High-strength and plasticity matched titanium-zirconium-based alloy wire rich in multi-scale eutectoid compound and preparation method of high-strength and plasticity matched titanium-zirconium-based alloy wire

Abstract

The invention provides a high-strength and high-plasticity matched titanium-zirconium-based alloy wire rich in multi-scale eutectoid compounds and a preparation method of the high-strength and high-plasticity matched titanium-zirconium-based alloy wire, and belongs to the technical field of titanium alloy materials. According to the method, a titanium-zirconium-based raw material containing eutectoid beta stable elements is adopted, and a cast ingot is prepared through vacuum consumable smelting; grains are refined and high dislocation density is introduced through staged phase change region hot working of beta-phase region cogging forging, beta-phase region first-heating-number rolling and alpha + beta two-phase region second-heating-number rolling; and after drawing and sizing, a horizontal electric straightening machine is used for rapidly and electrically heating to separate out a nanoscale eutectoid compound, solid solution water quenching is combined for inducing a submicron eutectoid compound, and finally a finished product is obtained through grinding and polishing. The tensile strength of the prepared wire is larger than or equal to 850 MPa, the ductility is larger than or equal to 15%, matching of high strength and plasticity is achieved, the process is continuous and controllable, batch production is adapted, and high-performance domestic raw materials are provided for oral implants.

Description

TECHNICAL FIELD

[0001] The application relates to a high-strength and high-plasticity titanium-zirconium-based alloy wire with a multi-scale eutectoid compound and a preparation method thereof, and belongs to the technical field of titanium alloy materials. BACKGROUND

[0002] Titanium and titanium-zirconium-based alloys have become core materials in the field of medical devices due to their low density, high specific strength, excellent resistance to physiological corrosion, and biocompatibility, especially in the field of oral implants. Their non-magnetic properties and bone integration capabilities can meet the long-term implantation requirements and gradually replace traditional metal materials.

[0003] However, the synergistic improvement of strength and plasticity is the main technical bottleneck for titanium-zirconium-based alloys to be applied to oral implants: oral implants need to withstand both the instantaneous impact force during chewing and the long-term fatigue load, which cannot meet the requirements of implants serving in harsh environments. Although pure titanium widely used in the industry has excellent biocompatibility, it has low tensile strength and insufficient hardness, and is prone to fatigue deformation or implant neck breakage during long-term service. In addition, its poor wear resistance increases the risk of bacterial colonization and implant failure.

[0004] To solve the performance shortcomings of pure titanium, titanium-zirconium-based alloys have gradually become alternative materials.

[0005] Among them, Chinese Patent Application No. CN116855862A discloses a heat treatment method for TC4 titanium-zirconium-based alloy wire for medical use. The TC4 titanium-zirconium-based alloy wire will generate residual stress after multi-pass drawing and straightening, resulting in a significant decrease in Bauschinger effect and yield strength. Even if induction heating and other processes are used, the stress cannot be completely eliminated, affecting the performance stability.

[0006] In terms of microstructure control, existing methods are difficult to achieve synergistic regulation of nano and micron scales. Chinese Patent Application No. CN105238954A discloses a multi-scale dual-state structure titanium-zirconium-based alloy based on eutectic transformation and a preparation method. Although the multi-scale dual-state structure of Ti-Nb-Fe-Co-Al alloy prepared by powder metallurgy can improve the strength, the process is complex and the plasticity is limited, which is difficult to be applied to mass production of wire.

[0007] Chinese Patent Application No. CN120158647A discloses a preparation method of high-strength titanium-zirconium alloy wire. A Ti-Zr binary alloy composition is used to obtain a single fine-grained structure through "controlled temperature drawing (200-400℃) + low temperature annealing (400-600℃)", achieving a tensile strength of ≥950MPa. However, this scheme relies on single work hardening and fine-grained strengthening without a second phase strengthening mechanism, resulting in a plasticity of only ≥10%. After fine-grained, the elongation rate will further decrease to below 8% due to the accumulation of work hardening, which cannot meet the forming requirements of narrow dental implant.

[0008] In addition, for the alloy that can precipitate strengthening phase through eutectoid reaction by adding eutectoid β stabilizing elements, the traditional processing technology has insufficient control precision, which easily leads to oversize or poor distribution of precipitates. For example, the strength of Ti-7Cu alloy can reach 1090.7 MPa after heat treatment, but the elongation after fracture is only 1.7%.

[0009] Therefore, it is of great significance to develop a titanium-zirconium-based alloy wire with synergistically improved strength and plasticity to promote the localization and high performance of oral implant materials and reduce the cost of civilian implants. SUMMARY

[0010] In order to solve the above problems, a high strength and plasticity matching titanium-zirconium-based alloy wire rich in multi-scale eutectoid compounds and a preparation method thereof are provided. The multi-scale eutectoid compounds and other microstructures are precisely controlled, and the processing technology is optimized to achieve excellent matching of strength and plasticity, thereby achieving synergistic improvement of high strength and high plasticity of the titanium-zirconium-based alloy wire in the processing process.

[0011] According to an aspect of the present application, a preparation method of a high strength and plasticity matching titanium-zirconium-based alloy wire rich in multi-scale eutectoid compounds is provided, which comprises the following steps: (1) preparing titanium-zirconium-based alloy raw materials containing eutectoid β stabilizing elements, and preparing titanium-zirconium-based alloy ingots by vacuum consumable melting; (2) β phase zone breakdown forging: after holding at T β +200℃, using a fast forging machine to forge; (3) β phase zone one-fire rolling: after holding at T β +100℃, using a transverse rolling mill to roll; (4) α+β two-phase zone two-fire rolling: after holding at T β +40℃, using a continuous rolling mill to roll to obtain titanium-zirconium-based alloy rods; (5) drawing: using a disc drawing machine to draw the titanium-zirconium-based alloy rods to obtain titanium-zirconium-based alloy wires; (6) using a slide block straightening machine to process the drawn titanium-zirconium-based alloy wires to a certain size; (7) rapid heating treatment: using a horizontal electric straightening machine to rapidly electrically heat the titanium-zirconium-based alloy wires after sizing, and then air cooling, the heating temperature is 600-800℃; (8) solid solution treatment: solid solution treatment is performed on the titanium-zirconium-based alloy wires after rapid electric heating, and the temperature is controlled at 650-800℃; (9) centerless grinding and polishing are performed on the titanium-zirconium-based alloy wires after solid solution treatment to obtain the high strength and plasticity matching titanium-zirconium-based alloy wires.

[0012] Optionally, the mass percentage content of each element in the titanium-zirconium-based alloy ingot in step (1) is: Zr: 5-20%, eutectoid β stabilizing element: 0.5-10%, and the balance being Ti and unavoidable impurities. The eutectoid β stabilizing element is one of Fe, Mn, Cr, Ni and Cu.

[0013] Optionally, sponge titanium, sponge zirconium and eutectoid β stabilizing element are used as raw materials in step (1), and a titanium-zirconium-based alloy ingot is obtained through three times of melting. The melting gas leakage rate is ≤0.7 Pa / min.

[0014] Preferably, the particle size of the sponge titanium, the sponge zirconium and the eutectoid β stabilizing element is 3-8.2 mm, and more preferably, the particle size is 5 mm.

[0015] Preferably, the vacuum consumable melting is 3 times of melting, the vacuum degree of the last melting is ≤0.5 Pa, the composition segregation is controlled by stepwise arc collection, and the composition uniformity fluctuation of the ingot after melting is ≤3%.

[0016] Specifically, the vacuum consumable melting is controlled by a three-stage process: the vacuum degree of the first melting is ≤1 Pa, the current is 13-15 kA, and the voltage is 31-33 V, so as to ensure that the electrode is initially melted to form a uniform molten pool; the vacuum degree of the second melting is ≤0.8 Pa, the current is 23-25 kA, and the voltage is 32-33 V, so as to promote the composition homogenization; the vacuum degree of the third melting is ≤0.5 Pa, and the current is 25-26 kA. The segregation is reduced by stepwise arc collection (the current gradually decreases from 20 kA to 5 kA). The melting gas leakage rate is particularly controlled to be ≤0.7 Pa / min, so as to avoid the influence of gas inclusions on the subsequent eutectoid reaction. By adjusting the above parameters and matching the alloy composition, the foundation for uniform solid solution of the eutectoid element is laid, and the stability of the wire performance is ensured.

[0017] The application first ensures the uniform solid solution of the eutectoid element and Zr and Ti through three times of vacuum consumable melting, and avoids the composition segregation problem; then a two-stage rolling process (one heating + two heating) is used to introduce high dislocation density and small substructure into the alloy, so as to provide sufficient nucleation sites for the eutectoid reaction.

[0018] Optionally, the heating temperature before the breakdown forging in step (2) is T β +200℃, the holding time is 3.5-5 h, the forging temperature range is 800-1000℃, the ingot needs to be reheated 1-2 times during the forging process, and the total deformation of the breakdown forging is 60%-80%.

[0019] Specifically, by limiting the temperature of the breakdown forging, the ingot is fully softened and the grains are broken, T βThe heating temperature of 200 DEG C ensures that the ingot is completely in the beta single-phase region, and the limited holding time can make the temperature of the ingot uniform, avoiding the forging cracking caused by insufficient local temperature. Meanwhile, the limited total deformation can fully break the initial coarse grains of the ingot and eliminate the internal porosity, shrinkage and other defects of the ingot.

[0020] Optionally, in the first rolling in step (3), the rolling temperature is T β +100 DEG C, the holding time is 2-5 h, and the cumulative deformation is not less than 75%-85%.

[0021] Specifically, by limiting the first rolling parameters, the temperature of the billet after forging is uniform, which not only ensures sufficient dynamic recrystallization (further refinement of beta grains), but also avoids the cracking of the billet caused by single large deformation.

[0022] Optionally, in the second rolling in step (4), the pre-rolling temperature is T β -40 DEG C, the holding time is 0.5-2 h, the final rolling temperature is 700-850 DEG C, and the cumulative deformation is not less than 99%.

[0023] Specifically, T β -40 DEG C is in the alpha+beta two-phase region, the plasticity of the metastable beta phase at this temperature is excellent, and the alpha phase can act as a "dislocation barrier point". By limiting the parameters, it is beneficial to form the pretreatment organization of "fine beta substructure + dispersed alpha phase", which provides sufficient sites for the uniform nucleation of eutectoid phase during subsequent heat treatment, solving the problem of uneven distribution of eutectoid phase caused by insufficient dislocation density in traditional rolling.

[0024] Optionally, in step (5), the drawing speed is 1-2 m / min, and the cumulative deformation is 40-70%; in step (6), the length of the wire rod after sizing is 2500-3000 mm. The drawing is carried out at room temperature, and the room temperature is 25 DEG C.

[0025] Preferably, in step (6), a slide block straightening machine is used to size the coiled wire rod with a length of 2800 mm.

[0026] Optionally, in step (7), the time of rapid electric heating is 5-20 s, and the heating rate is ≥30 DEG C / s. After air cooling, the particle size of the nanoscale eutectoid compound is 20-200 nm, and the volume fraction is 10-16%.

[0027] Specifically, by using rapid electric heating (600-800 DEG C, 5-20 s air cooling), the eutectoid elements are promoted to diffuse and precipitate in the alpha phase to form nanoscale eutectoid phases (such as Ti2Cu and TiCr2) with a size of 50-200 nm, avoiding the coarse precipitation caused by traditional slow heating.

[0028] Optionally, the holding time of the solid solution treatment in step (8) is 0.5-2h, and the rapid cooling is water quenching, and the cooling rate is ≥100℃ / s. The particle size of the sub-micron eutectoid compound after water quenching is 200-600nm, and the volume fraction is 5-10%.

[0029] Specifically, by limiting the solid solution treatment at 650-800℃ for 0.5-2h and then water quenching, the sub-micron eutectoid phase is further induced at the α / β phase interface, and finally a multi-scale heterogeneous structure of "micron-sized α grains (ensuring structural integrity) + nanoscale internal eutectoid phase (strengthening the matrix) + sub-micron interface eutectoid phase (hindering grain boundary sliding)" is formed.

[0030] Through the synergistic effect of rapid electric heating + solid solution treatment, on the one hand, the nanoscale eutectoid phase significantly improves the strength through dislocation pinning effect; secondly, the sub-micron interface eutectoid phase hinders grain boundary sliding to avoid grain boundary cracking under large deformation; thirdly, the micron-sized α grains retain sufficient plastic deformation capacity, and through dislocation slip and grain rotation, the elongation is maintained at more than 17%.

[0031] Preferably, the amount of each centerless grinding in step (9) is less than 0.02mm.

[0032] According to another aspect of the present application, a high strength and plasticity matching titanium-zirconium-based alloy wire material rich in multi-scale eutectoid compounds is also provided, which is prepared by the above preparation method, and the tensile strength of the titanium-zirconium-based alloy wire material is ≥850MPa, and the elongation is ≥15%.

[0033] The beneficial effects of the present application include but are not limited to: 1. The preparation method of the high strength and plasticity matching titanium-zirconium-based alloy wire material rich in multi-scale eutectoid compounds, first large deformation breakdown forging is carried out above the β phase transition point, dynamic recrystallization is induced by using the high plasticity and severe deformation of the β phase region, the initial coarse grains are completely broken, fine equiaxed β grains are obtained, the fine grain foundation is laid and the defects are eliminated, then large deformation rolling is carried out in the α+β two-phase region below the phase transition point, the metastable β phase dominates and the plasticity is excellent, high dislocation density is introduced and fine substructure is formed during super large deformation, and excessive brittle phase is inhibited from precipitating, so that the rolled material with high strength and excellent plasticity is obtained.

[0034] 2. The method for preparing the high-strength and plasticity matching titanium-zirconium-based alloy wire rich in multi-scale eutectoid compounds, which is drawn at room temperature, and the large cold deformation generated by the rapid increase in dislocation density and the extreme refinement of grains / subgrains produces strong work hardening, and then through rapid electric heating technology, under limited conditions, the process precipitates nanoscale eutectoid β element compounds, which can improve the strength without sacrificing the plasticity of the alloy; meanwhile, the solid solution treatment can precipitate submicron-scale eutectoid β element compounds at the α / β phase interface, and the precipitation of such multi-scale eutectoid β element compounds combined with the α phase and the β phase will produce a significant heterogeneous structure strength effect, which can improve the strength of the alloy while endowing the alloy with sustained work hardening capacity and plastic deformation capacity.

[0035] 3. In the preparation method, the eutectoid β stabilizing elements (such as Cu and Cr) are used in cooperation with Zr elements to solve the technical bottleneck that the traditional titanium alloy is difficult to balance the strength and plasticity. The traditional titanium alloy strengthening often relies on a large amount of isomorphous β stabilizing elements, which easily leads to a sharp decrease in the plasticity of the alloy, while the eutectoid β stabilizing elements can precipitate intermetallic compounds (such as Ti2Cu and TiCr2) through eutectoid reaction during the β→α phase transition, forming a unique multi-scale strengthening structure. The addition of Zr elements can provide more nucleation sites for the eutectoid reaction through grain refinement, and on the other hand, can lower the β phase transition temperature (T β ), enhance the solid solubility of the eutectoid elements, and control the size of the precipitated phase within a limited range. In this multi-scale structure, the micron-scale α grains guarantee the plastic deformation capacity, and the nanoscale eutectoid phase improves the strength through dislocation pinning effect, realizing a breakthrough in the matching of strength and plasticity.

[0036] 3. The titanium-zirconium-based alloy wire prepared by the method has a tensile strength of ≥850 MPa and an elongation of ≥15%, and the mechanical properties fully meet and are higher than the requirements in the standard GB / T 13810-2017, providing a “high performance-high stability-low cost” domestic raw material solution for oral implants, which can reduce the price of civilian implants and promote their popularization in the primary medical field. BRIEF DESCRIPTION OF DRAWINGS

[0037] The drawings described herein are used to provide further understanding of the present application, and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application, and do not constitute an improper limitation on the present application. In the drawings: Figure 1 The backscattered electron photograph of the Ti15Zr5Cu alloy rich in multi-scale titanium-copper compounds prepared in Example 1 of the present application; Figure 2 The backscattered electron photograph of the Ti15Zr5Ni alloy rich in multi-scale titanium-copper compounds prepared in Example 2 of the present application; Figure 3 Backscattered electron image of Ti15Zr5Cr alloy prepared in Example 3 of the present application rich in multi-scale titanium copper compounds; Figure 4 Engineering stress-strain curve of Ti15Zr5Cu alloy prepared in Example 1 of the present application rich in multi-scale titanium copper compounds. DETAILED DESCRIPTION

[0038] The present application will be described in detail below with reference to examples, but the present application is not limited to these examples.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The reagents or materials used in the present application can be purchased through conventional routes, and unless otherwise specified, the reagents or materials used in the present application are used according to the conventional manner in the art or according to the product instructions. In addition, any method and material similar or equivalent to those described can be applied to the method of the present application. The preferred implementation methods and materials described in the present patent are only for demonstration.

[0040] In the present application, the β phase transition temperature (T β ) of different composition alloys is determined by differential thermal analysis (DTA): the T β of Ti-15Zr-5Cu alloy is 860-880℃, the T β of Ti-15Zr-5Ni alloy is 820-840℃, and the T β of Ti-15Zr-5Cr alloy is 790-810℃, and the difference is due to the increase of Zr content and the strong β stabilization effect of Cr and Ni.

[0041] Example 1 The preparation method of titanium-zirconium-based alloy wire includes the following steps: (1) Using sponge titanium with an average particle size of 4.5 mm, sponge zirconium, and eutectoid β stabilizing elements, the alloy composition is allocated according to the following alloy composition: Zr 15.0%, Cu 5.0%; the balance is Ti and unavoidable impurities; and the chemical composition and mass percentage of titanium-zirconium-based alloy ingot are as follows: The titanium-zirconium-based alloy ingot is obtained by three times of melting using vacuum consumable melting small current shallow pool homogenization melting technology; the vacuum consumable melting adopts three-stage process control: 1 Pa vacuum degree, 14 kA current, and 32 V voltage for the first melting; 0.8 Pa vacuum degree, 24 kA current, and 32 V voltage for the second melting; and 0.5 Pa vacuum degree, 25 kA current, and 0.5 Pa / min of melting gas leakage rate for the third melting.

[0042] (2) Adopting the fast forging machine, the titanium-zirconium base alloy ingot is forged at 1060℃ for 3.5h, and the cumulative deformation is controlled at 60%.

[0043] (3) Adopting the cross-column type rolling mill, the titanium-zirconium base alloy ingot is rolled at 970℃ for 3.5h, and the cumulative deformation is controlled at 75%.

[0044] (4) Adopting the continuous rolling mill, the titanium-zirconium base alloy ingot is rolled at 820℃ for 1.5h, and the cumulative deformation is controlled at 99.0%, and the titanium-zirconium base alloy rod is obtained.

[0045] (5) At room temperature, the titanium-zirconium base alloy rod is drawn by the disc drawing machine, the drawing speed is 2.0m / min, and the cumulative deformation is 46%.

[0046] (6) The drawn titanium-zirconium base alloy wire is processed to a fixed length by the slide block straightening machine, and the wire length is controlled at 2800mm.

[0047] (7) The fixed-length wire is quickly heated by electric straightening, the hot straightening temperature is 650℃, and the straightening time is 10s. Among them, the size of the nanoscale eutectoid compound is in the range of 20-150nm, and the volume fraction is 12%.

[0048] (8) The wire after hot straightening is solid solution treated by the bench type resistance furnace, the solid solution temperature is 800℃, the holding time is 0.5h, and the wire is immediately water quenched after being taken out of the furnace. The size of the sub-micron eutectoid compound is in the range of 200-600nm, and the volume fraction is 8%.

[0049] (9) The titanium-zirconium base alloy wire after solid solution treatment is centerless ground, and the centerless grinding amount is 0.02mm each time, and then the surface of the titanium-zirconium base alloy wire is polished to obtain the finished titanium-zirconium base alloy wire with a diameter of 5.0mm.

[0050] Example 2 The preparation method of the titanium-zirconium base alloy wire comprises the following steps: (1) Adopting the average particle size of 5.2mm of sponge titanium, sponge zirconium, and eutectoid β stabilizing element, the alloy composition is allocated according to the following alloy composition, the chemical composition and mass percentage of the titanium-zirconium base alloy ingot is Zr 15.0%, Ni 5.0%; the balance is Ti and inevitable impurities; The titanium-zirconium based alloy ingot is obtained by three times of vacuum consumable melting and small current shallow pool homogenization melting; the vacuum consumable melting adopts three-stage process control: 1 Pa vacuum degree, 14 kA current and 32 V voltage in the first time of melting; 0.8 Pa vacuum degree, 24 kA current and 32 V voltage in the second time of melting; 0.5 Pa vacuum degree, 25 kA current and 0.5 Pa / min air leakage rate in the third time of melting.

[0051] (2) The titanium-zirconium based alloy ingot is subjected to blooming forging at 1020 °C for 3.5 h by using a quick forging machine, and the cumulative deformation is controlled to be 70%.

[0052] (3) The titanium-zirconium based alloy ingot is subjected to rolling at 960 °C for 4 h by using a cross-column type rolling mill, and the cumulative deformation is controlled to be 79%.

[0053] (4) The titanium-zirconium based alloy ingot is subjected to second-time rolling at 840 °C for 2.5 h by using a continuous rolling mill, and the cumulative deformation is controlled to be 99.0% to obtain titanium-zirconium based alloy rods.

[0054] (5) The titanium-zirconium based alloy rods are subjected to drawing at room temperature by using a disc drawing machine, the drawing speed is 2.0 m / min, and the cumulative deformation is 55%.

[0055] (6) The drawn titanium-zirconium based alloy wires are subjected to sizing by using a slide block straightening machine, and the wire length is controlled to be 2800 mm.

[0056] (7) The sized wires are subjected to rapid electric heating by using electric straightening, the hot straightening temperature is 700 °C, and the straightening time is 15 s. The size of the nanoscale eutectoid compound after air cooling is in the range of 20-150 nm, and the volume fraction is 10%.

[0057] (8) The straightened wires are subjected to solid solution treatment by using a bench-type resistance furnace, the solid solution temperature is 700 °C, the holding time is 0.5 h, and the furnace is immediately water quenched after being discharged. The size of the sub-micron eutectoid compound after water quenching is in the range of 200-600 nm, and the volume fraction is 7%.

[0058] (9) The titanium-zirconium based alloy wires after solid solution treatment are subjected to centerless grinding, and the centerless grinding amount is 0.02 mm each time, and then the surface of the titanium-zirconium based alloy wires is subjected to polishing treatment to obtain Φ5.0 mm finished titanium-zirconium based alloy wires.

[0059] Example 3 The preparation method of the titanium-zirconium based alloy wire comprises the following steps: (1) The titanium sponge, the zirconium sponge and the eutectoid β stabilizing element with a particle size of 3.0 mm are used, and the alloy composition is allocated according to the following alloy composition, and the chemical composition and the mass percentage of the titanium-zirconium-based alloy ingot are as follows: Zr 20.0%, Cr 5.0%; the balance is Ti and inevitable impurities; The titanium-zirconium-based alloy ingot is obtained through three times of melting by using the vacuum consumable melting small-current shallow-pool homogenization melting technology; the vacuum consumable melting adopts three-stage process control: the first time of melting is at a vacuum degree of 1 Pa, a current of 14 kA and a voltage of 32 V; the second time of melting is at a vacuum degree of 0.8 Pa, a current of 24 kA and a voltage of 32 V; and the third time of melting is at a vacuum degree of 0.5 Pa, a current of 25 kA and a melting air leakage rate of 0.5 Pa / min.

[0060] (2) The titanium-zirconium-based alloy ingot is subjected to blooming forging at 1080 ℃ for 5 h by using a fast forging machine, and the cumulative deformation amount is controlled to be 80%.

[0061] (3) The titanium-zirconium-based alloy ingot is subjected to rolling at 980 ℃ for 4.5 h by using a cross-type rolling mill, and the cumulative deformation amount is controlled to be 80%.

[0062] (4) The titanium-zirconium-based alloy ingot is subjected to the second-time rolling at 840 ℃ for 1.5 h by using a continuous rolling mill, the final rolling temperature is 780 ℃, and the cumulative deformation amount is controlled to be 99.0%, so that the titanium-zirconium-based alloy rod is obtained.

[0063] (5) The titanium-zirconium-based alloy rod is subjected to drawing at room temperature by using a disc drawing machine, the drawing speed is 2.0 m / min, and the cumulative deformation amount is 65%.

[0064] (6) The drawn titanium-zirconium-based alloy wire is subjected to sizing by using a slide block straightening machine, and the wire length is controlled to be 2800 mm.

[0065] (7) The sized wire is subjected to rapid electric heating by using electric straightening, the hot straightening temperature is 650 ℃, and the straightening time is 10 s. The size of the nanoscale eutectoid compound after air cooling is in the range of 25-200 nm, and the volume fraction is 14%.

[0066] (8) The hot straightened wire is subjected to solid solution treatment by using a bench-type resistance furnace, the solid solution temperature is 650 ℃, the holding time is 1.0 h, and the wire is immediately water quenched after being taken out of the furnace. The size of the sub-micron eutectoid compound after water quenching is in the range of 250-600 nm, and the volume fraction is 9%.

[0067] (9) The titanium-zirconium-based alloy wire after the solid solution treatment is subjected to centerless grinding, and the centerless grinding amount is 0.02 mm each time, and then the surface of the titanium-zirconium-based alloy wire is subjected to polishing treatment, so that the finished product titanium-zirconium-based alloy wire with a diameter of 5.0 mm is obtained.

[0068] Comparative Example 1 Comparative Example 1 and Example 1 differ in that: in step (7), the rapid electric heating temperature is 550℃, heating at 550℃ for 30s, and then in step (8), the solution temperature is 850℃, holding for 0.5h, air cooling; the rest of the operations are the same, and finally Φ5.0mm of finished titanium-zirconium-based alloy wire is obtained.

[0069] Comparative Example 2 Comparative Example 2 and Example 1 differ in that: no rapid electric heating treatment and solution treatment are used, after completing step (6), step (9) is directly performed, and the rest of the operations are the same, and finally Φ5.0mm of finished titanium-zirconium-based alloy wire is obtained.

[0070] Comparative Example 3 Comparative Example 3 and Example 1 differ in that: no eutectoid β-stabilizing element is used in the titanium-zirconium-based alloy raw material, i.e., the chemical composition and mass percentage of the titanium-zirconium-based alloy ingot are: Zr 15.0%; the balance is Ti and unavoidable impurities; the rest of the operations are the same as in Example 1, and finally Φ5.0mm of finished titanium-zirconium-based alloy wire is obtained.

[0071] Experimental Example 1. The finished titanium-zirconium-based alloy wire prepared in Examples 1-3 is detected, and the metallographic structure diagrams thereof are shown in Figures 1-3 respectively. As can be seen from Figures 1-3 , there are micron-sized eutectoid compounds and nanoscale eutectoid β element compounds at the α / β phase interface. The precipitation of such multi-scale eutectoid β element compounds combined with α phase and β phase will produce significant heterogeneous structure strength effect, which will improve the strength of the alloy while endowing the alloy with sustained work hardening ability and plastic deformation ability, and successfully obtain titanium-zirconium-based alloy wire with high strength and high plasticity.

[0072] 2. The mechanical properties of the finished titanium-zirconium-based alloy wire of Examples 1-3 and Comparative Examples 1-3 are detected respectively. The detection method is carried out according to the provisions of GB / T 13810-2017 "Titanium and Titanium-Zirconium-Based Alloy Processing Materials for Surgical Implants". The mechanical property detection results of the finished titanium-zirconium-based alloy wire of Examples 1-3 and Comparative Examples 1-3 are shown in Table 1.

[0073] Table 1 Mechanical property detection results of finished titanium-zirconium-based alloy wire

[0074] From the above experimental results, it can be seen that the titanium-zirconium-based alloy wire with stable mechanical properties of Rm of 866-892 MPa, Rp0.2 of 749-788 MPa, and A of 17.5-19.0% can be prepared by using the preparation method defined in the application, which fully meets and is higher than the mechanical property requirements in the standard GB / T 13810-2017. The finished titanium-zirconium-based alloy wire prepared by the application has excellent plasticity and strength.

[0075] Comparing Comparative Examples 1-3 and Comparative Example 1, it can be seen that the tensile strength, yield strength, and elongation of the finished titanium-zirconium-based alloy wire prepared in Comparative Example 1 are all less than those of Examples 1-3. Therefore, it can be seen that, by precipitating nanoscale compounds rich in eutectoid β elements in the rapid electric heating process, the application improves the strength without sacrificing the plasticity of the alloy. Subsequent solid solution treatment precipitates submicron-scale compounds rich in eutectoid β elements at the α / β phase interface. The precipitation of such multi-scale compounds rich in eutectoid β elements in combination with the α phase and the β phase produces a significant heterogeneous structure strength effect, which improves the strength of the alloy while imparting the alloy with sustained work hardening capacity and plastic deformation capacity.

[0076] Comparing Comparative Examples 1-3 and Comparative Example 2, it can be seen that the tensile strength, yield strength, and elongation of the finished titanium-zirconium-based alloy wire prepared in Comparative Example 2 are all less than those of Examples 1-3. Therefore, it can be seen that the combination of the rapid heating treatment and the short-time solid solution treatment in the application reduces residual stress and changes the microstructure, precipitates submicron-scale and nanoscale compounds rich in eutectoid β elements, improves the strength while improving the plasticity, and is suitable for industrial mass production.

[0077] Therefore, the preparation method defined in the application can produce high-strength and high-plasticity titanium-zirconium-based alloy wire for export cavities, provide qualified raw materials for dental implant products, and improve the market rate of domestic implants.

[0078] The above only describes the preferred embodiments of the application and is not intended to limit the application. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the application shall be included in the protection scope of the application.

Claims

1. A method of producing a high strength ductility matched titanium zirconium based alloy wire enriched in a multi-scale eutectoid compound, characterized in that, The method comprises the following steps: (1) preparing a titanium-zirconium-based alloy raw material containing a eutectoid β stabilizing element, and preparing a titanium-zirconium-based alloy ingot through vacuum consumable melting; (2) β phase region open forging: in the β phase temperature T β +200℃ after holding, using fast forging machine forging; (3) β phase region one-time rolling: after holding at T β +100 ℃, rolling with cross rolling mill; (4) Two fire rolling in α+β phase region: in T β After keeping at 40℃ for 0.5h, the titanium-zirconium based alloy rod was obtained by continuous rolling mill. (5) drawing: drawing the titanium-zirconium-based alloy rod to obtain a titanium-zirconium-based alloy wire through a disc drawing machine; (6) performing length processing on the drawn titanium-zirconium-based alloy wire through a slide block straightening machine; (7) rapid heating treatment: performing rapid electric heating treatment on the length-processed titanium-zirconium-based alloy wire through an electric straightening machine, and then air cooling, wherein the heating temperature is 600-800℃; (8) solid solution treatment: performing solid solution treatment on the titanium-zirconium-based alloy wire after the rapid electric heating treatment, and controlling the temperature at 650-800℃; (9) performing centerless grinding and polishing on the titanium-zirconium-based alloy wire after the solid solution treatment to obtain the high strength and plasticity matching titanium-zirconium-based alloy wire.

2. The production method according to claim 1, characterized by, In step (1), the mass percentage content of each element in the titanium-zirconium-based alloy ingot is: Zr: 5-20%, eutectoid β stabilizing element: 0.5-10%, and the balance of Ti and unavoidable impurities. The eutectoid β stabilizing element is one of Fe, Mn, Cr, Ni and Cu.

3. The preparation method according to claim 1, characterized in that, In step (1), sponge titanium, sponge zirconium and the eutectoid β stabilizing element are used as raw materials, and the titanium-zirconium-based alloy ingot is obtained through three times of melting; In step (5), the drawing speed is 1-2 m / min, and the cumulative deformation is 40-70%; in step (6), the length of the wire after length processing is 2500-3000 mm; 4. The preparation method according to claim 1, characterized in that, The heating temperature before the open-die forging in step (2) is T β +200℃, holding for 3.5-5h, the forging temperature range is 800-1000℃, the open-die forging needs to be heated for 1-2 times in the process, and the total deformation of the open-die forging is 60%-80%.

5. The preparation method according to claim 1, characterized in that, In one pass rolling in step (3), the rolling temperature is T β +100℃, holding for 2-5h, and the cumulative deformation is not less than 75%-85%.

6. The method of claim 1, wherein, In the second rolling in step (4), the pre-rolling temperature is T β -40℃, and the final rolling temperature is 700-850℃, with a cumulative deformation of not less than 99%.

7. The preparation method according to claim 1, characterized in that, Preferably, in step (6), the slide block straightening machine is used to process the coil wire according to a length of 2800 mm. In step (7), the rapid electric heating time is 5-20 s, and the temperature rising rate is ≥30℃ / s; 8. The method of claim 1, wherein, After air cooling, the particle size of the nanoscale eutectoid compound is 20-200 nm, and the volume fraction is 10-16%. In step (8), the holding time of the solid solution treatment is 0.5-2 h, and the rapid cooling is water quenching, and the cooling rate is ≥100℃ / s; 9. The method of claim 1, wherein, After water quenching, the particle size of the submicron eutectoid compound is 200-600 nm, and the volume fraction is 5-10%; Preferably, in step (9), the centerless grinding amount is less than 0.02 mm each time. The titanium-zirconium-based alloy wire prepared by the preparation method in any one of claims 1-9 has a tensile strength of ≥850 MPa and an elongation of ≥15%.

10. A high strength to ductility matched titanium zirconium based alloy wire enriched in a multi-scale eutectoid compound, characterized in that, ​

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