Titanium-zirconium alloy wire material special for oral implant and preparation method thereof

Abstract

The application provides a titanium-zirconium alloy wire special for oral implant and a preparation method, and relates to the technical field of titanium-zirconium alloy wires.The titanium-zirconium alloy wire comprises the following components: Zr: 13-18 wt%, O: 0.14-0.20 wt%, the balance of Ti and inevitable impurities.Through multi-directional multi-fire forging, rolling, drawing and other processes, as well as reasonable deformation distribution and special finishing methods such as electric straightening and polishing, the performance of the product is stable, the strength, plasticity and matching are good, and the product can meet the special requirements of oral implants.

Description

Technical Field

[0001] This invention relates to the field of titanium-zirconium alloy wire technology, and in particular to a titanium-zirconium alloy wire for dental implants and its preparation method. Background Technology

[0002] Dental implants have become a routine treatment option for replacing missing teeth. Among implants, pure titanium is the most widely used material due to its advantages such as low density, good corrosion resistance, and excellent biocompatibility. However, pure titanium has insufficient mechanical strength, resulting in a relatively high risk of stress fatigue fracture, which significantly reduces the lifespan of dental implants and makes it difficult to meet clinical needs. Furthermore, pure titanium implants have a diameter of 3.5 mm or greater, making them almost impossible to implant in narrow jawbones or on anterior teeth, which greatly limits their application.

[0003] To compensate for the insufficient mechanical properties of pure titanium and to obtain implant materials with small diameters and high strength, many researchers have added different elements to pure titanium to obtain implant materials with superior performance compared to pure titanium. Among the many alloying elements, Ti, like Zr, belongs to Group IVB and has similar chemical properties. In addition, the Ti-Zr binary alloy phase diagram shows that both the high-temperature β phase and the low-temperature α phase are completely dissolved, forming α-titanium alloys in various proportions. This increases the mechanical strength of the implant, such as tensile strength, hardness, and flexural strength, and improves the corrosion potential and wear resistance of Ti. Summary of the Invention

[0004] In view of this, the present invention provides a titanium-zirconium alloy wire for dental implants and a method for its preparation, which is used to meet the clinical needs of high-strength narrow-diameter implants (<3.5mm). It has advantages such as reducing the use of bone augmentation surgery, alleviating patient pain, and realizing the domestic substitution of pure titanium for dental implant materials.

[0005] The first objective of this invention is to provide a titanium-zirconium alloy wire for dental implants. The titanium-zirconium alloy wire comprises the following components by mass percentage: Zr: 13-18%, O: 0.14-0.20%, with the balance being Ti and unavoidable impurities.

[0006] Preferably, the Zr is added in the form of industrial grade 1 sponge zirconium; the O is added in the form of titanium dioxide; and the Ti is added in the form of grade 0 sponge titanium and titanium dioxide.

[0007] Preferably, the mass percentage of Zr can be 13%, 14%, 15%, 16%, 17%, 18%, etc.

[0008] Preferably, the mass percentage of O can be 0.14%, 0.15%, 0.16%, 0.17%, 0.18%, 0.19%, 0.20%, etc.

[0009] Preferably, the grade 0 sponge titanium raw material is selected from grade 0 small-particle sponge titanium that conforms to the standard GB / T2524-2010, with a particle size of 0.83-12.7mm.

[0010] Preferably, the industrial grade 1 sponge zirconium raw material is selected from industrial grade HZr-1 sponge zirconium that conforms to the YS / T397-2015 standard, with a particle size of less than or equal to 3.0 mm.

[0011] Preferably, the hydrogen content of the titanium-zirconium alloy is less than or equal to 0.006%.

[0012] A second objective of this invention is to provide a method for preparing a titanium-zirconium alloy wire for dental implants, comprising the following steps:

[0013] S1. Ingot smelting: The titanium-zirconium alloy wire according to the composition of claim 1 is mixed evenly and pressed into an electrode, and then smelted into an ingot in a vacuum consumable arc furnace.

[0014] S2. Forging: After sawing off the risers and bottoms and machining the finished ingot, in order to ensure complete crushing of alloy grains, the billet is forged and heated to 960-1000℃, held for 90-120min, and upsetting and drawing are performed 3 times, with a total forging ratio in the range of 5.0-7.0; the drawing forging is heated to 910-950℃ and held for 60-90min, with a total forging ratio in the range of 2.0-4.0.

[0015] S3. Rolling: Heat the square billet after grinding surface defects to 800-870℃, hold for 30-70 minutes, and hot roll it into a bar billet with a total deformation of not less than 70%.

[0016] S4. Hot drawing: The billet is heated in a heating zone of 3-6m in length and at a heating temperature of 720-780℃. The billet is then drawn to a specification of Φ6.00mm or less through multiple dies and small deformation.

[0017] S5. Heat treatment: Anneal the cut hot-drawn wire material. The heat treatment procedure is to heat to 600-700℃, hold for 40-90 minutes, and air cool to room temperature.

[0018] S6. Straightening and polishing: Obtain the required dimensions of the titanium-zirconium alloy wire.

[0019] Preferably, the melting process in step S1 is performed three times, with the vacuum degree of the final melting being less than 1.0 × 10⁻⁶. -1 Those skilled in the art can reasonably configure the size of the ingot according to the finished product size and actual conditions, and the present invention does not impose any special limitations on this.

[0020] Preferably, in step S2, a 1600-4500T press is used for forging, and the process is carried out by a combination of three upsetting and three drawing processes plus drawing and forging.

[0021] Preferably, the heating process in step S3 is further preferably 830-870℃, and the temperature is maintained for 40-70 minutes.

[0022] Preferably, in step S4, a tubular electric furnace is used for heating, the lubricant used in the hot drawing process is graphite emulsion, the hot drawing speed is in the range of 1-3 m / min, and the hot drawing deformation is controlled in the range of 0.3-0.5 mm / dies; the specifications of the bar blank obtained by hot drawing are the finished product specifications + (0.2-0.5) mm (here, specifications refer to diameter).

[0023] Preferably, the heat treatment equipment in step S5 is an electric furnace, and the environment inside the electric furnace is a slightly oxidizing atmosphere.

[0024] Preferably, to ensure the straightness and surface quality of the finished product, the straightening in step S6 is specifically performed by electric straightening, with a counterweight set at 15-30 kg, a current set at 150-200 A, and a temperature set at 550-650 °C; the grinding process is performed by a centerless grinder, with the diameter reduction controlled between 0.2-0.5 mm.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] The titanium-zirconium alloy wire for dental implants provided by this invention exhibits stable and consistent room-temperature tensile properties, with a tensile strength ≥850MPa, hardness ≥250HV, grain size grade >12, and hydrogen content <0.006% in the finished wire. The titanium-zirconium alloy wire for dental implants provided by this invention has a uniform ingot chemical composition. Through multi-directional, multi-fire forging, rolling, and drawing processes, along with a reasonable deformation distribution and special finishing methods such as electrical straightening and polishing, the product exhibits stable performance, excellent strength, plasticity, and compatibility, meeting the specific requirements of dental implants. When made into titanium-zirconium implants, its performance is currently irreplaceable by pure titanium materials, demonstrating broad application prospects. Attached Figure Description

[0027] Figure 1 This is a microstructure diagram of the titanium-zirconium alloy wire with a specification of φ4.0mm in Example 1 of the present invention. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0029] Unless otherwise specified, the test methods or experimental methods described in the following examples are all conventional methods; unless otherwise specified, the raw materials and additives are obtained from conventional commercial sources or prepared by conventional methods.

[0030] Examples 1-2

[0031] A method for preparing a titanium-zirconium alloy wire for dental implants includes the following steps:

[0032] S1. Ingot smelting: "Grade 0" sponge titanium, "Industrial Grade 1" sponge zirconium and titanium dioxide powder are selected as raw materials. The alloy components are mixed evenly and then pressed into electrodes. The pressed electrode rods are smelted three times in a vacuum self-consuming melting furnace with a vacuum degree not exceeding 1.0×10-1pa, a melting current of 1400A, a melting voltage of 32V, and an AC arc stabilization current of 4A to obtain a Φ110×Lmm ingot.

[0033] The chemical composition of the ingot was analyzed, and the results are shown in Table 1:

[0034] Table 1

[0035] element Zr / ％ O / ％ Fe / % C / ％ N / ％ H / ％ This invention requires 13.0～18.0 0.15～0.20 <0.25 <0.05 <0.05 <0.008 Example 1 15.32 0.179 0.028 0.004 0.009 0.0022 Example 2 15.15 0.190 0.029 0.005 0.010 0.0027

[0036] The (α+β / β) phase transition point was determined to be 913℃ using metallographic methods, where the H element is the result of the finished product's test.

[0037] S2. Forging: After sawing off the risers and bottoms and machining the finished ingot, in order to ensure complete crushing of alloy grains, the smelted ingot is forged in two stages. The initial forging is heated to 980℃ and held for 90 minutes, with 3 upsetting and 3 drawing stages, and the total forging ratio is 6.0. The drawing forging is heated to 930℃ and held for 60 minutes, with the total forging ratio is 3.3, to obtain the forged bar billet.

[0038] S3. Roll the forged billet: Heat the square billet after grinding the surface defects to 850℃, hold for 40 minutes, and hot roll it into a billet with a total deformation of 95%.

[0039] S4. Hot drawing: The billet is heated, and the heating temperature is gradually reduced from 780℃ to 740℃. The drawing speed is 1.5m / min, and the hot drawing deformation is controlled at 0.4mm / dies. The billet is drawn to a specification of Φ6.00mm or less.

[0040] S5. Heat treatment: Anneal the cut hot-drawn wire material. The heat treatment procedure is to heat to 630℃, hold for 60 minutes, and air cool to room temperature.

[0041] S6. Straightening and polishing: The electric straightening counterweight is set to 30kg, the current is set to 180A, and the temperature is 600℃; the grinding process uses a centerless grinder, and the diameter reduction is controlled at 0.4mm to obtain the required dimensions of the titanium-zirconium alloy wire.

[0042] The mechanical properties, microstructure, grain size, and hardness of the titanium-zirconium alloy wires prepared in Examples 1-2 were tested. The mechanical property testing followed the standards GB / T228.1-2010; microstructure testing followed GB / T5168-2020; grain size rating followed GB / T6394-2017; and hardness testing followed ASTM E92-2017. The test results are shown in Table 2.

[0043] Table 2

[0044]

[0045]

[0046] Comparative Example 1

[0047] The difference between Comparative Example 1 and Examples 1-2 is that the alloying elements in the sponge titanium were set according to the composition ratio of TA4G in GB / T3620.1-2016 "Titanium and Titanium Alloys Grades and Chemical Compositions", and "Grade 0" sponge titanium, ferrotitanium alloy and titanium dioxide powder were selected as raw materials.

[0048] The chemical composition of the ingot was analyzed, and the results are shown in Table 3:

[0049] Table 3

[0050] element O / ％ Fe / % C / ％ N / ％ H / ％ Standard range <0.40 <0.50 <0.08 <0.05 <0.015 Detection value 0.25 0.324 0.007 0.007 0.0025

[0051] The (α+β / β) phase transition point was determined to be 904℃ using metallographic methods, with the H element being the result of the finished product's testing.

[0052] The mechanical properties, grain size, and hardness of the TA4G wire prepared in Comparative Example 1 were tested. The mechanical property testing followed the standard GB / T228.1-2010; the grain size rating followed GB / T6394-2017; and the hardness testing followed ASTM E92-2017. The test results are shown in Table 4.

[0053] Table 4

[0054]

[0055]

[0056] Comparative Examples 2-3

[0057] The difference between Comparative Example 2 and Examples 1-2 is that a Φ110×Lmm ingot was obtained by VAR2 melting; the forging was heated to 980℃ and held for 90min, and upsetting and drawing were carried out in one heat, with a total forging ratio of 2.9; the hot drawing deformation was controlled at 0.5mm / die.

[0058] The difference between Comparative Example 3 and Examples 1-2 is that a Φ110×Lmm ingot was obtained by VAR2 melting; the forging was heated to 980℃ and held for 90min, and upsetting and drawing were carried out in one heat, with a total forging ratio of 2.9; the hot drawing deformation was controlled at 0.5mm / die; the heat treatment procedure was to heat to 700℃, hold for 60min, and air cool to room temperature.

[0059] The chemical composition of the ingot was analyzed, and the results are shown in Table 5:

[0060] Table 5

[0061] element Zr / ％ O / ％ Fe / % C / ％ N / ％ H / ％ This invention requires 13.0～18.0 0.15～0.20 <0.25 <0.05 <0.05 <0.008 Comparative Example 2 16.02 0.165 0.030 0.006 0.014 0.0025 Comparative Example 3 15.70 0.18 0.031 0.005 0.010 0.0030

[0062] The mechanical properties, grain size, and hardness of the wires obtained in Comparative Examples 2-3 were tested. The mechanical property testing followed the standard GB / T228.1-2010; the grain size rating followed GB / T6394-2017; and the hardness testing followed ASTM E92-2017. The test results are shown in Table 6.

[0063] Table 6

[0064]

[0065]

[0066] Comparison shows that "Comparative Example 1" and "Examples 1-2" used the same process to produce the wire. The wire produced in "Examples 1-2" has an elastic modulus and plasticity comparable to "Comparative Example 1," but its strength is more than 28% higher, and its grain size is significantly higher. The titanium-zirconium implant material prepared by this invention has obvious advantages and can replace the application of TA4 pure titanium dental implants.

[0067] In "Comparative Example 2-3", the compositional range of the main element Zr after two smeltings was within 0.32% and the compositional range of O was 0.015%. In contrast, in "Example 1-2", after three smeltings, the compositional range of the main element Zr was within 0.17% and the compositional range of O was 0.011%. "Example 1-2" was significantly better than "Comparative Example 2-3" in terms of compositional uniformity.

[0068] The forging process of "Comparative Example 2-3" uses a single upsetting and drawing forging process, and the finished product has a grain size of 8.0-9.0 grade. In contrast, "Example 1-2" uses a two-upsetting and three-drawing process for forging, and the finished product has a grain size of 14-15 grade, which is much higher than that of "Comparative Example 2-3".

[0069] Compared to Examples 1-2, Comparative Examples 2-3 show a decrease of approximately 100 MPa in tensile strength and approximately 40 HV10 in hardness. The preparation process of this invention is superior, resulting in highly uniform material composition, excellent mechanical properties, and moderate hardness, meeting the needs of implants in narrow jaws, anterior incisors, and high occlusal areas.

[0070] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a titanium-zirconium alloy wire for dental implants, characterized in that, Includes the following steps: S1. Ingot smelting: According to the composition of titanium-zirconium alloy wire, the materials are uniformly mixed and pressed into electrodes, which are then smelted into ingots in a vacuum consumable arc furnace. S2. Forging: After sawing off the risers and bottoms and machining the finished ingot, heat the billet forging to 960-1000℃ and hold for 90-120 minutes, using 3 upsetting and 3 drawing operations, with a total forging ratio in the range of 5.0-7.0; for drawing forging, heat to 910-950℃ and hold for 60-90 minutes, with a total forging ratio in the range of 2.0-4.

0. S3. Rolling: Heat the square billet after grinding surface defects to 800-870℃, hold for 30-70 minutes, and hot roll it into a bar billet with a total deformation of not less than 70%. S4. Hot drawing: The billet is heated in a heating zone of 3-6m in length and at a heating temperature of 720-780℃. The billet is then drawn to a specification of Φ6.00mm or less through multiple dies and small deformation. S5. Heat treatment: Anneal the cut hot-drawn wire material. The heat treatment procedure is to heat to 600-700℃, hold for 40-90 minutes, and air cool to room temperature. S6. Straightening and polishing: Obtain the required dimensions of the titanium-zirconium alloy wire; The titanium-zirconium alloy wire comprises the following components by mass percentage: Zr: 13-18%, O: 0.14-0.20%, with the balance being Ti and unavoidable impurities.

2. The method for preparing the titanium-zirconium alloy wire for dental implants according to claim 1, characterized in that, The Zr is added in the form of industrial grade 1 sponge zirconium.

3. The method for preparing the titanium-zirconium alloy wire for dental implants according to claim 1, characterized in that, The O is added in the form of titanium dioxide.

4. The method for preparing the titanium-zirconium alloy wire for dental implants according to claim 1, characterized in that, The Ti was added in the form of grade 0 sponge titanium and titanium dioxide.

5. The method for preparing the titanium-zirconium alloy wire for dental implants according to claim 1, characterized in that, The melting process in step S1 is performed three times, with the vacuum degree of the final melting being less than 1.0 × 10⁻⁶. -1 pa.

6. The method for preparing the titanium-zirconium alloy wire for dental implants according to claim 1, characterized in that, In step S2, a 1600-4500T press is used for forging.

7. The method for preparing the titanium-zirconium alloy wire for dental implants according to claim 1, characterized in that, The lubricant used in the hot drawing process described in step S4 is graphite emulsion, the hot drawing speed is in the range of 1-3 m / min, and the hot drawing deformation is controlled at 0.3-0.5 mm / die.

8. The method for preparing the titanium-zirconium alloy wire for dental implants according to claim 1, characterized in that, The heat treatment equipment mentioned in step S5 is an electric furnace, and the environment inside the electric furnace is a slightly oxidizing atmosphere.

9. The method for preparing the titanium-zirconium alloy wire for dental implants according to claim 1, characterized in that, The straightening described in step S6 is specifically electric straightening, with a counterweight set to 15-30kg, a current set to 150-200A, and a temperature set to 550-650℃; the grinding process uses a centerless grinder, with the diameter reduction controlled between 0.2-0.5mm.

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