Production method of Ti6Al4V5CuELI antibacterial titanium alloy plate for implantation

Abstract

The invention provides a production method of a Ti6Al4V5CuELI antibacterial titanium alloy plate for implantation, and belongs to the technical field of antibacterial titanium alloy preparation. The preparation method comprises the following steps: firstly, proportioning according to the components of Ti6Al4V5CuELI antibacterial titanium, and smelting into a cast ingot; the Ti6Al4V5CuELI antibacterial titanium alloy plate is obtained by sequentially carrying out cogging forging, hot rolling, finished product rolling and finished product heat treatment and adjusting specific treatment parameters, the titanium alloy plate prepared through the method is stable in performance, the performance ranges from 5.0 mm to 25.0 mm, the tensile strength ranges from 1100 MPa to 1200 MPa, the yield strength ranges from 1050 MPa to 1150 MPa, the strength and plasticity matching performance is good, and the antibacterial requirement is met.

Description

Technical Field

[0001] The invention relates to the technical field of antibacterial titanium alloy preparation, and in particular to a production method of a Ti6Al4V5CuELI antibacterial titanium alloy plate for implantation. Background Art

[0002] Copper-containing antibacterial titanium alloy is a medical metal material with antibacterial properties. By adding an appropriate amount of copper to the titanium alloy, the titanium alloy is endowed with antibacterial function, which can effectively inhibit the growth and reproduction of bacteria on the surface of the material. Copper-containing antibacterial titanium alloy has broad application prospects in clinical fields such as orthopedics and dentistry. The application of copper-containing antibacterial titanium alloy can effectively reduce the risk of infection caused by implants and improve the rehabilitation effect and quality of life of patients.

[0003] The development of antibacterial titanium and titanium alloys for surgical implants is mainly to solve the problem of bacterial infection caused by implanted medical devices during use and after surgery. Ti6Al4V and Ti6Al7Nb are typical representatives of antibacterial titanium alloys currently used in clinical practice. As surgical repair materials such as artificial joints, bone trauma products, spinal orthopedic internal fixation systems, and oral orthodontic products, they have a long history of clinical application. The related infection problems caused by implants in the human body have become a problem that needs to be solved urgently in clinical practice. The development of new titanium alloy implant materials with overall antibacterial properties is of great significance in clinical applications.

[0004] Ti6Al4V5CuELI is a new type of medical titanium alloy with anti-infection function. It utilizes the strong bactericidal function of copper (Cu) and is designed and developed based on the existing medical Ti6Al4V. A large number of related studies have not only proved that copper-containing antibacterial titanium alloys have the effect of inhibiting bacterial infection and excellent biocompatibility both in vivo and in vitro, but also explored the antibacterial mechanism of copper-containing antibacterial titanium alloys from multiple angles such as bacterial membrane structure observation, oxidative stress response, respiration, gene integrity, and toxicity.

[0005] However, existing research shows that copper-containing antibacterial titanium alloy is a titanium alloy that can be strengthened by copper-containing phase dispersion and second phase strengthening. During the processing, the presence of copper elements accelerates the heat loss during the hot processing of the copper-containing titanium alloy material, and the difficulty of controlling hot processing deformation increases. During room temperature processing, a large amount of dispersed copper-containing second phase is precipitated, which leads to a decrease in the mechanical processing performance of the material. Summary of the invention

[0006] In view of this, the present invention provides a method for producing a Ti6Al4V5CuELI antibacterial titanium alloy plate for implantation. The titanium alloy plate prepared by the method has stable performance, good strength and plasticity matching, and meets antibacterial requirements.

[0007] The production method of the Ti6Al4V5CuELI antibacterial titanium alloy plate for implantation of the present invention comprises the following steps:

[0008] (1) Melting and ingot casting: taking pure titanium raw material, adding intermediate alloy according to the composition of Ti6Al4V5CuELI antibacterial titanium, pressing into electrodes, and melting into ingot casting;

[0009] (2) Open forging: The surface is peeled, the riser and bottom are removed, and the ingot is heated to 50-100°C above the β phase transformation point in an electric furnace. After keeping the temperature for 100-150 minutes, forging is carried out, and surface defects are ground to obtain a blank;

[0010] (3) hot rolling: the billet is heated to the α+β two-phase region and kept warm for 90-180 min, and then hot rolled to obtain slab 1, and then surface defects are repaired; the slab that has passed the repair is heated again to the α+β two-phase region and kept warm for 30-60 min, and then hot rolled to obtain slab 2;

[0011] (4) Finished product rolling: the slab 2 obtained in step (3) is heated to 80-100° C. below the phase transformation point of the titanium alloy, kept at this temperature for 80-100 min, and hot-rolled in multiple passes with a small amount of deformation, with the deformation amount of each pass being 8%-12%, to obtain a finished slab;

[0012] (5) Finished product heat treatment: annealing in the atmosphere and air cooling; the annealing temperature is 740-750° C. and the holding time is 60-100 min.

[0013] Preferably, the pure titanium raw material in step (1) is sponge titanium of grade 1 or above (in compliance with GB / T 2524-2010 standard).

[0014] Preferably, the intermediate alloy in step (1) comprises pure Al, copper-titanium alloy and aluminum-vanadium alloy.

[0015] Preferably, the smelting in step (1) is carried out in a vacuum consumable arc furnace, and the smelting is performed three times.

[0016] More preferably, the smelting temperature is 2000-2200°C and the time is 5-7 hours.

[0017] Preferably, the diameter of the ingot in step (1) is 350-700 mm.

[0018] Preferably, the forging method in step (2) is: heating the ingot to above the β phase transformation point in an electric furnace and keeping it warm for 100-150 minutes. After it is completely burned through, it is multi-directionally forged and deformed at a pressure of 3000-4500 tons to obtain a square billet.

[0019] More preferably, the size of the billet is δ150mm×550mm×~1300mm.

[0020] Preferably, the thickness of the slab 1 in step (3) is 3-20 times the thickness of the finished product.

[0021] Preferably, the thickness of the slab 2 in step (3) is 1 to 10 mm thicker than the thickness of the finished product.

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

[0023] The present invention provides a production method of Ti6Al4V5CuELI antibacterial titanium alloy sheet for implantation, and adopts a unique component formula and processing technology to obtain a Ti6Al4V5CuELI antibacterial titanium alloy sheet for implantation. The material has stable performance, wherein 5.0-10mm, tensile strength 1100-1250MPa, yield strength 1000-1150MPa, strength, and plasticity matching are good, and the antibacterial requirements are met. When it is made into an implant, its antibacterial performance cannot be replaced by other metal materials at present, and it has broad application prospects. The present invention adopts three smelting, forging, rolling, and the finished product is then subjected to 730-750℃ / 60min, and the plate obtained after air cooling has stable performance, and strength and plasticity matching are good. The present invention is different from the existing preparation method. The finished product is cooled by air cooling after annealing. The air cooling method can well avoid the aging effect of the plate produced in the low temperature stage, obtain better plasticity, and the strength will not be reduced. DETAILED DESCRIPTION

[0024] The present invention will be further described below in conjunction with the embodiments.

[0025] Example 1

[0026] A method for producing a Ti6Al4V5CuELI antibacterial titanium alloy sheet for implantation, comprising the following steps:

[0027] (1) Melting ingot: Take "grade 0" sponge titanium as raw material, add pure Al beans, Ti35Cu and Al55V according to the composition of Ti6Al4V5CuELI antibacterial titanium, press into electrodes, and use vacuum consumable arc furnace for three smelting to obtain titanium alloy ingot with a diameter of Φ380; the smelting temperature is 2200°C and the time is 6.5h

[0028] The chemical composition analysis of the titanium alloy ingot of Example 1 is shown in Table 1, and the balance is Ti and unavoidable impurities. It complies with the standard of Antibacterial Titanium Alloy Processing Materials for Surgical Implants Part 2: Ti6Al4V5CuELI, T / CSBM 0021-2022, and has uniform composition.

[0029] Table 1 Chemical composition of Ti6Al4V5CuELI ingot in Example 1 (in mass percentage, %)

[0030]

[0031] (2) Billet forging: The (α+β / β) phase transition point is 929°C as measured by metallographic method. After ultrasonic flaw detection, the surface of the ingot is peeled, and the riser and bottom are removed. Then, the ingot is heated to above the β phase transition point (1000°C) in an electric furnace and kept warm for 120 minutes. After being completely burned through, it is multi-directionally forged under the high pressure of a 4500-ton press and deformed into the required billet with dimensions of 150 mm × 550 mm × 1300 mm.

[0032] (3) Hot rolling: The billet is heated to the α+β two-phase region (830°C) and kept at this temperature for 90 min, and then hot rolled to obtain a slab 1 (δ33±0.5 mm), cut, and perform surface defect grinding; the slab that passes the grinding is heated again to the α+β two-phase region and kept at this temperature for 60 min, and then hot rolled to obtain a slab 2 with δ15±0.5 mm and δ7.0±0.5 mm;

[0033] (4) Finished product rolling: The slab 2 obtained in step (3) is heated to below the phase transformation point of the titanium alloy (850° C. for 90 min), and hot rolled in multiple passes with small deformation, with the deformation of each pass being 8-12%, to obtain finished slabs with δ10.7 and δ5.4 mm;

[0034] (5) Finished product heat treatment: annealing and pressing for leveling in an atmospheric furnace, annealing temperature of 740°C, holding time of 60 min, air cooling, unevenness of no more than 3 mm / m.

[0035] Sanding was performed on a sanding machine until the finished plate size was δ5.0 and δ10.0 mm.

[0036] The mechanical properties of the two different specifications of the plates prepared in Example 1 were tested, and the test results are shown in Tables 2 and 3.

[0037] Table 2 Mechanical properties of 5.0 mm thick plate in Example 1

[0038]

[0039] Table 3 Mechanical properties of 10.0 mm thick plate in Example 1

[0040]

[0041] It can be seen from Table 2 and Table 3 that the performance data of the sheet prepared in Example 1 are relatively concentrated. When the sheet thickness is 5.0-10 mm, the tensile strength is 1100-1250 MPa, the yield strength is 1100-1150 MPa, the elongation after fracture is 13.5-15.5, the cross-sectional shrinkage is 27-31, and the performance stability is good. The room temperature tensile performance test results meet the requirements of T / CSBM 0021-2022 standard.

[0042] Comparative Example 1

[0043] The composition of the raw materials was changed, "grade 0" titanium sponge was selected as the raw material, pure Al beans and Al55V particles were used as alloying elements, and a Ti6Al4VELI titanium alloy was prepared, the chemical composition of which is shown in Table 4, and the remainder is Ti and unavoidable impurities. The preparation method is the same as in Example 1.

[0044] Table 4 Chemical composition of Ti6Al4VELI ingot in comparative example 1 (in mass percentage, %)

[0045] Al％ V％ Fe% C％ N％ O％ H％ Require 5.5-6.5 3.5-4.5 ≤0.25 ≤0.08 ≤0.03 ≤0.13 ≤0.008 Comparative Example 1 6.26 4.26 0.163 0.009 0.009 0.115 0.0006

[0046] The mechanical properties of the finished plate of Example 1 were tested, and the results are shown in Tables 5 and 6.

[0047] Table 5 Mechanical properties of 5.0 mm thick plate in comparative example 1

[0048]

[0049] Table 6 Mechanical properties of 10.0 mm thick plate in comparative example 1

[0050]

[0051]

[0052] Comparative Example 2

[0053] The parameters of the preparation process were changed to prepare a Ti6Al4V5CuELI antibacterial titanium alloy plate. The difference was that in Comparative Example 2, the plate was heated in an electric furnace to below the phase transition point (850°C) and kept warm for 150 minutes, and then rolled to δ10.7 and δ5.4 mm through multiple passes, and the deformation rate of each pass was controlled at 8%-12%.

[0054] The mechanical properties of the finished plate of Example 2 were tested, and the results are shown in Tables 7 and 8.

[0055] Table 7 Mechanical properties of 5.0 mm thick plate in comparative example 2

[0056]

[0057] Table 8 Mechanical properties of 10.0 mm thick plate in comparative example 2

[0058]

[0059] Comparative Example 3

[0060] The parameters of the preparation process were changed to prepare a Ti6Al4V5CuELI antibacterial titanium alloy plate. The difference was that the slab after hot rolling in Comparative Example 3 was annealed and pressed flat in an atmospheric furnace, the annealing temperature was 720°C, the holding time was 60min, and it was air-cooled, and the unevenness was no more than 3mm / m.

[0061] The mechanical properties of the finished plate of Example 3 were tested, and the results are shown in Tables 9 and 10.

[0062] Table 9 Mechanical properties of 5.0 mm thick plate in comparative example 2

[0063]

[0064] Table 10 Mechanical properties of 10.0 mm thick plate in comparative example 2

[0065]

[0066] Comparative Example 4

[0067] The parameters of the preparation process were changed to prepare a Ti6Al4V5CuELI antibacterial titanium alloy plate. The difference was that the slab after hot rolling in Comparative Example 4 was annealed and pressed flat in an atmospheric furnace, the annealing temperature was 760°C, the holding time was 60 min, and it was air-cooled, and the unevenness was no more than 3 mm / m.

[0068] The mechanical properties of the finished plate of Example 4 were tested, and the results are shown in Tables 11 and 12.

[0069] Table 11 Mechanical properties of 5.0 mm thick plate in comparative example 4

[0070]

[0071] Table 12 Mechanical properties of 10.0 mm thick plate in comparative example 4

[0072]

[0073] Comparative Example 5

[0074] The parameters of the preparation process were changed to prepare a Ti6Al4V5CuELI antibacterial titanium alloy plate. The difference was that the slab after hot rolling in Comparative Example 5 was annealed and pressed flat in an atmospheric furnace, the annealing temperature was 740°C, the holding time was 60 min, and it was water-cooled, and the unevenness was no more than 3 mm / m.

[0075] The mechanical properties of the finished plate of Example 5 were tested, and the results are shown in Tables 13 and 14.

[0076] Table 11 Mechanical properties of 5.0 mm thick plate in comparative example 5

[0077]

[0078] Table 12 Mechanical properties of 10.0 mm thick plate in comparative example 5

[0079]

[0080] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for producing Ti6Al4V5CuELI antibacterial titanium alloy sheet for implantation, characterized in that: The following steps are involved: (1) Melting and ingot casting: taking pure titanium raw material, adding intermediate alloy according to the composition of Ti6Al4V5CuELI antibacterial titanium, pressing into electrodes, and melting into ingot casting; (2) Open forging: The surface is peeled, the riser and bottom are removed, and the ingot is heated to 50-100°C above the β phase transformation point in an electric furnace. After keeping the temperature for 100-150 minutes, forging is carried out, and surface defects are ground to obtain a blank; (3) hot rolling: the billet is heated to the α+β two-phase region and kept warm for 90-180 min, and then hot rolled to obtain slab 1, and then surface defects are repaired; the slab that has passed the repair is heated again to the α+β two-phase region and kept warm for 30-60 min, and then hot rolled to obtain slab 2; (4) Finished product rolling: the slab 2 obtained in step (3) is heated to 80-100° C. below the phase transformation point of the titanium alloy, kept at this temperature for 80-100 min, and hot-rolled in multiple passes with a small amount of deformation, with the deformation amount of each pass being 8%-12%, to obtain a finished slab; (5) Finished product heat treatment: annealing in the atmosphere and air cooling; the annealing temperature is 730-750°C and the holding time is 60-100 min.

2. The method for producing the Ti6Al4V5CuELI antibacterial titanium alloy sheet for implantation according to claim 1, characterized in that: The pure titanium raw material in step (1) is sponge titanium of grade 1 or above.

3. The method for producing the Ti6Al4V5CuELI antibacterial titanium alloy sheet for implantation according to claim 1, characterized in that: The intermediate alloy in step (1) includes pure Al, copper-titanium alloy and aluminum-vanadium alloy.

4. The method for producing the Ti6Al4V5CuELI antibacterial titanium alloy sheet for implantation according to claim 1, characterized in that: The smelting in step (1) is carried out in a vacuum consumable arc furnace, and the smelting times are three times.

5. The method for producing the Ti6Al4V5CuELI antibacterial titanium alloy sheet for implantation according to claim 4, characterized in that: The smelting temperature is 2000-2200° C. and the smelting time is 5-7 hours.

6. The method for producing the Ti6Al4V5CuELI antibacterial titanium alloy sheet for implantation according to claim 1, characterized in that: The diameter of the ingot in step (1) is 350-700 mm.

7. The method for producing the Ti6Al4V5CuELI antibacterial titanium alloy sheet for implantation according to claim 1, characterized in that: The forging method in step (2) is as follows: the ingot is heated in an electric furnace to a temperature above the β phase transformation point and kept warm for 100-150 minutes. After the ingot is completely burned through, it is subjected to multi-directional forging and deformation at a pressure of 3000-4500 tons to obtain a square billet.

8. The method for producing the Ti6Al4V5CuELI antibacterial titanium alloy sheet for implantation according to claim 7, characterized in that: The size of the billet is δ150mm×550mm×~1300mm.

9. The method for producing the Ti6Al4V5CuELI antibacterial titanium alloy sheet for implantation according to claim 1, characterized in that: The thickness of the slab 1 in step (3) is 3-20 times the thickness of the finished product.

10. The method for producing the Ti6Al4V5CuELI antibacterial titanium alloy sheet for implantation according to claim 1, characterized in that: The thickness of the slab 2 in step (3) is 1 to 10 mm thicker than the finished product.

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