A TB5 titanium alloy wire and a cold drawing preparation method thereof

Abstract

This invention belongs to the field of alloy preparation technology, and specifically relates to a TB5 titanium alloy wire and its cold drawing preparation method. Firstly, the forging and rolling of the TB5 titanium alloy involves selecting a large deformation amount and a low processing temperature, effectively ensuring that the coarse microstructure is broken down to a certain extent, improving the internal structure and increasing plasticity. Then, the surface oxide scale of the TB5 titanium alloy wire is removed to avoid introducing oxygen, hydrogen, nitrogen, and carbon elements. Next, online solution treatment is used to regulate the microstructure, improving the cold working performance and microstructure uniformity of the wire. Finally, roll drawing is performed to cold work the wire to reduce its diameter, effectively avoiding problems such as film adhesion and surface scratches, extending the service life of the drawing die. Simultaneously, the TB5 titanium alloy wire exhibits good grain size and microstructure uniformity, meeting the requirements for use. The final TB5 titanium alloy wire is delivered directly in a bright state and can be used for subsequent processing.

Description

Technical Field

[0001] This invention belongs to the field of alloy preparation technology, and specifically relates to a TB5 titanium alloy wire and its cold drawing preparation method. Background Technology

[0002] TB5 (Ti-15V-3Cr-3Sn-3Al) is a β-type titanium alloy characterized by low density, high specific strength, strong corrosion resistance, excellent cold-working properties, and superelasticity. Therefore, it is mainly used in medical, electronic, and eyeglass frame industries. With the rapid development of the titanium alloy industry and the increasing demands for advanced titanium alloy wires, TB5 titanium alloy wires have been widely used in the market in recent years. However, there are certain differences in batch stability and microstructure uniformity among different TB5 titanium alloy wire products.

[0003] The traditional wire drawing process for TB5 titanium alloy wire is: hot drawing with a fixed die, heat treatment, pickling, and polishing. This process is mostly used to deliver wire rods and machined surfaces. The problems with the TB5 wire produced by the above hot drawing process are: (1) the fixed die drawing speed is slow, the single-pass diameter reduction is small, the processing steps are long, and the production efficiency is low; (2) the heating temperature during hot drawing is 700℃~800℃, which easily causes the wire to absorb harmful elements such as nitrogen, hydrogen, and oxygen from the air under the heated state, reducing the consistency of material properties; (3) there is a very large sliding friction between the fixed die and the wire during drawing, which easily leads to a large increase in the dimensional tolerance of the wire and scratches on the wire surface, forming a continuous quality defect; (4) after the wire drawing is completed, electrolytic polishing or pickling must be used to remove the graphite or phosphoric acid lubricant on the surface of the wire, which will cause high energy consumption and high pollution in the wire preparation. Summary of the Invention

[0004] To address the aforementioned problems, this invention proposes a TB5 titanium alloy wire and its cold drawing preparation method. First, large deformation and low processing temperatures are selected for the forging and rolling of the TB5 titanium alloy, effectively ensuring that the coarse microstructure is broken down to a certain extent, improving the internal structure and increasing plasticity. Then, the surface oxide scale of the TB5 titanium alloy wire is removed to avoid introducing oxygen, hydrogen, nitrogen, and carbon elements. Next, online solution treatment is used to regulate the microstructure, improving the cold working performance and microstructure uniformity of the wire. Finally, roll drawing is performed to cold work the wire to reduce its diameter, effectively avoiding problems such as film adhesion and surface scratches, extending the service life of the drawing die. Simultaneously, the TB5 titanium alloy wire exhibits good grain size and microstructure uniformity, meeting the application requirements. The final TB5 titanium alloy wire is delivered directly in a bright state for subsequent processing.

[0005] The specific technical solution is as follows:

[0006] The beneficial effects of this invention are:

[0007] This invention employs a roller die drawing method to prepare TB5 titanium alloy wire. It transforms most of the sliding friction between the material and the die hole during fixed die drawing into rolling friction of the bearing, thereby significantly reducing tensile friction and making the drawing process more labor-saving and efficient. It also offers advantages such as high-speed diameter reduction, high total compression ratio, high dimensional accuracy, and good microstructure uniformity, further improving the production efficiency and yield of TB5 titanium alloy wire, meeting the requirements of the civilian market for TB5 titanium alloy materials.

[0008] This invention employs large deformation and low processing temperatures during both forging and rolling processes, effectively ensuring a certain degree of breakage of coarse microstructure, improving internal structure, and enhancing plasticity. Furthermore, the entire wire process in this invention eliminates the need for pickling and electrolysis, making the production process green and environmentally friendly. No hydrogen, oxygen, or nitrogen is added during production, resulting in high component purity. The heat treatment process utilizes an online protective atmosphere furnace, which, compared to commonly used vacuum heat treatment furnaces, offers lower cost, higher energy efficiency, and is easier to operate and maintain.

[0009] This invention employs a roller drawing method to prepare TB5 titanium alloy wire. Compared with traditional hot drawing, the drawing speed is significantly increased, the production cycle is shortened, and there is no heating step involved, reducing production costs to 30% of the original cost. Simultaneously, it ensures the continuity and efficiency of subsequent wire processing. Furthermore, the wire product prepared by this invention exhibits excellent comprehensive properties. Cold working can refine the wire grain size to level 8; improve the cold deformation performance of TB5 wire, achieving 80% compression deformation without cracking; and ensure the consistency and stability of various mechanical properties of the wire, meeting customer requirements.

[0010] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures pointed out in the description, claims and drawings. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 A flowchart of a cold drawing method for preparing TB5 titanium alloy wire according to the present invention is shown;

[0013] Figure 2 The microstructure of TB5 titanium alloy wire with a diameter of Φ4.50mm is shown in an embodiment of the present invention.

[0014] Figure 3 The microstructure of TB5 titanium alloy wire with a diameter of Φ2.40mm is shown in an embodiment of the present invention.

[0015] Figure 4 The microstructure of a 1.20mm TB5 titanium alloy wire in an embodiment of the present invention is shown.

[0016] Figure 5 A microstructure diagram of a 4.50mm TB5 titanium alloy wire is shown in another embodiment of the present invention. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] This invention provides a method for cold drawing TB5 titanium alloy wire. The method involves sequentially forging and hot rolling the smelted ingot, followed by a roll drawing process to further improve the uniformity and stability of the wire, thereby obtaining TB5 titanium alloy wire. The main steps are as follows: Figure 1 As shown:

[0019] After removing the outer skin and risers, the TB5 ingot is forged in three stages to obtain a titanium billet.

[0020] The titanium billet is ground and then subjected to two-stage rolling to obtain coarse wire rod.

[0021] After rounding and peeling the coarse wire rod, the peeled coarse wire rod is subjected to online protective atmosphere annealing heat treatment to obtain wire rod.

[0022] The wire rod is drawn to the finished wire size using a roller drawing method, wherein the wire size is Φ1.20mm-Φ4.50mm;

[0023] The finished TB5 titanium alloy wire is obtained by ultrasonic cleaning, online protective atmosphere solution treatment and aging treatment of the wire.

[0024] The specific steps are as follows: Follow the steps in S1-S7.

[0025] S1: After removing the outer skin and riser from the TB5 ingot, a titanium billet is obtained; the forging process uses a three-fire forging method to obtain coarse wire rod;

[0026] The first forging process uses a three-upsetting and three-drawing method, with an initial forging temperature of 1100~1150℃, a holding time of 3 hours, and a final forging temperature of >800℃. The deformation during upsetting and drawing is 65~70%.

[0027] The second forging process uses a two-upsetting and two-drawing method, with an initial forging temperature of 1050~1100℃, a holding time of 3 hours, and a final forging temperature >700℃. The deformation amount during upsetting and drawing is 60~65%.

[0028] The third forging process uses a one-upsetting and one-drawing method, with an initial forging temperature of 950~1050℃, a holding time of 3 hours, and a final forging temperature of >600℃. The deformation amount of upsetting and drawing is 60~65%.

[0029] S2: The surface of the forged titanium billet in step S1 is polished to a metallic luster and free of visible defects. It is then placed in a heating furnace for heating and rolled using a two-stage rolling process.

[0030] The first rolling temperature is 900~950℃, the holding time is 2h, the rolling speed is 3m / s, the final rolling size is Φ60mm, the rolling passes are 13, and the rolling deformation is 75%.

[0031] The second rolling temperature is 850~900℃, held for 2 hours, rolling speed is 2.5m / s, rolling passes are 8, the final rolling size is Φ16mm, and the rolling deformation is 90-92%.

[0032] S3: Before carrying out cold drawing, the rough wire rod obtained in step S2 needs to be rounded and peeled to obtain intermediate wire rod.

[0033] The rounding process involves using a hot drawing machine at 780℃ to remove ear-like defects from the material surface, resulting in a rounded size of Φ15.5mm. The peeling process uses a centerless grinding lathe to remove oxide scale and surface defects from the material surface, resulting in a peeled size of Φ14.5mm. The wire rod surface is then finished with a bright finish.

[0034] S4: The intermediate wire rod obtained in step S3 is subjected to annealing heat treatment to obtain wire rod; due to the work hardening and uneven structure of the obtained intermediate wire rod, it is necessary to perform annealing heat treatment to facilitate subsequent cold forging.

[0035] Specifically, the wire rod is heat-treated in an online protective atmosphere furnace at a temperature of 700℃~750℃, with a wire rod travel speed of 6~7m / min. The cooling method is water spray cooling, and the protective gas is 99.999% high-purity argon.

[0036] S5: The wire rod is drawn using a roller die to reduce the diameter of the Φ14.5mm wire rod to Φ1.20-4.50mm wire.

[0037] Before drawing with a roller die, a water-soluble lubricant needs to be evenly applied to the wire rod. During the drawing process, the deformation per pass is 20-25%, and the drawing speed is 1.6-2.5 m / s. After accumulating 4-5 drawing passes, an intermediate heat treatment annealing is performed, and then the wire rod is drawn to the finished size.

[0038] S6: The filament prepared in step S5 is subjected to ultrasonic cleaning to remove the lubricating oil from the filament surface. The heating temperature during ultrasonic cleaning is 50~60℃, the cleaning time is 2~3h, the ultrasonic frequency is 3~5kHz, and the cleaning medium is water-based cleaning agent.

[0039] S7: The cleaned filaments from step S6 are subjected to solution treatment and aging treatment to obtain finished filaments with the best comprehensive performance.

[0040] Solution treatment is performed in an online protective atmosphere heat treatment furnace at a temperature of 730℃~780℃, with a wire travel speed of 4~6m / min. Cooling is achieved through water spraying, and the protective gas is 99.999% high-purity argon. Aging treatment is performed in a vacuum heat treatment furnace at a heating temperature of 500~550℃, a holding time of 6~8 hours, and furnace cooling.

[0041] To more clearly illustrate the specific operation process of the above method and the morphology of the microstructure of the prepared TB5 titanium alloy wire, the following detailed description is provided in conjunction with specific embodiments.

[0042] Example 1: TB5 titanium alloy wire with a diameter of 4.50 mm was prepared using TB5 ingots with a diameter of 300 mm and uniform composition.

[0043] Step 1: Use 300mm TB5 ingots with uniform composition and a 2000t hydraulic press for forging and blanking.

[0044] The first forging process involves an initial forging temperature of 1130℃, a holding time of 3 hours, and a final forging temperature exceeding 800℃, resulting in an upsetting and elongation deformation of 68%. The second forging process involves an initial forging temperature of 1080℃, a holding time of 3 hours, and a final forging temperature exceeding 700℃, resulting in an upsetting and elongation deformation of 65%. The third forging process involves an initial forging temperature of 1000℃, a holding time of 3 hours, and a final forging temperature exceeding 600℃, resulting in an upsetting and elongation deformation of 62%.

[0045] Step 2: After surface treatment, the titanium billet forged in Step 1 is rolled using a reciprocating rolling mill.

[0046] The first rolling pass was at a temperature of 930℃, held for 2 hours, rolled at a speed of 2 m / s, with a final rolled size of Φ60 mm, 13 rolling passes, and a rolling deformation of 75%. The second rolling pass was at a temperature of 880℃, held for 2 hours, rolled at a speed of 2.5 m / s, 8 rolling passes, with a final rolled size of Φ16 mm and a rolling deformation of 92%.

[0047] Step 3: Perform a rounding and peeling process on the wire rod from Step 2. The rounded size is Φ14.5mm~15.5mm, and the peeled size is Φ14.5mm. The surface of the wire rod is smooth.

[0048] Step 4: The intermediate filament material obtained in Step 3 is subjected to annealing heat treatment.

[0049] The wire rod is heat-treated in an online protective atmosphere furnace at a temperature of 750℃. The wire travel speed is 7m / min. The cooling method is water spray cooling, and the protective gas is 99.999% high-purity argon.

[0050] Step 5: Apply a water-soluble lubricant evenly to the annealed wire from Step 4, and then perform roller drawing.

[0051] The Φ14.5mm wire rod is reduced to Φ4.50mm in 13 passes using a continuous drawing roller die. Each time the wire rod is reduced in diameter, a step 4 annealing heat treatment is performed.

[0052] Step 6: The TB5 titanium alloy wire drawn to Φ4.50mm in Step 5 is ultrasonically cleaned.

[0053] The ultrasonic cleaning process involves heating at 50°C, cleaning for 2 hours, using an ultrasonic frequency of 3kHz, and employing a water-based cleaning agent as the cleaning medium.

[0054] Step 7: Perform solution aging treatment on the cleaned wire from Step 6. Use an online protective atmosphere heat treatment furnace. The heat treatment temperature should be 780℃, the wire travel speed should be 4m / min, and the cooling method should be spray water cooling. The protective gas is 99.999% high-purity argon. The aging treatment uses a vacuum heat treatment furnace. The heating temperature is 550℃, the holding time is 8 hours, and the cooling method is furnace cooling.

[0055] The microstructure of the Φ4.50mm solution-treated and aged TB5 wire prepared in this embodiment was observed, and the microstructure results are as follows: Figure 2As shown, its internal structure is uniform and stable, and the grains of the filament are uniform. The mechanical properties of the prepared Φ4.50mm solution-treated and aged TB5 filament were tested. Six test points were selected on the prepared TB5 filament (the six test points were selected separately), and the tensile strength, yield strength, elongation and reduction of area were tested respectively. The results are shown in Table 1. It can be seen from Table 1 that the various mechanical properties of the filament are consistent and stable.

[0056] Table 1. Test results of mechanical properties of TB5 wire in solution-treated and aged state with a diameter of 4.50mm.

[0057]

[0058] Example 2: TB5 titanium alloy wire with a diameter of 2.40 mm was prepared using TB5 ingots with a diameter of 350 mm and uniform composition.

[0059] Step 1: Using TB5 ingots with uniform composition and a Φ350mm specification, forging is performed using a 2000t hydraulic press. First forging: initial forging temperature 1100℃, holding time 3 hours, final forging temperature >800℃, upsetting and elongation deformation 68%. Second forging: initial forging temperature 1050℃, holding time 3 hours, final forging temperature >700℃, upsetting and elongation deformation 66%. Third forging: initial forging temperature 970℃, holding time 3 hours, final forging temperature >600℃, upsetting and elongation deformation 63%.

[0060] Step 2: After surface treatment, the titanium billet forged in Step 1 is rolled using a reciprocating rolling mill. The first rolling pass is at a temperature of 920℃, held for 2 hours, with a rolling speed of 2 m / s, a final rolled size of Φ60 mm, 13 rolling passes, and a rolling deformation of 75%. The second rolling pass is at a temperature of 860℃, held for 2 hours, with a rolling speed of 2.5 m / s, 8 rolling passes, a final rolled size of Φ16 mm, and a rolling deformation of 92%.

[0061] Step 3: Perform a rounding and peeling process on the wire rod from Step 2. The size after peeling is Φ14.5mm, and the surface of the wire rod is smooth.

[0062] Step 4: Anneal the intermediate wire obtained in Step 3. The wire rod is heat-treated in an online protective atmosphere furnace at a temperature of 730℃. The wire travel speed is 6.5 m / min, and the cooling method is water spray cooling. The protective gas is 99.999% high-purity argon.

[0063] Step 5: Apply a water-soluble lubricant evenly to the annealed wire material from Step 4, and then perform roller drawing. Use a continuous-drawing type roller drawing machine to reduce the diameter of the Φ14.5mm wire rod to Φ2.40mm in 20 passes, with the heat treatment annealing from Step 4 performed once every 4 passes of diameter reduction.

[0064] Step 6: The TB5 titanium alloy wire drawn to Φ2.40mm in Step 5 is then ultrasonically cleaned. The ultrasonic cleaning temperature is 55℃, the cleaning time is 2.5h, the ultrasonic frequency is 4kHz, and the cleaning medium is water-based cleaning agent.

[0065] Step 7: Perform solution aging treatment on the cleaned wire from Step 6. Use an online protective atmosphere heat treatment furnace at a temperature of 730℃, a wire travel speed of 4.5 m / min, and water spray cooling. The protective gas is 99.999% high-purity argon. The aging treatment uses a vacuum heat treatment furnace at a heating temperature of 530℃, a holding time of 6 hours, and furnace cooling.

[0066] The microstructure of the Φ2.40mm solution-treated and aged TB5 wire prepared in this embodiment was observed, and the microstructure results are as follows: Figure 3 As shown, its internal structure is uniform and stable, and the grains of the filament are uniform. Mechanical properties of the prepared Φ2.40mm solution-treated TB5 filament were tested. Six test points were selected on the prepared TB5 filament (the six test points were selected separately), and tensile strength, yield strength, elongation, and reduction of area were tested respectively. The results are shown in Table 2. Table 2 shows that the various mechanical properties of the filament are consistent and stable.

[0067] Table 2. Test results of mechanical properties of TB5 wire with a diameter of Φ2.40mm

[0068]

[0069] Example 3: 1.20mm TB5 titanium alloy wire was prepared using 400mm TB5 ingots with uniform composition.

[0070] Step 1: Using TB14 ingots with uniform composition and Φ400mm specifications, forging is performed using a 2000t hydraulic press. The first forging temperature is 1100℃, held for 3 hours, and the final forging temperature is >800℃, with an upsetting and elongation deformation of 66%. The second forging temperature is 1050℃, held for 3 hours, and the final forging temperature is >700℃, with an upsetting and elongation deformation of 64%. The third forging temperature is 950℃, held for 3 hours, and the final forging temperature is >600℃, with an upsetting and elongation deformation of 62%.

[0071] Step 2: After surface treatment, the titanium billet forged in Step 1 is rolled using a reciprocating rolling mill. The first rolling pass is at a temperature of 900℃, held for 2 hours, with a rolling speed of 3 m / s, a final rolled size of Φ60 mm, 13 rolling passes, and a rolling deformation of 75%. The second rolling pass is at a temperature of 850℃, held for 2 hours, with 10 rolling passes, a rolling speed of 2.5 m / s, a final rolled size of Φ16 mm, and a rolling deformation of 90%.

[0072] Step 3: Perform a rounding and peeling process on the wire rod from Step 2. The size after peeling is Φ14.5mm, and the surface of the wire rod is smooth.

[0073] Step 4: The intermediate wire obtained in Step 3 is subjected to annealing heat treatment. The wire rod is processed in an online protective atmosphere heat treatment furnace. The heat treatment temperature should be 700℃, the wire travel speed should be 6m / min, the cooling method is spray water cooling, and the protective gas is 99.999% high-purity argon.

[0074] Step 5: Apply a water-soluble lubricant evenly to the annealed wire from Step 4, and then perform roller drawing. Use a continuous-drawing roller drawing machine to reduce the diameter of the Φ14.5mm wire rod to Φ1.20mm in 26 passes, with the heat treatment annealing from Step 4 performed once every 4 passes of diameter reduction.

[0075] Step 6: The TB5 titanium alloy wire drawn to Φ1.20mm in Step 5 is then ultrasonically cleaned. The ultrasonic cleaning temperature is 60℃, the cleaning time is 3 hours, the ultrasonic frequency is 5kHz, and the cleaning medium is water-based cleaning agent.

[0076] Step 7: Perform solution treatment on the cleaned filaments from Step 6. Use an online protective atmosphere heat treatment furnace at a temperature of 700℃, a filament travel speed of 4m / min, and water spray cooling. The protective gas is 99.999% high-purity argon. For aging treatment, use a vacuum heat treatment furnace at a heating temperature of 500℃, a holding time of 4 hours, and furnace cooling.

[0077] The microstructure of the Φ1.20mm solution-treated and aged TB5 wire prepared in this embodiment was observed, and the microstructure results are as follows: Figure 4 As shown, its internal structure is uniform and stable, and the grains of the filament are uniform. Mechanical properties of the prepared Φ1.20mm solution-treated and aged TB5 filament were tested. Six test points were selected on the prepared TB5 filament (the six test points were selected separately), and tensile strength, yield strength, elongation, and reduction of area were tested respectively. The results are shown in Table 3. Table 3 shows that the various mechanical properties of the filament are consistent and stable.

[0078] Table 3. Mechanical property test results of TB5 with a diameter of Φ1.20mm.

[0079]

[0080] As can be seen from the above embodiments, the TB5 filament prepared by the present invention has a stable internal structure and excellent mechanical properties.

[0081] Comparative Example 1: 4.50mm TB5 titanium alloy wire was prepared by hot drawing. The preparation process was the same as in Example 1, except that the roll drawing in step 5 was replaced by hot drawing.

[0082] Step 1: Use 300mm TB5 ingots with uniform composition and a 2000t hydraulic press for forging and blanking.

[0083] The first forging process involves an initial forging temperature of 1130℃, a holding time of 3 hours, and a final forging temperature exceeding 800℃, resulting in an upsetting and elongation deformation of 68%. The second forging process involves an initial forging temperature of 1080℃, a holding time of 3 hours, and a final forging temperature exceeding 700℃, resulting in an upsetting and elongation deformation of 65%. The third forging process involves an initial forging temperature of 1000℃, a holding time of 3 hours, and a final forging temperature exceeding 600℃, resulting in an upsetting and elongation deformation of 62%.

[0084] Step 2: After surface treatment, the titanium billet forged in Step 1 is rolled using a reciprocating rolling mill.

[0085] The first rolling pass was at a temperature of 930℃, held for 2 hours, rolled at a speed of 2 m / s, with a final rolled size of Φ60 mm, 13 rolling passes, and a rolling deformation of 75%. The second rolling pass was at a temperature of 880℃, held for 2 hours, rolled at a speed of 2.5 m / s, 8 rolling passes, with a final rolled size of Φ16 mm and a rolling deformation of 92%.

[0086] Step 3: Perform a rounding and peeling process on the wire rod from Step 2. The size after peeling is Φ14.5mm, and the surface of the wire rod is smooth.

[0087] Step 4: The intermediate wire obtained in Step 3 is reduced in diameter by hot drawing at a heating temperature of 820℃ and a drawing speed of 10m / min. Graphite emulsion is used as the drawing lubricant. The diameter is reduced to Φ4.50mm in 13 passes.

[0088] Step 5: The TB5 titanium alloy wire drawn to Φ4.50mm in Step 4 is mechanically polished.

[0089] The polishing speed during mechanical polishing is 4 m / min, and the polishing is done with silica abrasive belts with mesh sizes of 180, 320, and 400.

[0090] Step 6: Perform solution aging treatment on the polished wire from Step 5. Use an online protective atmosphere heat treatment furnace. The heat treatment temperature should be 780℃, the wire travel speed should be 4m / min, and the cooling method should be spray water cooling. The protective gas is 99.999% high-purity argon. The aging treatment uses a vacuum heat treatment furnace. The heating temperature is 550℃, the holding time is 8 hours, and the cooling method is furnace cooling.

[0091] The microstructure of the final prepared Φ4.50mm solution-treated and aged TB5 wire was observed, and the microstructure results are as follows: Figure 5 As shown, the microstructure of the wire prepared by hot drawing is coarse, with a grain size of about 100 μm.

[0092] Mechanical properties of the prepared 4.50mm TB5 wire under solution treatment and aging were tested. Six test points were selected on the prepared TB5 wire (the six test points were selected separately) to test tensile strength, yield strength, elongation and reduction of area. The results are shown in Table 4. It can be seen from Table 4 that the tensile strength and elongation of the wire prepared by hot drawing are reduced, and the comprehensive mechanical properties of the wire are worse.

[0093] Table 4. Mechanical property test results of TB5 with a diameter of Φ4.50mm.

[0094]

[0095] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for cold drawing TB5 titanium alloy wire, characterized in that, The method includes the following steps: The pretreated TB5 ingot is forged in three stages to obtain a titanium billet; the forging process includes a first forging, a second forging, and a third forging; wherein the first forging adopts a three-upsetting and three-drawing method, the second forging adopts a two-upsetting and two-drawing method, and the third forging adopts a one-upsetting and one-drawing method. The titanium billet is ground and then subjected to two rolling processes to obtain coarse wire rod; the first rolling process has 13 passes and a rolling deformation of 75%, and the second rolling process has 8 passes and a rolling deformation of 90-92%. After rounding and peeling the coarse wire rod in sequence, the peeled coarse wire rod is annealed in an online protective atmosphere heat treatment furnace to obtain wire rod. The annealing temperature is 700℃~750℃. The wire rod is drawn to the finished size using a roller drawing method. Specifically, a water-soluble lubricant is applied to the annealed wire rod. During the drawing process, the deformation per pass is 20-25%, and the drawing speed is 1.6-2.5 m / s. After accumulating 4-5 drawing passes, an intermediate heat treatment annealing is performed, and then the wire is drawn to the finished size. The specifications of the wire are Φ1.20mm-Φ4.50mm. The wire is then subjected to ultrasonic cleaning, online protective atmosphere solution treatment, and aging treatment to obtain the finished TB5 titanium alloy wire. The online protective atmosphere solution treatment is performed in an online protective atmosphere heat treatment furnace at a temperature of 730℃-780℃.

2. The method for preparing TB5 titanium alloy wire by cold drawing according to claim 1, characterized in that, The pretreatment includes peeling and removing risers from the TB5 ingot.

3. The method for preparing TB5 titanium alloy wire by cold drawing according to claim 1, characterized in that, The forging conditions for the first forging are: initial forging temperature of 1100~1150℃, holding temperature for 3 hours, final forging temperature greater than 800℃, and upsetting and drawing deformation of 65~70%; The forging conditions for the second forging are: initial forging temperature of 1050~1100℃, holding temperature for 3 hours, final forging temperature greater than 700℃, and upsetting and drawing deformation of 60~65%; The forging conditions for the third forging are: initial forging temperature of 950~1050℃, holding temperature for 3 hours, final forging temperature greater than 600℃, and upsetting and drawing deformation of 60~65%.

4. The method for preparing TB5 titanium alloy wire by cold drawing according to claim 1, characterized in that, The specific process of grinding the titanium blank is as follows: The surface of the titanium billet is polished to a metallic luster and free of defects visible to the naked eye, and then placed in a heating furnace for heating. The rolling process is a two-stage rolling process. The rolling process employs a two-stage billet rolling method, specifically: The first rolling temperature is 900~950℃, the holding time is 2h, the rolling speed is 3m / s, and the final rolling size is Φ60mm; The second rolling temperature is 850~900℃, the holding time is 2h, the rolling speed is 2.5m / s, and the final rolled size is Φ16mm.

5. The method for preparing TB5 titanium alloy wire by cold drawing according to claim 1, characterized in that, The rounding of the coarse wire rod is specifically performed by hot drawing at 780°C using a hot drawing machine to remove ear defects on the material surface. The size of the rounded wire rod is Φ15.5mm. The process of peeling the coarse wire rod involves using a centerless grinder to remove the oxide scale and surface defects from the rounded wire rod. The size of the stripped wire rod is Φ14.5mm.

6. The method for preparing TB5 titanium alloy wire by cold drawing according to claim 1, characterized in that, The online protective atmosphere annealing heat treatment of the rough wire rod after peeling is specifically as follows: The coarse wire rod travels at a speed of 6-7 m / min in the online protective atmosphere heat treatment furnace and is cooled by spray water cooling. The protective gas is 99.999% high-purity argon.

7. The method for preparing TB5 titanium alloy wire by cold drawing according to claim 1, characterized in that, The ultrasonic cleaning of the filament is specifically performed as follows: the heating temperature for ultrasonic cleaning is 50~60℃, the cleaning time is 2~3h, the ultrasonic frequency is 3~5kHz, and the cleaning medium is water-based cleaning agent. The online protective atmosphere solution treatment is as follows: the wire travels at a speed of 4~6m / min in the online protective atmosphere heat treatment furnace, is cooled by spray water cooling, and the protective gas is 99.999% high-purity argon. The aging process is performed in a vacuum heat treatment furnace, with a heating temperature of 500~550℃, a holding time of 6~8h, and a furnace cooling method.

8. A TB5 titanium alloy wire, characterized in that, Prepared using the cold drawing method according to any one of claims 1-7.

9. The TB5 titanium alloy wire according to claim 8, characterized in that, The specifications of the TB5 titanium alloy wire are Φ1.20mm-Φ4.50mm.

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