Method for preparing ultrafine titanium wire by using ethanol-based electrolyte at low cost

Abstract

The application discloses a method for preparing superfine titanium wire by using ethanol-based electrolyte at low cost, and belongs to the technical field of metal material surface treatment, and comprises the following steps: one, pickling of pure titanium wire; two, preparation of electrolyte; three, applying constant voltage electrolytic polishing to reduce the diameter of the pure titanium wire by taking a columnar metal electrode as a cathode and the pickled pure titanium wire as an anode; four, preparation of new electrolyte by adding corrosion inhibitor into the electrolyte; and five, applying gradient constant current deep polishing to the titanium wire after diameter reduction for secondary diameter reduction by taking a columnar metal electrode as a counter electrode, taking the titanium wire after diameter reduction as a working electrode, and taking a saturated calomel electrode as a reference electrode. The application only uses a conventional direct current power supply and an electrochemical workstation, is simple to operate, significantly reduces equipment cost and energy consumption, avoids a strong acid system, has the advantages of environmental friendliness and high practicability, and the prepared superfine titanium wire has a smooth surface, uniform size, low roughness and good electrochemical performance, and is suitable for high value-added fields such as medical stents and precision sensors.

Description

Technical Field

[0001] This invention belongs to the field of metal material surface treatment technology, specifically relating to a method for preparing ultrafine titanium wires with ethanol-based electrolyte at low cost. Background Technology

[0002] Titanium and its alloys are widely used in aerospace, chemical, and medical fields due to their high specific strength, excellent corrosion resistance, and good biocompatibility.

[0003] Titanium wire, due to its slender structure, is used to manufacture filters, precision sensing elements, medical stents, and functional electrode materials. However, titanium wire often suffers from defects such as scratches and excessive surface roughness during the manufacturing process, which directly affect its performance.

[0004] Electropolishing, a surface treatment method primarily based on electrochemical reactions, can achieve efficient, uniform, and controllable surface finishing of metals, offering unique advantages in precision manufacturing. However, research on electropolishing of titanium wires with diameters of only 0.5 mm or even smaller is relatively limited, especially the process of stably reducing the diameter of titanium wires from below 0.1 mm to 0.05 mm while maintaining good surface quality, which is rarely reported.

[0005] Currently, the preparation of ultrafine titanium wires with a diameter of 0.05 mm typically relies on harsh conditions such as processing in a strong acid system at extremely low temperatures, drawing processes, pulsed power electrolysis, or laser processing. These existing technologies have the following drawbacks: first, the equipment is expensive and the processes are complex, resulting in extremely high production costs; second, the wire breakage rate is high during processing, and the product yield is low; and third, the use of strong acid systems often leads to significant environmental pollution and poor operational safety.

[0006] Therefore, developing a low-cost, conventional, and environmentally friendly method for preparing ultrafine titanium wires has become a pressing technical challenge in this field. Summary of the Invention

[0007] To address the problems mentioned in the background section, this invention provides a low-cost method for preparing ultrafine titanium wires using an ethanol-based electrolyte. This method eliminates the need for extreme low temperatures, pulsed power supplies, or laser equipment, requiring only a conventional DC power supply and an electrochemical workstation. It is simple to operate, significantly reduces equipment costs and energy consumption, and avoids strong acid systems, offering advantages such as environmental friendliness and high practicality. The prepared ultrafine titanium wires have smooth surfaces, uniform dimensions, low roughness, and excellent electrochemical performance, making them suitable for high-value-added applications such as medical stents and precision sensors.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a method for low-cost preparation of ultrafine titanium wires using an ethanol-based electrolyte, comprising the following steps: 1. Immerse the pure titanium wire in the pickling solution for pickling. After pickling, remove it and wash it with deionized water to remove the surface oxide layer. 2. Prepare an electrolyte by adding a chloride conductive salt to a mixed solution of organic alcohols; 3. Place the electrolyte prepared in step 2 into an electrolytic cell. Under the dual-electrode system of electrolytic polishing with DC power supply, use the columnar metal electrode in the electrolyte prepared in step 2 as the cathode and the pure titanium wire cleaned in step 1 and located inside the columnar metal electrode in the electrolyte prepared in step 2 as the anode. Apply constant voltage to electrolytic polish to reduce the diameter of the pure titanium wire cleaned in step 1. After the process is completed, take out the titanium wire and perform ultrasonic cleaning with anhydrous ethanol, washing with deionized water, drying with nitrogen, and oiling protection in sequence to obtain the titanium wire with reduced diameter. 4. Add the corrosion inhibitor to the electrolyte prepared in step 2 to prepare a new electrolyte; 5. Place the electrolyte prepared in step 4 into an electrolytic cell in an ice-water bath. Under the three-electrode constant current system of the electrochemical workstation, use the columnar metal electrode placed in the electrolyte prepared in step 4 as the counter electrode, and the titanium wire after diameter reduction in step 3 placed inside the columnar metal electrode in the electrolyte prepared in step 4 as the working electrode. Use a saturated calomel electrode as the reference electrode. Apply gradient constant current for deep polishing to perform secondary diameter reduction on the titanium wire after diameter reduction in step 3. After completion, take out the titanium wire after secondary diameter reduction and perform ultrasonic cleaning with anhydrous ethanol, washing with deionized water, drying with nitrogen, and oiling protection in sequence to obtain the ultrafine titanium wire after secondary diameter reduction.

[0009] Furthermore, in step one, the pure titanium wire is industrial titanium wire.

[0010] Furthermore, in step one, the pickling solution is a mixture of strong acid and deionized water, and the volume ratio of the strong acid to the deionized water is 3:7.

[0011] Furthermore, in step one, the strong acid is hydrofluoric acid.

[0012] Furthermore, in step two, the chloride conductive salt is a mixture of anhydrous aluminum chloride and anhydrous zinc chloride, and the mass ratio of the anhydrous aluminum chloride to the anhydrous zinc chloride is 1:2~4.

[0013] Furthermore, in step two, the organic alcohol mixture is a mixture of anhydrous ethanol and n-butanol, and the volume ratio of anhydrous ethanol to n-butanol is 2.1 to 9:1.

[0014] Furthermore, in step three, the metal electrode is one of a stainless steel electrode, a titanium electrode, or a platinum electrode.

[0015] Furthermore, in step three, the distance between the columnar metal electrode and the pure titanium wire cleaned in step one is 2-4 cm.

[0016] Furthermore, in step three, the specific steps for applying constant voltage electropolishing to reduce the diameter of the pure titanium wire cleaned in step one are as follows: apply a constant voltage of 40~60V, electropolish for 3~5 minutes, and reduce the diameter of the pure titanium wire cleaned in step one to 0.10~0.24mm.

[0017] Furthermore, in step three, the oil used for the protective coating is either rust-preventive oil or liquid paraffin.

[0018] Furthermore, in step four, the corrosion inhibitor is triethanolamine, and the amount of triethanolamine added is 0M~0.06M.

[0019] Furthermore, in step five, the temperature of the ice-water bath is 0~5℃.

[0020] Furthermore, in step five, the metal electrode is one of a stainless steel electrode, a titanium electrode, or a platinum electrode.

[0021] Furthermore, in step five, the distance between the columnar metal electrode and the titanium wire after diameter reduction in step three is 2-4 cm.

[0022] Furthermore, in step five, the specific steps for applying gradient constant current deep polishing to perform secondary diameter reduction on the titanium wire after diameter reduction in step three are as follows: first, apply 0.15~0.25A electrolysis for 0~6min, then apply 0.08~0.12A electrolysis for 0~4min, and finally apply 0.03~0.06A electrolysis for 0~15min to reduce the diameter of the titanium wire after diameter reduction in step three to <0.05mm.

[0023] Furthermore, in step five, the oil used for the protective coating is either rust-preventive oil or liquid paraffin.

[0024] Compared with the prior art, the beneficial effects of the present invention are: This invention first removes the surface oxide layer of pure titanium wire by acid washing. Then, in an electrolyte solution of ethanol-based anhydrous aluminum chloride and anhydrous zinc chloride mixed salt, using a columnar metal electrode as the cathode, constant voltage electropolishing is performed through a DC regulated power supply to rapidly reduce the diameter of the pure titanium wire to 0.1~0.24mm. Next, in an electrolyte solution of ethanol-based anhydrous aluminum chloride and anhydrous zinc chloride mixed salt with added corrosion inhibitor, placed in an ice-water bath at 0~5℃, a columnar metal electrode is used as the counter electrode, and a saturated calomel electrode is used as the reference electrode. Precision polishing is then performed by applying a gradient constant current through an electrochemical workstation. This method maintains the mirror-like surface quality and low breakage rate of pure titanium wire while stably reducing the diameter of pure titanium wire to below 0.05 mm. Compared with existing technologies, it does not require extreme low temperatures, pulsed power supplies, or laser equipment. It only uses conventional DC power supplies and electrochemical workstations, making it easy to operate, significantly reducing equipment costs and energy consumption. It also avoids strong acid systems, making it environmentally friendly and highly practical. The prepared ultrafine titanium wire has a smooth surface, uniform size, low roughness, and good electrochemical performance, making it suitable for high-value-added fields such as medical stents and precision sensors. Attached Figure Description

[0025] Figure 1 This is a simplified diagram of the device of the present invention; Figure 2 This is a SEM image of the titanium wire obtained after electrochemical fine polishing in Example 1 of the present invention; Figure 3 This is a SEM image of the titanium wire obtained after electrochemical fine polishing in Example 2 of the present invention. Figure 4 This is a SEM image of the titanium wire obtained after electrochemical fine polishing in Example 3 of the present invention; Figure 5 This is a SEM image of the titanium wire obtained after electrochemical fine polishing in Example 4 of the present invention. Figure 6 This is a SEM image of the titanium wire obtained after electrochemical fine polishing in Example 5 of the present invention; Figure 7 This is a SEM image of the titanium wire obtained after electrochemical fine polishing in Example 6 of the present invention; In the diagram: 1. Electrochemical workstation; 2. Columnar metal electrode cathode cylinder; 3. Titanium wire anode. Detailed Implementation

[0026] 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, and 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. Example 1

[0027] 1. Immerse a 0.5mm diameter TA1 industrial pure titanium wire in an acid pickling solution prepared with 30ml hydrofluoric acid and 70ml deionized water for 60s. After the surface oxide layer is completely peeled off and a uniform silver-white color is revealed, take it out and rinse it clean with deionized water. 2. Add 4g of anhydrous aluminum chloride and 12g of anhydrous zinc chloride in small amounts several times to a mixed solution of 90ml of anhydrous ethanol and 10ml of n-butanol, and stir magnetically until completely dissolved to obtain a transparent and homogeneous electrolyte. Anhydrous aluminum chloride, as the main corrosive salt, forms complex ions with chloride ions in the electrolyte, which is the main driving force for the electrochemical oxidation and complex dissolution of titanium during the anodic dissolution process. Anhydrous zinc chloride, as a leveling agent, introduces zinc ions that can regulate the cathode reaction process, optimize current distribution, and form adsorbent intermediate products on the anode surface, thereby inhibiting local over-corrosion, promoting micro-leveling, and obtaining a more uniform and smooth surface. Anhydrous ethanol serves as the primary solvent, providing basic dissolving power and conductivity. n-Butanol is used as an additive to adjust the viscosity, surface tension and evaporation rate of the electrolyte in order to improve the uniformity of the polished surface. 3. Place the electrolyte prepared in step 2 into an electrolytic cell. Under the dual-electrode system of electrolytic polishing with DC power, use the columnar stainless steel electrode, titanium electrode or platinum electrode placed in the electrolyte prepared in step 2 as the cathode, and use the pure titanium wire cleaned in step 1 placed in the electrolyte prepared in step 2, located inside the columnar stainless steel electrode, titanium electrode or platinum electrode and spaced 3 cm apart from it, as the anode. Apply a constant voltage of 60V for electrolytic polishing for 225s to reduce the diameter of the pure titanium wire cleaned in step 1. After the reduction, take out the titanium wire and perform anhydrous ethanol ultrasonic cleaning for 5 minutes, deionized water cleaning, nitrogen blowing and drying, and coating with one of rust-preventive oil or liquid paraffin for protection to obtain a titanium wire with a diameter of about 0.13mm after reduction and a bright surface. When the pure titanium wire anode, after being cleaned in step one, is located at the central axis of the columnar stainless steel electrode, titanium electrode, or platinum electrode cathode, the distance from each point on the cathode surface to the anode is basically equal, thus forming an axisymmetric uniform electric field distribution around the anode. This uniform electric field distribution can ensure that the current density at each point on the anode surface tends to be consistent, avoiding local current concentration or insufficiency caused by electric field distortion, thereby effectively suppressing the occurrence of uneven dissolution phenomena such as pitting and necking, which is the key guarantee for achieving uniform polishing of the circumferential surface of the titanium wire. 4. Add 0.02M triethanolamine to the electrolyte prepared in step 2, and stir magnetically until completely dissolved to prepare a new electrolyte. Triethanolamine, as a corrosion inhibitor, can be adsorbed on highly active sites on the surface of titanium wire, reduce local current density, slow down excessive dissolution, and effectively inhibit pitting and necking phenomena. It plays a key role in ensuring the dimensional stability and morphological integrity of ultrafine titanium wire during processing. 5. Place the electrolyte prepared in step 4 in an electrolytic cell in an ice-water bath at 0-5℃. Under the three-electrode constant current system of the electrochemical workstation, use the columnar stainless steel electrode, titanium electrode, or platinum electrode placed in the electrolyte prepared in step 4 as the counter electrode, and the titanium wire after diameter reduction in step 3, placed inside the columnar stainless steel electrode, titanium electrode, or platinum electrode in the electrolyte prepared in step 4 with a distance of 3cm from it, as the working electrode. Use a saturated calomel electrode as the reference electrode. Apply gradient constant current for deep polishing. Electrolyze at 0.20A for 4 minutes, then at 0.10A for 4 minutes, and then at 0.05A for 5 minutes to perform a second diameter reduction on the titanium wire after diameter reduction in step 3. After the second diameter reduction, take out the titanium wire after the second diameter reduction and perform anhydrous ethanol ultrasonic cleaning for 5 minutes, deionized water washing, nitrogen blowing and drying, and coating with one of the following for protection: rust-preventive oil or liquid paraffin. A superfine titanium wire with a diameter of about 0.042mm after the second diameter reduction is obtained.

[0028] Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were performed on the ultrafine titanium wire sample. The results are attached. Figure 2 The surface is smooth with no serious defects, the roughness Rq is 50.5 nm, the Ra is 51.5 nm, and the fracture rate is low. Example 2

[0029] 1. Immerse a 0.5mm diameter TA1 industrial pure titanium wire in an acid pickling solution prepared with 30ml hydrofluoric acid and 70ml deionized water for 60s. After the surface oxide layer is completely peeled off and a uniform silver-white color is revealed, take it out and rinse it clean with deionized water. 2. Add 4g of anhydrous aluminum chloride and 12g of anhydrous zinc chloride in small amounts several times to a mixed solution of 90ml of anhydrous ethanol and 10ml of n-butanol, and stir magnetically until completely dissolved to obtain a transparent and homogeneous electrolyte. 3. Place the electrolyte prepared in step 2 into an electrolytic cell. Under the dual-electrode system of electrolytic polishing with DC power, use the columnar stainless steel electrode, titanium electrode or platinum electrode placed in the electrolyte prepared in step 2 as the cathode, and use the pure titanium wire cleaned in step 1 placed in the electrolyte prepared in step 2, located inside the columnar stainless steel electrode, titanium electrode or platinum electrode and spaced 3 cm apart from it, as the anode. Apply a constant voltage of 60V for electrolytic polishing for 225s to reduce the diameter of the pure titanium wire cleaned in step 1. After the reduction, take out the titanium wire and perform anhydrous ethanol ultrasonic cleaning for 5 minutes, deionized water cleaning, nitrogen blowing and drying, and coating with one of rust-preventive oil or liquid paraffin for protection to obtain a titanium wire with a diameter of about 0.13mm after reduction and a bright surface. 4. Place the electrolyte prepared in step 2 in an electrolytic cell in an ice-water bath at 0-5℃. Under the three-electrode constant current system of the electrochemical workstation, use the columnar stainless steel electrode, titanium electrode, or platinum electrode placed in the electrolyte prepared in step 2 as the counter electrode, and the titanium wire after diameter reduction in step 3, placed in the electrolyte prepared in step 2 and located inside the columnar stainless steel electrode, titanium electrode, or platinum electrode with a distance of 3cm from it, as the working electrode. Use a saturated calomel electrode as the reference electrode. Apply constant current for deep polishing, and electrolyze with a constant current of 0.25A for 4 minutes to perform a second diameter reduction on the titanium wire after diameter reduction in step 3. After the second diameter reduction, take out the titanium wire after the second diameter reduction and perform ultrasonic cleaning with anhydrous ethanol for 5 minutes, washing with deionized water, drying with nitrogen, and protection with either anti-rust oil or liquid paraffin. A superfine titanium wire with a diameter of about 0.062mm after the second diameter reduction is obtained.

[0030] Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were performed on the ultrafine titanium wire sample. The results are attached. Figure 3 The results show that the current density is increased, the surface deteriorates significantly, large areas of uneven dark spots and local dissolution traces are visible, the roughness Rq is 85.9 nm, Ra is 87.1 nm, and the fracture rate is low. Example 3

[0031] 1. Immerse a 0.5mm diameter TA1 industrial pure titanium wire in an acid pickling solution prepared with 30ml hydrofluoric acid and 70ml deionized water for 60s. After the surface oxide layer is completely peeled off and a uniform silver-white color is revealed, take it out and rinse it clean with deionized water. 2. Add 3g of anhydrous aluminum chloride and 8g of anhydrous zinc chloride in small amounts several times to a mixed solution of 70ml of anhydrous ethanol and 30ml of n-butanol, and stir magnetically until completely dissolved to obtain a transparent and homogeneous electrolyte. 3. Place the electrolyte prepared in step 2 into an electrolytic cell. Under the dual-electrode system of electrolytic polishing with DC power, use the columnar stainless steel electrode, titanium electrode or platinum electrode placed in the electrolyte prepared in step 2 as the cathode, and use the pure titanium wire cleaned in step 1 placed in the electrolyte prepared in step 2, located inside the columnar stainless steel electrode, titanium electrode or platinum electrode and spaced 2 cm apart from it, as the anode. Apply a constant voltage of 50V for electrolytic polishing for 4 minutes to reduce the diameter of the pure titanium wire cleaned in step 1. After the reduction, take out the titanium wire and perform anhydrous ethanol ultrasonic cleaning for 5 minutes, deionized water cleaning, nitrogen blowing and drying, and coating with one of rust-preventive oil or liquid paraffin for protection to obtain a titanium wire with a diameter of about 0.12 mm after reduction and a bright surface. 4. Add 0.015M triethanolamine to the electrolyte prepared in step 2, and stir magnetically until completely dissolved to prepare a new electrolyte. 5. Place the electrolyte prepared in step 4 into an electrolytic cell in an ice-water bath at 0-5℃. Under the three-electrode constant current system of the electrochemical workstation, use the columnar stainless steel electrode, titanium electrode, or platinum electrode placed in the electrolyte prepared in step 4 as the counter electrode, and the titanium wire after diameter reduction in step 3, placed inside the columnar stainless steel electrode, titanium electrode, or platinum electrode in the electrolyte prepared in step 4 with a distance of 3cm from it, as the working electrode. Use a saturated calomel electrode as the reference electrode. Apply constant current for deep polishing, and electrolyze with a constant current of 0.20A for 4 minutes to perform a second diameter reduction on the titanium wire after diameter reduction in step 3. After the second diameter reduction, take out the titanium wire after the second diameter reduction and perform ultrasonic cleaning with anhydrous ethanol for 5 minutes, washing with deionized water, drying with nitrogen, and protection with either anti-rust oil or liquid paraffin. A superfine titanium wire with a diameter of about 0.085mm after the second diameter reduction is obtained.

[0032] Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were performed on the ultrafine titanium wire sample. The results are attached. Figure 4 The surface maintains good continuity and uniformity. The defects are mainly manifested as a few isolated dark spots, with no obvious grooves. The roughness Rq is 54.8 nm, Ra is 50.5 nm, and the fracture rate is low. Example 4

[0033] 1. Immerse a 0.5mm diameter TA1 industrial pure titanium wire in an acid pickling solution prepared with 30ml hydrofluoric acid and 70ml deionized water for 60s. After the surface oxide layer is completely peeled off and a uniform silver-white color is revealed, take it out and rinse it clean with deionized water. 2. Add 6g of anhydrous aluminum chloride and 12g of anhydrous zinc chloride in small amounts several times to a mixed solution of 90ml of anhydrous ethanol and 10ml of n-butanol, and stir magnetically until completely dissolved to obtain a transparent and homogeneous electrolyte. 3. Place the electrolyte prepared in step 2 into an electrolytic cell. Under the dual-electrode system of electrolytic polishing with DC power, use the columnar stainless steel electrode, titanium electrode or platinum electrode placed in the electrolyte prepared in step 2 as the cathode, and use the pure titanium wire cleaned in step 1, which is placed in the electrolyte prepared in step 2 and located inside the columnar stainless steel electrode, titanium electrode or platinum electrode with a distance of 4 cm from it, as the anode. Apply a constant voltage of 60V for electrolytic polishing for 225s to reduce the diameter of the pure titanium wire cleaned in step 1. After the reduction, take out the titanium wire and perform anhydrous ethanol ultrasonic cleaning for 5min, deionized water cleaning, nitrogen blowing and drying, and coating with one of rust-preventive oil or liquid paraffin for protection. The result is a titanium wire with a diameter of about 0.11mm after reduction, with a bright surface but slight corrosion spots visible in some areas. 4. Add 0.02M triethanolamine to the electrolyte prepared in step 2, and stir magnetically until completely dissolved to prepare a new electrolyte. 5. Place the electrolyte prepared in step 4 in an electrolytic cell in an ice-water bath at 0-5℃. Under the three-electrode constant current system of the electrochemical workstation, use the columnar stainless steel electrode, titanium electrode, or platinum electrode placed in the electrolyte prepared in step 4 as the counter electrode, and the titanium wire after diameter reduction in step 3, placed inside the columnar stainless steel electrode, titanium electrode, or platinum electrode in the electrolyte prepared in step 4 with a distance of 3cm from it, as the working electrode. Use a saturated calomel electrode as the reference electrode. Apply gradient constant current for deep polishing. Electrolyze at 0.20A for 4 minutes, then at 0.10A for 4 minutes, and then at 0.05A for 5 minutes to perform a second diameter reduction on the titanium wire after diameter reduction in step 3. After the second diameter reduction, take out the titanium wire after the second diameter reduction and perform anhydrous ethanol ultrasonic cleaning for 5 minutes, deionized water washing, nitrogen blowing and drying, and coating with one of the following for protection: rust-preventive oil or liquid paraffin. A superfine titanium wire with a diameter of about 0.040 mm after the second diameter reduction is obtained.

[0034] Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were performed on the ultrafine titanium wire sample. The results are attached. Figure 5 The results showed dense pitting on the surface, with a roughness Rq of 139.0 nm and Ra of 120.0 nm. The fracture rate was significantly increased, indicating that the excessive proportion of anhydrous aluminum chloride led to over-corrosion. Although the diameter could be reduced to a finer size, the surface quality was sacrificed. Example 5

[0035] 1. Immerse a 0.5mm diameter TA1 industrial pure titanium wire in an acid pickling solution prepared with 30ml hydrofluoric acid and 70ml deionized water for 60s. After the surface oxide layer is completely peeled off and a uniform silver-white color is revealed, take it out and rinse it clean with deionized water. 2. Add 4g of anhydrous aluminum chloride and 12g of anhydrous zinc chloride in small amounts several times to a mixed solution of 90ml of anhydrous ethanol and 10ml of n-butanol, and stir magnetically until completely dissolved to obtain a transparent and homogeneous electrolyte. 3. Place the electrolyte prepared in step 2 into an electrolytic cell. Under the dual-electrode system of electrolytic polishing with DC power, use the columnar stainless steel electrode, titanium electrode or platinum electrode placed in the electrolyte prepared in step 2 as the cathode, and use the pure titanium wire cleaned in step 1 placed in the electrolyte prepared in step 2, located inside the columnar stainless steel electrode, titanium electrode or platinum electrode and spaced 3 cm apart from it, as the anode. Apply a constant voltage of 60V for electrolytic polishing for 225s to reduce the diameter of the pure titanium wire cleaned in step 1. After the reduction, take out the titanium wire and perform anhydrous ethanol ultrasonic cleaning for 5 minutes, deionized water cleaning, nitrogen blowing and drying, and coating with one of rust-preventive oil or liquid paraffin for protection to obtain a titanium wire with a diameter of about 0.13mm after reduction and a bright surface. 4. Add 0.01M triethanolamine to the electrolyte prepared in step 2, and stir magnetically until completely dissolved to prepare a new electrolyte; 5. Place the electrolyte prepared in step 4 into an electrolytic cell in an ice-water bath at 0-5℃. Under the three-electrode constant current system of the electrochemical workstation, use the columnar stainless steel electrode, titanium electrode, or platinum electrode placed in the electrolyte prepared in step 4 as the counter electrode, and the titanium wire after diameter reduction in step 3, placed inside the columnar stainless steel electrode, titanium electrode, or platinum electrode in the electrolyte prepared in step 4 with a distance of 3cm from it, as the working electrode. Use a saturated calomel electrode as the reference electrode, apply constant current for deep polishing, and electrolyze at 0.05A for 15min to perform a second diameter reduction on the titanium wire after diameter reduction in step 3. After the second diameter reduction, take out the titanium wire after the second diameter reduction and perform ultrasonic cleaning with anhydrous ethanol for 5min, washing with deionized water, drying with nitrogen, and protection with either anti-rust oil or liquid paraffin. A superfine titanium wire with a diameter of about 0.112mm after the second diameter reduction is obtained.

[0036] Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were performed on the ultrafine titanium wire sample. The results are attached. Figure 6 The results show that the surface is relatively smooth, but the diameter reduction efficiency is significantly lower than that of Example 1. The roughness Rq is 56.4 nm and Ra is 50.6 nm, indicating that the transition between high and low currents without gradient is insufficient in the initial dissolution kinetics, thus limiting the diameter reduction effect. Example 6

[0037] 1. Immerse a 0.5mm diameter TA1 industrial pure titanium wire in an acid pickling solution prepared with 30ml hydrofluoric acid and 70ml deionized water for 60s. After the surface oxide layer is completely peeled off and a uniform silver-white color is revealed, take it out and rinse it clean with deionized water. 2. Add 4g of anhydrous aluminum chloride and 12g of anhydrous zinc chloride in small amounts several times to a mixed solution of 90ml of anhydrous ethanol and 10ml of n-butanol, and stir magnetically until completely dissolved to obtain a transparent and homogeneous electrolyte. 3. Place the electrolyte prepared in step 2 into an electrolytic cell. Under the dual-electrode system of electrolytic polishing with DC power, use the columnar stainless steel electrode, titanium electrode or platinum electrode placed in the electrolyte prepared in step 2 as the cathode, and use the pure titanium wire cleaned in step 1 placed in the electrolyte prepared in step 2, located inside the columnar stainless steel electrode, titanium electrode or platinum electrode and spaced 3 cm apart from it, as the anode. Apply a constant voltage of 60V for electrolytic polishing for 225s to reduce the diameter of the pure titanium wire cleaned in step 1. After the reduction, take out the titanium wire and perform anhydrous ethanol ultrasonic cleaning for 5 minutes, deionized water cleaning, nitrogen blowing and drying, and coating with one of rust-preventive oil or liquid paraffin for protection to obtain a titanium wire with a diameter of about 0.13mm after reduction and a bright surface. 4. Add 0.01M triethanolamine to the electrolyte prepared in step 2, and stir magnetically until completely dissolved to prepare a new electrolyte; 5. Place the electrolyte prepared in step 4 into an electrolytic cell at 25°C. Under the three-electrode constant current system of the electrochemical workstation, use the columnar stainless steel electrode, titanium electrode, or platinum electrode placed in the electrolyte prepared in step 4 as the counter electrode, and the titanium wire after diameter reduction in step 3, placed inside the columnar stainless steel electrode, titanium electrode, or platinum electrode in the electrolyte prepared in step 4 with a distance of 3 cm from it, as the working electrode. Use a saturated calomel electrode as the reference electrode. Apply gradient constant current for deep polishing. Electrolyze at 0.20A for 4 min, then at 0.10A for 4 min, and then at 0.05A for 5 min to perform a second diameter reduction on the titanium wire after diameter reduction in step 3. After the second diameter reduction, take out the titanium wire after the second diameter reduction and perform anhydrous ethanol ultrasonic cleaning for 5 min, deionized water washing, nitrogen blowing and drying, and coating with one of the following for protection: rust-preventive oil or liquid paraffin. A superfine titanium wire with a diameter of about 0.052 mm after the second diameter reduction is obtained.

[0038] Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were performed on the ultrafine titanium wire sample. The results are attached. Figure 7 The results showed obvious signs of overheating and localized ablation on the surface, with a roughness Rq of 83.7 nm and a Ra of 82.8 nm. The fracture rate was significantly increased, indicating that the ice-water bath is crucial for suppressing overheating and ensuring the stability of ultrafine filament processing.

[0039] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for low cost production of ultrafine titanium wire from ethanol based electrolyte, characterized in that, Includes the following steps:

1. Immerse the pure titanium wire in the pickling solution for pickling. After pickling, remove it and wash it with deionized water to remove the surface oxide layer.

2. Prepare an electrolyte by adding a chloride conductive salt to a mixed solution of organic alcohols; 3. Place the electrolyte prepared in step 2 into an electrolytic cell. Under the dual-electrode system of electrolytic polishing with DC power supply, use the columnar metal electrode in the electrolyte prepared in step 2 as the cathode and the pure titanium wire cleaned in step 1 and located inside the columnar metal electrode in the electrolyte prepared in step 2 as the anode. Apply constant voltage to electrolytic polish to reduce the diameter of the pure titanium wire cleaned in step 1. After the process is completed, take out the titanium wire and perform ultrasonic cleaning with anhydrous ethanol, washing with deionized water, drying with nitrogen, and oiling protection in sequence to obtain the titanium wire with reduced diameter.

4. Add the corrosion inhibitor to the electrolyte prepared in step 2 to prepare a new electrolyte; 5. Place the electrolyte prepared in step 4 into an electrolytic cell in an ice-water bath. Under the three-electrode constant current system of the electrochemical workstation, use the columnar metal electrode placed in the electrolyte prepared in step 4 as the counter electrode, and the titanium wire after diameter reduction in step 3 placed inside the columnar metal electrode in the electrolyte prepared in step 4 as the working electrode. Use a saturated calomel electrode as the reference electrode. Apply gradient constant current for deep polishing to perform secondary diameter reduction on the titanium wire after diameter reduction in step 3. After completion, take out the titanium wire after secondary diameter reduction and perform ultrasonic cleaning with anhydrous ethanol, washing with deionized water, drying with nitrogen, and oiling protection in sequence to obtain the ultrafine titanium wire after secondary diameter reduction.

2. A process for the low cost production of ultrafine titanium wires from ethanol based electrolyte as claimed in claim 1 wherein: In step one, the pickling solution is a mixture of strong acid and deionized water, and the volume ratio of the strong acid to the deionized water is 3:

7.

3. A process for the low cost production of ultrafine titanium wires from ethanol based electrolyte as claimed in claim 2, wherein: In step one, the strong acid is hydrofluoric acid.

4. A process for the low cost production of ultrafine titanium wires from ethanol based electrolyte as claimed in claim 3, wherein: In step two, the chloride conductive salt is a mixture of anhydrous aluminum chloride and anhydrous zinc chloride, and the mass ratio of the anhydrous aluminum chloride to the anhydrous zinc chloride is 1:2~4.

5. A process for the low cost production of ultrafine titanium wires from ethanol based electrolyte as claimed in claim 4 wherein: In step two, the organic alcohol mixture is a mixture of anhydrous ethanol and n-butanol, and the volume ratio of anhydrous ethanol to n-butanol is 2.1 to 9:

1.

6. A process for the low cost production of ultrafine titanium wires from ethanol based electrolyte as claimed in claim 5 wherein: In step three, the specific steps for reducing the diameter of the pure titanium wire cleaned in step one by applying constant voltage electropolishing are as follows: apply a constant voltage of 40~60V, electropolish for 3~5 minutes, and reduce the diameter of the pure titanium wire cleaned in step one to 0.10~0.24mm.

7. A process for the low cost production of ultrafine titanium wires from ethanol based electrolyte as claimed in claim 6 wherein: In step four, the corrosion inhibitor is triethanolamine, and the amount of triethanolamine added is 0M~0.06M.

8. A process for the low cost production of ultrafine titanium wires from ethanol based electrolyte as claimed in claim 7, wherein: In step five, the temperature of the ice-water bath is 0~5℃.

9. A process for the low cost production of ultrafine titanium wires from ethanol based electrolyte as claimed in claim 8, wherein: In steps three and five, the distance between the columnar metal electrode and the titanium wire is 2-4 cm.

10. A process for the low cost production of ultrafine titanium wires from ethanol based electrolyte as claimed in claim 9, wherein: In step five, the specific steps for applying gradient constant current for deep polishing to perform secondary diameter reduction on the titanium wire after diameter reduction in step three are as follows: first, apply 0.15~0.25A electrolysis for 0~6min, then apply 0.08~0.12A electrolysis for 0~4min, and then apply 0.03~0.06A electrolysis for 0~15min to reduce the diameter of the titanium wire after diameter reduction in step three to <0.05mm.

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