, the NiTi-Ar-N sample showed a bactericidal rate of more than 99% against Escherichia coli and Staphylococcus aureus.

[0084] like Figure 7As shown in the bacterial plate coating results, it can be found that simply injecting hydrogen gas under the above experimental parameters cannot make the material antibacterial. However, the NiTi-HN sample showed a bactericidal rate of more than 99% against Staphylococcus aureus, but did not show obvious antibacterial activity against Escherichia coli. This may be because the hydrogen injection did not completely destroy the surface passivation film, but only partially exposed the nickel active sites, resulting in less nickel nitride formation, thus selectively killing Staphylococcus aureus.

[0085] like Figure 8 As shown in the bacterial plate coating results, the NiTi-ON samples did not exhibit resistance to Escherichia coli and Staphylococcus aureus under the above experimental parameters.

[0086] like Figure 9 As shown, the surfaces of NiTi, NiTi-N, and NiTi-Ar samples were covered with a large number of Escherichia coli and Staphylococcus aureus, and the bacteria were saturated. However, the number of Escherichia coli and Staphylococcus aureus on the surface of NiTi-Ar-N sample was much smaller than that of the other groups, and obvious bacterial membrane shrinkage and rupture were observed, which further illustrates the bactericidal effect of NiTi-Ar-N sample.

[0087] like Figure 10 As shown, no inhibition zone was found around the NiTi, NiTi-N, NiTi-Ar, and NiTi-Ar-N samples, indicating that the released ions were insufficient to kill the surrounding bacteria.

[0088] like Figure 11 As shown, nickel nitride is temperature sensitive. After heat treatment at 500℃ for 2 hours, the originally antibacterial NiTi-Ar-N and NiTi-Zr-N samples lost their antibacterial properties, further illustrating the important role of nickel nitride in antibacterial activity.

[0089] like Figure 12 As shown, repeated inoculation of Staphylococcus aureus on the same sample surface revealed that NiTi-Ar-N can exert a long-lasting and stable antibacterial effect, showing promising application prospects.

[0090] like Figure 13 As shown, it can be seen that TiZr implanted with nickel for 1 hour does not exhibit antibacterial properties, but TiZr-Ni-N can kill bacteria on the surface.

[0091] 7. Evaluation of the biocompatibility of the materials.

[0092] The material was immersed in a 75% ethanol solution and shaken on a shaker, with the solution changed every 30 minutes. After sterilization for 2 hours, it was air-dried for later use. To evaluate the cell proliferation behavior on the material surface, gallbladder epithelial cells (HGBECs) and human umbilical vein endothelial cells (HUVECs) were seeded at a cell density of 20,000 cells / well. The fluorescence intensity at 1, 4, and 7 days was measured using the Alamar Blue assay to reflect cell proliferation activity, and the biocompatibility of the modified material was characterized from the cell proliferation activity.

[0093] like Figure 14 As shown, the proliferation activity of gallbladder epithelial cells on the NiTi-Ar-N surface was significantly improved compared with the blank nickel-titanium group, which fully demonstrates the excellent biocompatibility of NiTi-Ar-N.

[0094] like Figure 15 As shown, the proliferation activity of human umbilical vein endothelial cells on the NiTi-Ar-N surface was basically the same as that of the blank nickel-titanium group, which also demonstrates the excellent biocompatibility of NiTi-Ar-N.

[0095] In summary, the method of this invention is stable and controllable, simple to operate, and can modify workpieces in all directions without being limited by shape. The modified titanium alloy prepared has good antibacterial properties and excellent biocompatibility.

[0096] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A modified titanium alloy material, characterized by, This includes titanium alloys and antibacterial coatings formed on their surfaces, the antibacterial coatings comprising nickel-containing nitrides. The titanium alloy contains nickel, and the preparation method of the modified titanium alloy material includes the following steps: Step 1: High-energy metal plasma or gas plasma is injected using plasma immersion injection technology to expose the active nickel in the titanium alloy, thereby constructing active nickel on the surface of the titanium alloy. Step 2: The surface of the titanium alloy is subjected to active nickel nitriding treatment to form an antibacterial coating containing nickel nitrides. The nickel loading in the antibacterial coating is less than 20 at.%, and the nitrogen loading in the antibacterial coating is less than 20 at.%.

2. A modified titanium alloy material, characterized in that, This includes titanium alloys and antibacterial coatings formed on their surfaces, the antibacterial coatings comprising nickel-containing nitrides. The titanium alloy does not contain nickel, and the preparation method of the modified titanium alloy material includes the following steps: Step 1: Active nickel is injected onto the surface of the titanium alloy using plasma immersion implantation technology to construct active nickel. Step 2: The surface of the titanium alloy is subjected to active nickel nitriding treatment to form an antibacterial coating containing nickel nitrides. The nickel loading in the antibacterial coating is less than 20 at.%, and the nitrogen loading in the antibacterial coating is less than 20 at.%.

3. The modified titanium alloy material according to claim 1 or 2, characterized in that: The nitriding treatment is performed using plasma immersion injection technology.

4. The application of the modified titanium alloy material according to claim 1 in antibacterial medical materials.

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