Antibacterial titanium alloy and preparation method thereof

Abstract

The invention belongs to the technical field of metal surface treatment, and discloses an antibacterial titanium alloy and a preparation method thereof. The method comprises the following steps: S1, carrying out chemical degreasing, primary washing, pickling activation and secondary washing on a titanium alloy base material; s2, the pretreated titanium alloy base material is subjected to anodic oxidation to prepare an antibacterial oxidation film; and S3, sealing treatment and curing treatment are conducted on the antibacterial oxidation film. Antibacterial substances are added into the anodic oxidation liquid, silver ion doped porous nano titanium dioxide is added into the sealing treatment liquid, and the titanium alloy has good and lasting antibacterial performance through two times of antibacterial treatment of anodic oxidation and sealing treatment. And a layer of compact oxidation film without antibacterial substances is formed on the surface of the titanium alloy through pre-anodic oxidation, so that the situation that silver ions and titanium dioxide particles permeate into a titanium alloy interface in the subsequent anodic oxidation step and are enriched at the interface to cause interface embrittlement and hardness reduction is effectively prevented, and the interface bonding force is improved.

Description

Technical Field

[0001] This invention belongs to the field of metal surface treatment technology, specifically relating to an antibacterial titanium alloy and its preparation method. Background Technology

[0002] With rising public health standards, there is an urgent need for antibacterial metal materials in the medical, food, and public facilities sectors.

[0003] Currently, common methods for achieving antibacterial properties in titanium alloys mainly fall into two categories: surface coating and antibacterial alloying. However, existing technologies face several challenges: surface coatings suffer from weak adhesion to the substrate, making them prone to wear and detachment, thus rendering their antibacterial function unreliable. While alloying can achieve bulk antibacterial properties, sufficient antibacterial elements must be added to ensure effectiveness, which can easily lead to the precipitation of brittle phases. Therefore, providing a titanium alloy that maintains antibacterial properties while possessing excellent overall performance has significant social and economic value. Summary of the Invention

[0004] In view of the above-mentioned problems in the existing technology, the purpose of this invention is to provide an antibacterial titanium alloy and its preparation method.

[0005] To address the above problems, the present invention provides the following technical solution: In a first aspect, this application provides a method for preparing an antibacterial titanium alloy, comprising the following steps: S1. Chemical degreasing, primary water washing, acid pickling activation, and secondary water washing are performed on the titanium alloy substrate. S2. Anodize the pretreated titanium alloy substrate to prepare an antibacterial oxide film. S3. The antibacterial oxide film is sealed and cured.

[0006] In one embodiment of this application, in step S1, chemical degreasing involves immersing the titanium alloy in a chemical degreasing solution for 5-10 minutes.

[0007] In one embodiment of this application, in step S1, the chemical degreasing solution includes 10-30 g / L sodium hydroxide, 20-30 g / L sodium carbonate, 30-50 g / L trisodium phosphate, 5-10 g / L sodium silicate, 1-3 ml / L octylphenol polyoxyethylene ether-10, and the balance being deionized water.

[0008] In one embodiment of this application, in step S1, the temperature of the chemical degreasing solution is 60-80°C.

[0009] In one embodiment of this application, in step S1, the pickling activation involves immersing the titanium alloy in the pickling activation solution for 0.5-10 minutes.

[0010] In one embodiment of this application, in step S1, the pickling activation solution includes 15-30 vol% nitric acid, 1-5 vol% hydrofluoric acid, and the remainder being deionized water.

[0011] In one embodiment of this application, in step S1, the temperature of the pickling activation solution is 20-25°C.

[0012] In one embodiment of this application, after step S1 and before step S2, a pre-anodizing treatment of the titanium alloy is further included.

[0013] In one embodiment of this application, pre-anodization is performed using a titanium alloy as the anode and a stainless steel plate or lead plate as the cathode under constant voltage conditions.

[0014] In one embodiment of this application, the pre-anodized liquid is a 160-180 g / L sulfuric acid solution.

[0015] In one embodiment of this application, the pre-anodizing parameters are a voltage of 1-30V, a time of 1-5min, and a temperature of 20-30℃.

[0016] In one embodiment of this application, the pre-anodization time is 2-3 minutes.

[0017] In one embodiment of this application, a dense pre-oxidized film without antibacterial substances is formed on the surface of a titanium alloy by pre-anodization.

[0018] In one embodiment of this application, the thickness of the dense pre-oxidized layer is 20-30 nm.

[0019] In one embodiment of this application, in step S2, anodizing is performed using a titanium alloy as the anode and a stainless steel plate or lead plate as the cathode under constant voltage conditions.

[0020] In one embodiment of this application, in step S2, the liquid used for anodizing is 160-220 g / L sulfuric acid, 1-5 g / L antibacterial substance, and the remainder being deionized water.

[0021] In one embodiment of this application, in step S2, the antibacterial substance is silver nitrate and silver ion-doped porous titanium dioxide.

[0022] In one embodiment of this application, in step S2, the ratio of silver nitrate to silver ion-doped porous titanium dioxide is 1-3:1-2.

[0023] In one embodiment of this application, in step S2, the pore size of the silver ion-doped porous titanium dioxide is 10-50 nm, and the Ag loading is 1-3 wt.%.

[0024] In one embodiment of this application, in step S2, the parameters for anodizing are: voltage of 1-100V, anodizing time of 1-10min, and anodizing temperature of 20-30℃.

[0025] In one embodiment of this application, in step S2, an anodized layer containing antibacterial substances is generated by anodizing.

[0026] In one embodiment of this application, in step S2, the thickness of the dense pre-oxidized layer and the anodic oxide layer containing antibacterial substances is 25-50 nm.

[0027] In one embodiment of this application, in step S3, the solution for the sealing treatment consists of 50-70 wt.% alcohol, 30-40 wt.% dispersant, and 1-5 wt.% silver ion-doped porous nano-titanium dioxide.

[0028] In one embodiment of this application, the sealing process in step S3 takes 3-10 minutes.

[0029] In one embodiment of this application, the temperature of the sealing process in step S3 is 20-25°C.

[0030] In one embodiment of this application, in step S3, the alcohol is selected from at least one of sorbitol, glycerol, propylene glycol, isopropanol, and polyethylene glycol.

[0031] In one embodiment of this application, in step S3, the dispersant is selected from at least one of sodium methylene bis(naphthalene) sulfonate, sodium methylene bis(naphthalene) sulfonate, nanocellulose, sodium cellulose sulfonate, and sodium dodecylbenzene sulfonate.

[0032] In one embodiment of this application, in step S3, the curing temperature is 100-150°C.

[0033] In one embodiment of this application, the curing time in step S3 is 30-60 minutes.

[0034] Secondly, this application provides an antibacterial titanium alloy prepared by the above-described preparation method.

[0035] Compared with the prior art, the present invention has the following beneficial effects: (1) The anodic oxidation solution of this application contains antibacterial substances, and the sealing treatment solution contains silver ion-doped porous nano titanium dioxide. Through two antibacterial treatments of anodic oxidation and sealing treatment, the titanium alloy has good and long-lasting antibacterial properties.

[0036] (2) This application forms a dense oxide film without antibacterial substances on the surface of titanium alloy by pre-anodization, which effectively prevents silver ions and titanium dioxide particles in the subsequent anodizing step from penetrating into the titanium alloy interface, accumulating at the interface and causing interface embrittlement and hardness reduction, thereby improving the interface bonding force.

[0037] (3) The preparation method of this application is simple and does not require an additional new and independent anodizing process, which is convenient for large-scale production. Detailed Implementation

[0038] The technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0039] Unless otherwise specified, all materials and reagents used in the following examples are commercially available. Example 1

[0040] This embodiment provides a method for preparing an antibacterial titanium alloy: A chemical degreasing solution was prepared using 20 g / L sodium hydroxide, 25 g / L sodium carbonate, 40 g / L trisodium phosphate, 7.5 g / L sodium silicate, 2 ml / L octylphenol polyoxyethylene ether-10, and deionized water. The temperature of the chemical degreasing solution was maintained at 70°C. The aluminum alloy was immersed in the chemical degreasing solution for 7.5 minutes. It was then rinsed with deionized water at room temperature for 1 minute.

[0041] A pickling activation solution was prepared using 20 vol% nitric acid, 3 vol% hydrofluoric acid, and deionized water. The degreased aluminum alloy was immersed in the pickling activation solution at room temperature for 3 minutes. It was then rinsed with deionized water at room temperature for 1 minute.

[0042] Pre-anodization was performed in a 170 g / L sulfuric acid solution under the following conditions: titanium alloy as the anode, stainless steel plate as the cathode, constant voltage mode, voltage 15 V, temperature 20 °C, for 2.5 min. The mixture was then rinsed with deionized water at room temperature for 1 min.

[0043] An anodizing solution was prepared using 180 g / L sulfuric acid, 3 g / L antibacterial material (silver nitrate: silver ion-doped porous nano-titanium dioxide = 2:1, wherein the pore size of the silver ion-doped porous titanium dioxide is 10-50 nm and the Ag loading is 2 wt.%), and deionized water. A titanium alloy was used as the anode, and a stainless steel plate as the cathode. A constant voltage mode was employed: 16 V, 20 °C, and anodizing for 10 min. The mixture was then rinsed with deionized water at room temperature for 1 min and dried at 80 °C for 10 min.

[0044] A sealing solution was prepared using 60% isopropanol, 32% sodium methylene bis(naphthalene) sulfonate, and 5% silver ion-doped porous nano-titanium dioxide, and the solution was sealed at 20°C for 5 min.

[0045] Cur at 120℃ for 45 minutes. Example 2

[0046] This embodiment provides a method for preparing an antibacterial titanium alloy: A chemical degreasing solution was prepared using 20 g / L sodium hydroxide, 25 g / L sodium carbonate, 40 g / L trisodium phosphate, 7.5 g / L sodium silicate, 2 ml / L octylphenol polyoxyethylene ether-10, and deionized water. The temperature of the chemical degreasing solution was maintained at 70°C. The aluminum alloy was immersed in the chemical degreasing solution for 7.5 minutes. It was then rinsed with deionized water at room temperature for 1 minute.

[0047] A pickling activation solution was prepared using 20 vol% nitric acid, 3 vol% hydrofluoric acid, and deionized water. The degreased aluminum alloy was immersed in the pickling activation solution at room temperature for 3 minutes. It was then rinsed with deionized water at room temperature for 1 minute.

[0048] Pre-anodization was performed in a 170 g / L sulfuric acid solution under the following conditions: titanium alloy as the anode, stainless steel plate as the cathode, constant voltage mode, voltage 15 V, temperature 20 °C, for 2.5 min. The mixture was then rinsed with deionized water at room temperature for 1 min.

[0049] An anodizing solution was prepared using 180 g / L sulfuric acid, 3 g / L antibacterial material (silver nitrate: silver ion-doped porous nano-titanium dioxide = 2:1, wherein the pore size of the silver ion-doped porous titanium dioxide is 10-50 nm and the Ag loading is 2 wt.%), and deionized water. A titanium alloy was used as the anode, and a stainless steel plate as the cathode. A constant voltage mode was employed: 16 V, 20 °C, and anodizing for 10 min. The mixture was then rinsed with deionized water at room temperature for 1 min and dried at 80 °C for 10 min.

[0050] A sealing solution was prepared using 60% polyethylene glycol, 35% nanocellulose, and 5% silver ion-doped porous nano-titanium dioxide, and sealed at 20°C for 5 minutes.

[0051] Cur at 120℃ for 45 minutes. Example 3

[0052] This embodiment provides a method for preparing an antibacterial titanium alloy: A chemical degreasing solution was prepared using 20 g / L sodium hydroxide, 25 g / L sodium carbonate, 40 g / L trisodium phosphate, 7.5 g / L sodium silicate, 2 ml / L octylphenol polyoxyethylene ether-10, and deionized water. The temperature of the chemical degreasing solution was maintained at 70°C. The aluminum alloy was immersed in the chemical degreasing solution for 7.5 minutes. It was then rinsed with deionized water at room temperature for 1 minute.

[0053] A pickling activation solution was prepared using 20 vol% nitric acid, 3 vol% hydrofluoric acid, and deionized water. The degreased aluminum alloy was immersed in the pickling activation solution at room temperature for 3 minutes. It was then rinsed with deionized water at room temperature for 1 minute.

[0054] Pre-anodization was performed in a 170 g / L sulfuric acid solution under the following conditions: titanium alloy as the anode, stainless steel plate as the cathode, constant voltage mode, voltage 15 V, temperature 20 °C, for 2.5 min. The mixture was then rinsed with deionized water at room temperature for 1 min.

[0055] An anodizing solution was prepared using 180 g / L sulfuric acid, 2 g / L antibacterial material (silver nitrate: silver ion-doped porous nano-titanium dioxide = 2:1, wherein the pore size of the silver ion-doped porous titanium dioxide is 10-50 nm and the Ag loading is 2 wt.%), and deionized water. A titanium alloy was used as the anode, and a stainless steel plate as the cathode. A constant voltage mode was employed: 16 V, 20 °C, and anodizing for 10 min. The mixture was then rinsed with deionized water at room temperature for 1 min and dried at 80 °C for 10 min.

[0056] A sealing solution was prepared using 60% polyethylene glycol, 35% sodium methylene dimethylnaphthalene sulfonate, and 5% silver ion-doped porous nano-titanium dioxide, and sealed at 20°C for 5 min.

[0057] Cur at 120℃ for 45 minutes. Example 4

[0058] This embodiment provides a method for preparing an antibacterial titanium alloy: A chemical degreasing solution was prepared using 20 g / L sodium hydroxide, 25 g / L sodium carbonate, 40 g / L trisodium phosphate, 7.5 g / L sodium silicate, 2 ml / L octylphenol polyoxyethylene ether-10, and deionized water. The temperature of the chemical degreasing solution was maintained at 70°C. The aluminum alloy was immersed in the chemical degreasing solution for 7.5 minutes. It was then rinsed with deionized water at room temperature for 1 minute.

[0059] A pickling activation solution was prepared using 20 vol% nitric acid, 3 vol% hydrofluoric acid, and deionized water. The degreased aluminum alloy was immersed in the pickling activation solution at room temperature for 3 minutes. It was then rinsed with deionized water at room temperature for 1 minute.

[0060] An anodizing solution was prepared using 180 g / L sulfuric acid, 2 g / L antibacterial material (silver nitrate: silver ion-doped porous nano-titanium dioxide = 2:1, wherein the pore size of the silver ion-doped porous titanium dioxide is 10-50 nm and the Ag loading is 2 wt.%), and deionized water. A titanium alloy was used as the anode, and a stainless steel plate as the cathode. A constant voltage mode was employed: 16 V, 20 °C, and anodizing for 10 min. The mixture was then rinsed with deionized water at room temperature for 1 min and dried at 80 °C for 10 min.

[0061] A sealing solution was prepared using 60% polyethylene glycol, 35% sodium methylene dimethylnaphthalene sulfonate, and 5% silver ion-doped porous nano-titanium dioxide, and sealed at 20°C for 5 min.

[0062] Cur at 120℃ for 45 minutes.

[0063] The antibacterial titanium alloys prepared in the above embodiments were subjected to the following performance tests, and the results are shown in Table 1.

[0064] The antibacterial rate against Escherichia coli and Staphylococcus aureus was tested according to GB / T 21510-2008 "Test Method for Antibacterial Properties of Nano-Inorganic Materials"; Adhesion was tested according to GB / T 9286-2021 "Paints and Varnishes - Cross-cut Test"; The hardness was tested according to GB / T 9790-2021 "Microhardness Tests of Metallic Materials and Other Inorganic Coatings".

[0065] Table 1 ; As shown in Table 1, the antibacterial properties of the antibacterial titanium alloys in Examples 1-4 are all above 99.9%. Compared with Example 4, Examples 1-3 demonstrate that pre-anodization provides a chemical barrier, preventing the antibacterial substance from penetrating to the matrix interface, avoiding interface embrittlement and hardness reduction caused by impurity accumulation, and thus improving hardness. Furthermore, the gradient structure of the matrix, dense pre-oxidized layer, and anodized layer containing antibacterial substance allows for a smooth transition in the performance of the antibacterial titanium alloy, alleviating internal stress concentration and improving adhesion and hardness. Compared with Example 3, Example 3 has a lower concentration of antibacterial substance, so its antibacterial performance is also slightly lower. However, Example 3 has higher hardness than Example 2. This is partly due to the lower concentration of antibacterial substance resulting in a denser structure, and partly due to the fact that sodium methylene dimethylnaphthalene sulfonate dispersant can more effectively exert its dispersing and wetting effects under low concentration antibacterial substance conditions.

[0066] The present application has been described in detail above with reference to specific embodiments and exemplary examples; however, these descriptions should not be construed as limiting the present application. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and implementation methods of the present application without departing from the spirit and scope of the present application, and all such modifications and improvements fall within the scope of the present application. The scope of protection of the present application is determined by the appended claims.

Claims

1. A method for preparing an antibacterial titanium alloy, characterized in that, Includes the following steps: S1. Chemical degreasing, primary water washing, acid pickling activation, and secondary water washing are performed on the titanium alloy substrate. S2. Anodize the pretreated titanium alloy substrate to prepare an antibacterial oxide film. S3. The antibacterial oxide film is sealed and cured.

2. The method for preparing the antibacterial titanium alloy according to claim 1, characterized in that, In step S1, The chemical degreasing involves immersing the titanium alloy in a chemical degreasing solution for 5-10 minutes. The chemical degreasing solution comprises 10-30 g / L sodium hydroxide, 20-30 g / L sodium carbonate, 30-50 g / L trisodium phosphate, 5-10 g / L sodium silicate, 1-3 ml / L octylphenol polyoxyethylene ether-10, and the balance being deionized water. The temperature of the chemical degreasing solution is 60-80℃.

3. The method for preparing the antibacterial titanium alloy according to claim 1, characterized in that, In step S1, The pickling and activation process involves immersing the titanium alloy in the pickling and activation solution for 0.5-10 minutes. The pickling and activating solution comprises 15-30 vol% nitric acid, 1-5 vol% hydrofluoric acid, and the remainder deionized water. The temperature of the pickling and activating solution is 20-25℃.

4. The method for preparing the antibacterial titanium alloy according to claim 1, characterized in that, After step S1 and before step S2, the process also includes pre-anodizing the titanium alloy. The pre-anodization is performed using a titanium alloy as the anode and a stainless steel plate or lead plate as the cathode under constant voltage conditions, wherein the voltage is 1-30V, the pre-anodization time is 1-5min, and the pre-anodization temperature is 20-30℃.

5. The method for preparing the antibacterial titanium alloy according to claim 1, characterized in that, In step S2, The anodizing liquid consists of 160-220 g / L sulfuric acid, 1-5 g / L antibacterial substance, and the remainder being deionized water; The antibacterial substance is silver nitrate and silver ion-doped porous titanium dioxide.

6. The method for preparing the antibacterial titanium alloy according to claim 5, characterized in that, In step S2, The ratio of silver nitrate to silver ion-doped porous titanium dioxide is 1-3:1-2. The silver ion-doped porous titanium dioxide has a pore size of 10-50 nm and an Ag loading of 1-3 wt.%. The anodizing is performed using a titanium alloy as the anode and a stainless steel plate or lead plate as the cathode under constant voltage conditions, wherein the voltage is 1-100V, the anodizing time is 1-10min, and the anodizing temperature is 20-30℃.

7. The method for preparing the antibacterial titanium alloy according to claim 1, characterized in that, In step S3, The sealed solution consists of 50-70 wt.% alcohol, 30-40 wt.% dispersant, and 1-5 wt.% silver ion-doped porous nano-titanium dioxide. The sealing process takes 3-10 minutes; The temperature for the sealing process is 20-25℃.

8. The method for preparing the antibacterial titanium alloy according to claim 7, characterized in that, In step S3, The alcohol is selected from at least one of sorbitol, glycerol, propylene glycol, isopropanol, and polyethylene glycol; The dispersant is selected from at least one of sodium methylene bis(naphthalene) sulfonate, sodium methylene bis(naphthalene) sulfonate, nanocellulose, sodium cellulose sulfonate, and sodium dodecylbenzene sulfonate.

9. The method for preparing the antibacterial titanium alloy according to claim 1, characterized in that, In step S3, The curing temperature is 100-150℃; the curing time is 30-60 minutes.

10. The antibacterial titanium alloy prepared by the preparation method according to any one of claims 1-9.