A cleaning and passivation method for small-diameter grooved special-shaped copper wire

Abstract

The present application belongs to the field of metal wire cleaning, and provides a cleaning and passivation method for special-shaped copper wire with grooves and small wire diameter; first, the copper wire is pre-blowed by an annular air knife to remove surface attachments, and is introduced into a groove guide water pipe; then, directional hot water consistent with the groove direction of the copper wire is used for strong flushing, and catechin gel mother liquor is added in the cleaning liquid and a brush is arranged for cooperative brushing; the copper wire is introduced into an ultrasonic cleaning tank for reciprocating deep purification, and the purified copper wire is introduced into a hot air duct arranged in the groove for deep dehydration and guide flow drying; the copper wire is introduced into a passivation chamber provided with an ultrasonic atomizer, and a passivation liquid containing a succinimidazole agent is atomized into uniform fine mist droplets to cover the copper wire; after the copper wire is finally dried by hot air, film formation and solidification are completed, and then the copper wire is wound, effectively solving the problems of difficult cleaning of special-shaped copper wire grooves and uneven passivation film, and improving the surface quality and oxidation resistance of the product.

Description

Technical Field

[0001] This invention belongs to the field of metal wire cleaning and relates to a cleaning and passivation method for small-diameter, grooved, irregularly shaped copper wires. Background Technology

[0002] In the fields of electronics, electrical engineering, and precision manufacturing, small-diameter grooved shaped copper wires are widely used due to their unique structure and excellent performance. However, during the drawing, forming, and handling processes, the surface of these copper wires, especially deep within the grooves, is highly susceptible to contamination such as drawing powder, oil, and metal shavings.

[0003] Existing copper wire cleaning methods are mostly designed for standard round wires, typically employing simple immersion, spraying, or conventional ultrasonic cleaning. When these methods are applied to irregularly shaped copper wires with grooves, the results are often unsatisfactory. Simple spraying struggles to reach the bottom of the tiny grooves, creating cleaning dead zones; while conventional immersion and ultrasonic cleaning can remove some contaminants, their effectiveness is insufficient for firmly adhering drawing powder and oil, making thorough purification difficult. Furthermore, in continuous production lines, cross-contamination between processes is common, significantly reducing the cleaning effect.

[0004] In terms of anti-oxidation treatment, traditional passivation processes often employ an immersion method, where the copper wire is directly passed through a passivation tank. For complex, irregularly shaped copper wires, the immersion method is prone to generating air bubbles within the tank, preventing the passivation solution from uniformly contacting the metal surface and creating defects in the passivation film. Furthermore, if drying is incomplete after passivation, residual liquid can damage the integrity of the passivation film, affecting its long-term corrosion protection. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a cleaning and passivation method for small-diameter, grooved, irregularly shaped copper wires. This method utilizes the combined action of directional high-pressure flushing along the grooves and brush washing, supplemented by ultrasonic deep purification, to effectively remove stubborn contaminants from the grooves. Furthermore, ultrasonic atomization technology is employed to atomize the passivation solution, allowing it to penetrate and cover the surface of the copper wire and the interior of the grooves, forming a uniform and dense protective film, thereby meeting the needs of actual production.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a method for cleaning and passivating small-diameter, grooved, irregularly shaped copper wire, the method comprising:

[0008] S1, the copper wire is pre-blown by an annular air knife to remove liquid and dust from its surface, and then introduced into a tee-shaped guide water pipe arranged coaxially with the outer contour of the wire. The guide water pipe and the wire are fitted with a clearance limit.

[0009] S2, when the copper wire passes through the guide water pipe, directional hot water flushing is carried out in the same direction as the groove. CO2 is introduced at the same time as directional hot water flushing. After the directional hot water flushing is completed, the brush section is entered, the CO2 is stopped, catechin gel mother liquor is added to the cleaning solution, and the brush is set up to cooperate with the synchronous spray cleaning solution for brushing. The inter-section dehydration and isolation is carried out by an annular air knife.

[0010] S3, copper wire is introduced into ultrasonic cleaning tank, and reciprocating wire is achieved by multi-slot wire guide wheel. At the end of the section, an annular air knife is set for secondary dehydration and isolation.

[0011] S4. The copper wire is introduced into a three-way hot air duct arranged in the same direction as the groove for deep dehydration and flow drying along the groove. Then it enters the passivation chamber equipped with an ultrasonic atomizer for atomization and coverage. Succinyl imidazole agent is added to the passivation liquid. A hot air knife is set at the exit of the chamber for purging.

[0012] S5, the copper wire is dried with hot air to form a film and solidify, and then wound up after cooling.

[0013] The copper wire first passes through an annular air knife, which peels off and blows away weakly bonded liquid and dust particles adhering to the surface from the metal substrate. Entering the core cleaning stage, a directional high-pressure hot water stream aligned with the grooves in the copper wire is applied to the wire surface. The heat energy first reduces the viscosity of the adhering oil, increasing its fluidity; simultaneously, the kinetic energy of the high-pressure water stream is converted into impact and scouring force against the contaminants. Its directional design ensures the water flow vector follows the tangential direction of the grooves, thus shearing and carrying contaminants outward from the grooves rather than pushing them deeper. During this process, carbon dioxide introduced into the cleaning solution dissolves in water to form carbonic acid, creating a weakly acidic system. The hydrogen ions in this system react with the inevitably present copper oxide or cuprous oxide on the copper wire surface, generating water-soluble copper salts, thereby chemically removing the thin layer of metal oxide and exposing the fresh copper substrate. Simultaneously introduced catechin gel mother liquor exerts multiple synergistic effects: the catechin groups in its molecular structure have extremely strong adhesion and complexing ability to metal surfaces and various contaminants, actively adsorbing and encapsulating contaminant particles; the polycationic fragments on the molecular chain capture negatively charged fine dust through electrostatic attraction; while the polyanionic fragments act as highly efficient dispersants, immediately encapsulating contaminants once they are peeled off, preventing them from re-aggregating or redepositing on the copper wire surface in the solution through electrostatic repulsion and steric hindrance. Next, synchronously operating brushes, through mechanical contact, allow their bristles to penetrate the bottom of the groove geometry, applying direct shearing and frictional forces to forcibly peel off stubborn contaminants. After this stage, an annular air knife acts again, thoroughly blowing away the waste cleaning liquid carrying a large amount of peeled contaminants from the wire surface, preventing it from entering the next purification stage, thus forming a crucial inter-stage contamination isolation. Subsequently, the copper wire enters the ultrasonic cleaning tank, where high-frequency ultrasound induces cavitation in the tank solution, loosening and peeling off fine residual particles, achieving deep physical purification. The multi-slot reciprocating routing design extends the effective time of ultrasonic cavitation. The secondary dehydration isolation air knife at the end of the section ensures that the cleaning medium carrying a very small amount of residual particles is removed.

[0014] Before passivation, the copper wire passes through a hot air duct arranged in a groove. The convective heat transfer of the hot compressed air causes the trace moisture remaining on the wire surface to evaporate rapidly. The airflow organization in the groove enhances the turbulence inside the groove, accelerating the mass transfer process of water vapor from the depth of the groove to the mainstream air, achieving thorough drying inside the groove and creating an anhydrous interface condition for the uniform formation of the subsequent passivation film. Next, the copper wire enters the passivation chamber, where an ultrasonic atomizer excites the passivation liquid containing succinyl imidazole into an aerosol with a median diameter of submicron. This aerosol can penetrate and fill the complex groove structure of the copper wire, uniformly depositing on the exposed metal surface, overcoming the bubble shielding effect caused by surface tension in the liquid immersion method. The succinyl imidazole molecule, as the core functional group, has a nitrogen atom on its imidazole ring containing lone pairs of electrons, which can form stable coordination bonds with the empty electron orbitals on the surface of copper atoms, allowing the molecule to be firmly anchored to the copper surface through chemical adsorption. The other end of the molecule, the hydrophobic hydrocarbon chain, extends outwards, eventually self-assembling into a dense monomolecular or multimolecular hydrophobic physical barrier film. This film effectively isolates the copper substrate from corrosive media such as oxygen and water vapor. Ultimately, a solid protective film with a stable physical structure and uniform chemical properties is formed, thus completing the entire cleaning and passivation process.

[0015] As a preferred technical solution of the present invention, in S1, the pre-blowing air supply pressure is 0.5-0.8 MPa and the temperature is 20-40℃. For example, the air supply pressure can be (0.5, 0.53, 0.56, 0.59, 0.62, 0.65, 0.68, 0.71, 0.74, 0.77 or 0.8) MPa and the temperature can be (20, 22, 24, 26, 28, 30, 32, 34, 36, 38 or 40)℃, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0016] In some alternative embodiments, the clearance fit is 0.5-0.8 mm, for example, it can be (0.5, 0.53, 0.56, 0.59, 0.62, 0.65, 0.68, 0.71, 0.74, 0.77 or 0.8) mm, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0017] As a preferred technical solution of the present invention, in S2, during the directional hot water flushing process, the hot water temperature is 60-75℃, the flushing pressure is provided by a high-pressure pump with a head ≥30m, and the single-stage flushing time is 0.07-0.15s. For example, the hot water temperature can be (60, 61.5, 63, 64.5, 66, 67.5, 69, 70.5, 72, 73.5 or 75)℃, the flushing pressure is provided by a high-pressure pump with a head ≥30m, and the single-stage flushing time is (0.07, 0.08, 0.09, 0.1, 0.11, 0.12, 0.13, 0.14 or 0.15)s, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0018] In some optional embodiments, the dissolved carbon dioxide concentration during the directional hot water flushing process is 800-1500 ppm, for example, it can be a dissolved concentration of (800, 870, 940, 1010, 1080, 1150, 1220, 1290, 1360, 1430 or 1500) ppm, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0019] In some optional embodiments, the addition of catechin gel stock solution to the cleaning solution results in a solid content of 200-350 ppm and a pH of 7.8-8.8. For example, the solid content of the cleaning solution can be (200, 215, 230, 245, 260, 275, 290, 305, 320, 335 or 350) ppm, and the pH of the cleaning solution can be (7.8, 7.9, 8.0, 8.1, 8.2, 8.3, 8.4, 8.5, 8.6, 8.7 or 8.8), but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0020] In some optional embodiments, the brush diameter is 90-120 mm, the rotation speed is 400-600 rpm, and the brushing time is 3-8 s. For example, the brush diameter can be (90, 93, 96, 99, 102, 105, 108, 111, 114, 117 or 120) mm, the rotation speed can be (400, 420, 440, 460, 480, 500, 520, 540, 560, 580 or 600) rpm, and the brushing time can be (3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5 or 8.0) s, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0021] In some optional embodiments, the annular air knife has an air supply pressure of 0.5-0.8 MPa and a purging time of 2-5 s. For example, the air supply pressure can be (0.5, 0.53, 0.56, 0.59, 0.62, 0.65, 0.68, 0.71, 0.74, 0.77 or 0.8) MPa and the purging time can be (2.0, 2.3, 2.6, 2.9, 3.2, 3.5, 3.8, 4.1, 4.4, 4.7 or 5.0) s, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0022] In some optional embodiments, the preparation method of the catechin gel mother liquor is as follows: a polyethyleneimine solution is mixed with deionized water to obtain solution A; dopamine hydrochloride is dissolved in phosphate buffer solution and sodium periodate is added for pre-oxidation to obtain solution B; solution B is added dropwise to solution A for reaction; 3-chloro-2-hydroxypropanesulfonate sodium solution is added to a first temperature for reaction to obtain a zwitterionic solution; polyacrylic acid is dissolved in water and EDC·HCl (1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride) and NHS (N-hydroxysuccinimide) are added for activation to obtain an activation solution; the activation solution is added dropwise to the zwitterionic solution for reaction; and the solution is dialyzed, concentrated, and filtered to obtain the catechin gel mother liquor.

[0023] In some optional embodiments, the mass ratio of the polyethyleneimine solution, deionized water, dopamine hydrochloride, phosphate buffer solution, sodium periodate, sodium 3-chloro-2-hydroxypropanesulfonate solution, polyacrylic acid, water, EDC·HCl, and NHS is (70-90):(350-450):(6-10):(80-120):(0.6-1):(30-56):(12-18):(80-120):(6-10):(3-6) For example, it could be (70, 72, 74, 76, 78, 80, 82, 84, 86, 88 or 90); (350, 360, 370, 380, 390, 400, 410, 420, 430, 440 or 450); (6, 6.4, 6.8, 7.2, 7.6, 8.0, 8.4, 8.8, 9.2, 9.6 or 10); (80, 84, 88, 92, 96, 100, 104, 108, 112, ... 116 or 120: (0.6, 0.64, 0.68, 0.72, 0.76, 0.8, 0.84, 0.88, 0.92, 0.96 or 1): (30, 32.6, 35.2, 37.8, 40.4, 43, 45.6, 48.2, 50.8, 53.4 or 56): (12, 12.6, 13.2, 13.8, 14.4, 15, 15.6, 16.2, 16.8, 17.4 or 18) (80, 84, 88, 92, 96, 100, 104, 108, 112, 116 or 120): (6, 6.4, 6.8, 7.2, 7.6, 8.0, 8.4, 8.8, 9.2, 9.6 or 10): (3.0, 3.3, 3.6, 3.9, 4.2, 4.5, 4.8, 5.1, 5.4, 5.7 or 6.0), but not limited to the listed values; other unlisted values ​​within this range also apply.

[0024] In some optional embodiments, the polyethyleneimine solution has a mass fraction of 50 wt.%.

[0025] In some alternative embodiments, the phosphate buffer solution has a concentration of 0.01 M and a pH of 7-7.6, for example, a pH of (7.0, 7.06, 7.12, 7.18, 7.24, 7.3, 7.36, 7.42, 7.48, 7.54 or 7.6), but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0026] In some optional embodiments, the pre-oxidation time is 0.05-0.1 h, for example, it can be 0.05 h, 0.055 h, 0.06 h, 0.065 h, 0.07 h, 0.075 h, 0.08 h, 0.085 h, 0.09 h, 0.095 h or 0.1 h, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0027] In some optional embodiments, the reaction time for adding solution B to solution A is 1.5-2.5 h, for example, it can be 1.5 h, 1.6 h, 1.7 h, 1.8 h, 1.9 h, 2.0 h, 2.1 h, 2.2 h, 2.3 h, 2.4 h or 2.5 h, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0028] In some alternative embodiments, the first temperature is 55-65°C, for example, it can be 55°C, 56°C, 57°C, 58°C, 59°C, 60°C, 61°C, 62°C, 63°C, 64°C or 65°C, but is not limited to the listed values, other unlisted values ​​within this range are also applicable.

[0029] In some optional embodiments, the mass fraction of the sodium 3-chloro-2-hydroxypropanesulfonate solution is 20-45 wt.%, for example, it can be 20 wt.%, 22.5 wt.%, 25 wt.%, 27.5 wt.%, 30 wt.%, 32.5 wt.%, 35 wt.%, 37.5 wt.%, 40 wt.%, 42.5 wt.%, or 45 wt.%, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0030] In some optional embodiments, the reaction time for adding sodium 3-chloro-2-hydroxypropanesulfonate solution is 5-7 hours, for example, 5.0 hours, 5.2 hours, 5.4 hours, 5.6 hours, 5.8 hours, 6.0 hours, 6.2 hours, 6.4 hours, 6.6 hours, 6.8 hours, or 7.0 hours, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0031] In some optional embodiments, the polyacrylic acid is dissolved in water and activated with EDC·HCl and NHS for 0.4-0.6 hours, for example, 0.4 hours, 0.42 hours, 0.44 hours, 0.46 hours, 0.48 hours, 0.5 hours, 0.52 hours, 0.54 hours, 0.56 hours, 0.58 hours or 0.6 hours, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0032] In some optional embodiments, the reaction time for adding the solution to the zwitterionic solution is 5-7 hours, for example, 5.0 hours, 5.2 hours, 5.4 hours, 5.6 hours, 5.8 hours, 6.0 hours, 6.2 hours, 6.4 hours, 6.6 hours, 6.8 hours, or 7.0 hours, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0033] As a preferred technical solution of the present invention, in S3, the temperature of the liquid in the ultrasonic cleaning tank is 35-45℃ and the ultrasonic frequency is 35-40kHz. For example, the liquid temperature can be (35, 36, 37, 38, 39, 40, 41, 42, 43, 44 or 45)℃ and the ultrasonic frequency can be (35, 35.5, 36, 36.5, 37, 37.5, 38, 38.5, 39, 39.5 or 40)kHz, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0034] In some optional embodiments, the multi-slot wire guide roller has a single roller diameter > 400mm, a center distance between adjacent wire guide rollers of 1.5-2.5m, 6-8 wire guide slots, and an equivalent dwell time of 10-30s for reciprocating wire travel. For example, it can be: a single roller diameter > 400mm, a center distance between adjacent wire guide rollers of (1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4 or 2.5)m, a wire guide slot of (6, 6.2, 6.4, 6.6, 6.8, 7, 7.2, 7.4, 7.6, 7.8 or 8), and an equivalent dwell time of (10, 12, 14, 16, 18, 20, 22, 24, 26, 28 or 30)s, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0035] As a preferred technical solution of the present invention, in S4, the temperature of the hot compressed air in the three-way hot air duct is 60-75℃, the air supply pressure is 0.5-0.8MPa, and the processing time is 0.07-0.15s. For example, the hot compressed air temperature can be (60, 61.5, 63, 64.5, 66, 67.5, 69, 70.5, 72, 73.5 or 75)℃, the air supply pressure can be (0.5, 0.53, 0.56, 0.59, 0.62, 0.65, 0.68, 0.71, 0.74, 0.77 or 0.8)MPa, and the processing time can be (0.07, 0.08, 0.09, 0.1, 0.11, 0.12, 0.13, 0.14 or 0.15)s, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0036] In some optional embodiments, the passivation chamber is set at a room temperature of 25-35°C, a droplet median diameter D50 of 0.1-0.5 μm, and atomization time of 3-10 s. For example, the room temperature can be (25, 26, 27, 28, 29, 30, 31, 32, 33, 34, or 35)°C, the droplet median diameter D50 can be (0.1, 0.14, 0.18, 0.22, 0.26, 0.3, 0.34, 0.38, 0.42, 0.46, or 0.5) μm, and the atomization time can be (3.0, 3.7, 4.4, 5.1, 5.8, 6.5, 7.2, 7.9, 8.6, 9.3, or 10.0) s, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0037] In some optional embodiments, the temperature of the hot air knife is 30-40°C, the air supply pressure is 0.5-0.8 MPa, and the purging time is 2-5 s. For example, the temperature can be (30, 31, 32, 33, 34, 35, 36, 37, 38, 39 or 40)°C, the air supply pressure can be (0.5, 0.53, 0.56, 0.59, 0.62, 0.65, 0.68, 0.71, 0.74, 0.77 or 0.8) MPa, and the purging time can be (2.0, 2.3, 2.6, 2.9, 3.2, 3.5, 3.8, 4.1, 4.4, 4.7 or 5.0) s, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0038] In some optional embodiments, the addition of succinyl imidazole to the passivation solution results in a succinyl imidazole mass fraction of 0.08-0.20 wt.% and a passivation solution pH of 6.0-6.6. For example, the succinyl imidazole mass fraction in the passivation solution could be (0.08, 0.092, 0.104, 0.116, 0.128, 0.14, 0.152, 0.164, 0.176, 0.188, or 0.20) wt%, and the passivation solution pH could be (6.0, 6.06, 6.12, 6.18, 6.24, 6.3, 6.36, 6.42, 6.48, 6.54, or 6.6), but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0039] In some optional embodiments, the preparation method of the succinyl imidazole agent is as follows: 1-(3-aminopropyl)imidazole and succinic anhydride are dispersed in acetone, reacted in an ice-water bath and stirred at room temperature, and distilled under reduced pressure to obtain a viscous substance. Deionized water is added and stirred, and sodium hydroxide solution is added dropwise. The mixture is filtered and concentrated under reduced pressure to obtain the succinyl imidazole agent.

[0040] In some optional embodiments, the mass ratio of 1-(3-aminopropyl)imidazole, succinic anhydride, acetone, deionized water, and sodium hydroxide solution is (100-130):(90-110):(250-350):(400-600):(20-40), for example, (100, 103, 106, 109, 112, 115, 118, 121, 124, 127, or 130):(90, 92, 94, 96, 98, 100, 102, 10...). 4, 106, 108 or 110: (250, 260, 270, 280, 290, 300, 310, 320, 330, 340 or 350): (400, 420, 440, 460, 480, 500, 520, 540, 560, 580 or 600): (20, 22, 24, 26, 28, 30, 32, 34, 36, 38 or 40), but not limited to the listed values, other unlisted values ​​within this range also apply.

[0041] In some optional embodiments, the ice-water bath reaction time is 2-4 hours, for example, 2.0 hours, 2.2 hours, 2.4 hours, 2.6 hours, 2.8 hours, 3.0 hours, 3.2 hours, 3.4 hours, 3.6 hours, 3.8 hours, or 4.0 hours, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0042] In some optional embodiments, the stirring time at room temperature is 4-8 hours, for example, 4.0 hours, 4.4 hours, 4.8 hours, 5.2 hours, 5.6 hours, 6.0 hours, 6.4 hours, 6.8 hours, 7.2 hours, 7.6 hours, or 8.0 hours, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0043] In some optional embodiments, the sodium hydroxide solution has a mass fraction of 30 wt.%.

[0044] Compared with existing technologies, the beneficial effects of this invention are as follows: This method combines directional high-pressure hot water flushing with physical brush washing, and utilizes a groove design consistent with the groove direction to achieve targeted and powerful removal of dirt deep in the grooves of irregularly shaped copper wires. The cleaning effect is thorough and superior to traditional soaking or conventional spraying methods. By introducing catechin gel mother liquor into the cleaning solution, the peeling and dispersion ability of oil stains and metal dust is enhanced. At the same time, the weakly acidic environment created by carbon dioxide further improves the cleaning efficiency, and the process is environmentally friendly. The passivation solution containing succinyl imidazole is applied in the form of micro-droplets, ensuring that the passivation solution can uniformly penetrate and adhere to the complex groove structure surface of the copper wire. The resulting passivation film is dense, complete, and free of bubble defects, improving the oxidation resistance and corrosion resistance of the copper wire. Detailed Implementation

[0045] The technical solution of the present invention will be described in detail below with reference to specific embodiments. The embodiments described herein are specific implementations of the present invention and are used to illustrate the concept of the present invention; these descriptions are explanatory and exemplary and should not be construed as limiting the implementation of the present invention or the scope of protection of the present invention. In addition to the embodiments described herein, those skilled in the art can also adopt other obvious technical solutions based on the content disclosed in the claims and the specification of this application. These technical solutions include those that make any obvious substitutions and modifications to the embodiments described herein.

[0046] The chemical reagents used in the embodiments and comparative examples of this invention are all commercially available products and have not undergone any further purification treatment.

[0047] Example 1

[0048] This embodiment provides a cleaning and passivation method for small-diameter, grooved, irregularly shaped copper wires, the method specifically including the following steps:

[0049] S1, the copper wire is pre-blown by an annular air knife to remove liquid and dust from its surface. The air supply pressure for the pre-blowing is 0.5MPa and the temperature is 40℃. A tee-shaped water guide pipe is introduced along the groove and arranged coaxially with the outer contour of the wire. The water guide pipe and the wire are fitted with a clearance of 0.8mm.

[0050] S2, when the copper wire passes through the guide water pipe, directional hot water flushing is performed in accordance with the direction of the groove. During the directional hot water flushing, the hot water temperature is 60℃, the flushing pressure is provided by a high-pressure pump with a head of ≥30m, the single-stage flushing time is 0.15s, and the carbon dioxide concentration during the directional hot water flushing is 800ppm. After the directional hot water flushing is completed, the section enters the brush section, the CO2 supply is stopped, catechin gel stock solution is added to the cleaning solution, and the brush is set up in conjunction with the synchronous spray cleaning solution for brushing. An annular air knife is used for inter-stage dehydration and isolation. The brush diameter is 120mm, the rotation speed is 400rpm, the brushing time is 8s, and the air supply pressure of the annular air knife is 0.5. The preparation method of the catechin gel mother liquor is as follows: 70g of polyethyleneimine solution with a mass fraction of 50wt.% is mixed with 450g of deionized water to obtain solution A; 10g of dopamine hydrochloride is dissolved in 80g of phosphate buffer solution with a mass fraction of 0.01M and a pH of 7.6, and 0.6g of sodium periodate is added for pre-oxidation for 0.1h to obtain solution B; solution B is added dropwise to solution A and reacted for 2.5h; the temperature is raised to 55℃ and 56g of sodium 3-chloro-2-hydroxypropanesulfonate solution with a mass fraction of 20wt.% is added and reacted for 5h to obtain a zwitterionic solution; 18g of polyacrylic acid is dissolved in 80g of water and 10g of EDC·HCl and 3g of NHS are added for activation for 0.6h to obtain activation solution; activation solution is added dropwise to zwitterionic solution and reacted for 7h; dialyzed, concentrated, and filtered to obtain catechin gel mother liquor;

[0051] S3, the copper wire is introduced into the ultrasonic cleaning tank. The temperature of the liquid in the ultrasonic cleaning tank is 35℃ and the ultrasonic frequency is 40kHz. The wire is reciprocated by a multi-slot wire guide wheel. The diameter of a single multi-slot wire guide wheel is >400mm, the center distance between adjacent wire guide wheels is 2.5m, the number of wire guide slots is 6, and the equivalent dwell time of the reciprocating wire is 30s. An annular air knife is set at the end of the section for secondary dehydration and isolation.

[0052] S4. The copper wire is guided into a three-way hot air duct aligned with the groove direction for deep dehydration and flow-guiding drying along the groove. In the three-way hot air duct, the temperature of the hot compressed air is 75℃, the supply pressure is 0.5MPa, and the processing time is 0.15s. Subsequently, it enters a passivation chamber equipped with an ultrasonic atomizer for atomization coverage. In the passivation chamber, the room temperature is 35℃, the median droplet diameter (D50) is 0.1μm, and the atomization time is 10s. Succinylated imidazole is added to the passivation solution to achieve a mass fraction of 0.20wt.% and a pH of 6.0. The preparation method of the succinylated imidazole is as follows: 130g... 1-(3-aminopropyl)imidazole was dispersed with 90g of succinic anhydride in 350g of acetone and reacted in an ice-water bath for 4h. Then, the mixture was stirred at room temperature for 4h. The mixture was distilled under reduced pressure to obtain a viscous substance. 600g of deionized water was added and stirred, and 20g of sodium hydroxide solution with a mass fraction of 30wt.% was added dropwise. The mixture was filtered and concentrated under reduced pressure to obtain succinylimidazole. A hot air knife was set at the outlet of the chamber for purging. The temperature of the hot air knife was 40℃, the air supply pressure was 0.5MPa, and the purging time was 5s.

[0053] S5, the copper wire is dried with hot air to form a film and solidify, and then wound up after cooling.

[0054] Example 2

[0055] This embodiment provides a cleaning and passivation method for small-diameter, grooved, irregularly shaped copper wires, the method specifically including the following steps:

[0056] S1, the copper wire is pre-blown by an annular air knife to remove liquid and dust from its surface. The air supply pressure for the pre-blowing is 0.8MPa and the temperature is 20℃. A tee-shaped water guide pipe is introduced along the groove and arranged coaxially with the outer contour of the wire. The water guide pipe and the wire are fitted with a clearance of 0.5mm.

[0057] S2, when the copper wire passes through the guide water pipe, directional hot water flushing is carried out in the same direction as the groove. During the directional hot water flushing, the hot water temperature is 75℃, the flushing pressure is provided by a high-pressure pump with a head of ≥30m, the single-stage flushing time is 0.07s, the carbon dioxide concentration during the directional hot water flushing is 1500ppm, after the directional hot water flushing is completed, the brush section is entered, the CO2 supply is stopped, catechin gel mother liquor is added to the cleaning solution, the brush is set up in conjunction with the synchronous spray cleaning solution for brushing, and the inter-stage dehydration and isolation is performed by an annular air knife. The brush diameter is 90mm, the rotation speed is 600rpm, the brushing time is 3s, and the air supply pressure of the annular air knife is 0. The preparation method of the catechin gel mother liquor is as follows: 90g of 50wt% polyethyleneimine solution is mixed with 350g of deionized water to obtain solution A. 6g of dopamine hydrochloride is dissolved in 120g of 0.01M phosphate buffer solution with pH 7 and 1.0g of sodium periodate is added for pre-oxidation for 0.05h to obtain solution B. Solution B is added dropwise to solution A and reacted for 1.5h. The temperature is raised to 65℃ and 30g of 45wt.% sodium 3-chloro-2-hydroxypropanesulfonate solution is added and reacted for 7h to obtain a zwitterionic solution. Separately, 12g of polyacrylic acid is dissolved in 120g of water and 6g of EDC·HCl and 6g of NHS are added for activation for 0.4h to obtain an activation solution. The activation solution is added dropwise to the zwitterionic solution and reacted for 5h. The solution is then dialyzed, concentrated, and filtered to obtain the catechin gel mother liquor.

[0058] S3, the copper wire is introduced into the ultrasonic cleaning tank. The temperature of the liquid in the ultrasonic cleaning tank is 45℃ and the ultrasonic frequency is 35kHz. The wire is reciprocated through a multi-slot wire guide wheel. The diameter of a single multi-slot wire guide wheel is >400mm, the center distance between adjacent wire guide wheels is 1.5m, the number of wire guide slots is 8, and the equivalent dwell time of the reciprocating wire is 10s. A ring-shaped air knife is set at the end of the section for secondary dehydration and isolation.

[0059] S4. The copper wire is introduced into a three-way hot air duct aligned with the groove direction for deep dehydration and flow-guiding drying along the groove. In the three-way hot air duct, the temperature of the hot compressed air is 60℃, the supply pressure is 0.8MPa, and the processing time is 0.07s. Subsequently, it enters a passivation chamber equipped with an ultrasonic atomizer for atomization coverage. In the passivation chamber, the room temperature is 25℃, the median droplet diameter (D50) is 0.5μm, and the atomization time is 3s. Succinylated imidazole is added to the passivation solution to achieve a mass fraction of 0.08wt.% and a pH of 6.6. The preparation method of the succinylated imidazole is as follows: 100g... 1-(3-aminopropyl)imidazole was dispersed with 110g of succinic anhydride in 250g of acetone and reacted in an ice-water bath for 2h. Then, the mixture was stirred at room temperature for 8h. The mixture was distilled under reduced pressure to obtain a viscous substance. 400g of deionized water was added and stirred, and 40g of sodium hydroxide solution with a mass fraction of 30wt.% was added dropwise. The mixture was filtered and concentrated under reduced pressure to obtain succinylimidazole. A hot air knife was set at the outlet of the chamber for purging. The temperature of the hot air knife was 30℃, the air supply pressure was 0.8MPa, and the purging time was 2s.

[0060] S5, the copper wire is dried with hot air to form a film and solidify, and then wound up after cooling.

[0061] Example 3

[0062] This embodiment provides a cleaning and passivation method for small-diameter, grooved, irregularly shaped copper wires, the method specifically including the following steps:

[0063] S1, the copper wire is pre-blown by an annular air knife to remove liquid and dust from its surface. The air supply pressure for the pre-blowing is 0.6MPa and the temperature is 30℃. A tee-shaped water guide pipe is introduced along the groove and arranged coaxially with the outer contour of the wire. The water guide pipe and the wire are fitted with a clearance of 0.6mm.

[0064] S2, when the copper wire passes through the guide water pipe, directional hot water flushing is performed in accordance with the direction of the groove. During the directional hot water flushing, the hot water temperature is 65℃, the flushing pressure is provided by a high-pressure pump with a head of ≥30m, the single-stage flushing time is 0.1s, and the carbon dioxide concentration during the directional hot water flushing is 1000ppm. After the directional hot water flushing is completed, the section enters the brush section, the CO2 supply is stopped, catechin gel stock solution is added to the cleaning solution, and the brush is set up in conjunction with the synchronous spray cleaning solution for brushing. An annular air knife is used for inter-stage dehydration and isolation. The brush diameter is 100mm, the rotation speed is 500rpm, the brushing time is 5s, and the air supply pressure of the annular air knife is 0.6M. Pa, purge time is 3s, the preparation method of the catechin gel mother liquor is as follows: 80g of polyethyleneimine solution with a mass fraction of 50wt.% is mixed with 400g of deionized water to obtain solution A; 8g of dopamine hydrochloride is dissolved in 100g of phosphate buffer solution with a mass fraction of 0.01M and a pH of 7.2 and 0.8g of sodium periodate is added for pre-oxidation for 0.08h to obtain solution B; solution B is added dropwise to solution A and reacted for 2.0h; the temperature is raised to 60℃ and 40g of sodium 3-chloro-2-hydroxypropanesulfonate solution is added and reacted for 6h to obtain a zwitterionic solution; 15g of polyacrylic acid is dissolved in 100g of water and 8g of EDC·HCl and 4g of NHS are added for activation for 0.5h to obtain activation solution; activation solution is added dropwise to zwitterionic solution and reacted for 6h; dialyzed, concentrated and filtered to obtain catechin gel mother liquor;

[0065] S3, the copper wire is introduced into the ultrasonic cleaning tank. The temperature of the liquid in the ultrasonic cleaning tank is 40℃ and the ultrasonic frequency is 38kHz. The wire is reciprocated by a multi-slot wire guide wheel. The diameter of a single multi-slot wire guide wheel is >400mm, the center distance between adjacent wire guide wheels is 2.0m, the number of wire guide slots is 7, and the equivalent dwell time of the reciprocating wire is 20s. An annular air knife is set at the end of the section for secondary dehydration and isolation.

[0066] S4. The copper wire is guided into a three-way hot air duct arranged in the same direction as the groove for deep dehydration and flow-guiding drying along the groove. In the three-way hot air duct, the temperature of the hot compressed air is 65℃, the supply pressure is 0.6MPa, and the processing time is 0.1s. Then, it enters a passivation chamber equipped with an ultrasonic atomizer for atomization coverage. In the passivation chamber, the room temperature is 30℃, the median diameter D50 of the droplets is 0.3μm, the atomization time is 6s, and succinyl imidazole agent is added to the passivation solution to make the mass fraction of succinyl imidazole agent in the passivation solution 0.15wt.%, and the pH of the passivation solution is 6.2. The preparation method of the succinyl imidazole agent is as follows: 110g 1-(3-aminopropyl)imidazole was dispersed with 100g of succinic anhydride in 300g of acetone and reacted in an ice-water bath for 3h. Then, the mixture was stirred at room temperature for 6h. The mixture was distilled under reduced pressure to obtain a viscous substance. 500g of deionized water was added and stirred, and 30g of sodium hydroxide solution with a mass fraction of 30wt.% was added dropwise. The mixture was filtered and concentrated under reduced pressure to obtain succinylimidazole. A hot air knife was set at the outlet of the chamber for purging. The temperature of the hot air knife was 35℃, the air supply pressure was 0.6MPa, and the purging time was 3s.

[0067] S5, the copper wire is dried with hot air to form a film and solidify, and then wound up after cooling.

[0068] Example 4

[0069] This embodiment provides a cleaning and passivation method for small-diameter, grooved, irregularly shaped copper wires, the method specifically including the following steps:

[0070] S1, the copper wire is pre-blown by an annular air knife to remove liquid and dust from its surface. The air supply pressure for the pre-blowing is 0.7MPa and the temperature is 35℃. A tee-shaped water guide pipe is introduced along the groove and arranged coaxially with the outer contour of the wire. The water guide pipe and the wire are fitted with a clearance of 0.7mm.

[0071] S2, when the copper wire passes through the guide water pipe, directional hot water flushing is performed in the same direction as the groove. During the directional hot water flushing, the hot water temperature is 70℃, the flushing pressure is provided by a high-pressure pump with a head of ≥30m, the single-stage flushing time is 0.12s, and the carbon dioxide concentration during the directional hot water flushing is 1200ppm. After the directional hot water flushing is completed, the section enters the brush section, the CO2 supply is stopped, catechin gel stock solution is added to the cleaning solution, and the brush is set up in conjunction with the synchronous spray cleaning solution for brushing. An annular air knife is used for inter-stage dehydration and isolation. The brush diameter is 110mm, the rotation speed is 550rpm, the brushing time is 6s, and the air supply pressure of the annular air knife is... The pressure was 0.7 MPa, the purging time was 4 s, and the preparation method of the catechin gel mother liquor was as follows: 85 g of 50 wt.% polyethyleneimine solution was mixed with 420 g of deionized water to obtain solution A; 7 g of dopamine hydrochloride was dissolved in 110 g of 0.01 M phosphate buffer solution with pH 7.4 and 0.9 g of sodium periodate was added for pre-oxidation for 0.06 h to obtain solution B; solution B was added dropwise to solution A and reacted for 2.2 h; the temperature was raised to 62 °C and 45 g of 35 wt.% sodium 3-chloro-2-hydroxypropanesulfonate solution was added and reacted for 6.5 h to obtain a zwitterionic solution; 16 g of polyacrylic acid was dissolved in 110 g of water and 9 g of EDC·HCl and 5 g of NHS were added for activation for 0.55 h to obtain activation solution; activation solution was added dropwise to zwitterionic solution and reacted for 6.5 h; dialyzed, concentrated, and filtered to obtain catechin gel mother liquor;

[0072] S3, the copper wire is introduced into the ultrasonic cleaning tank. The temperature of the liquid in the ultrasonic cleaning tank is 38℃ and the ultrasonic frequency is 36kHz. The wire is reciprocated by a multi-slot wire guide wheel. The diameter of a single multi-slot wire guide wheel is >400mm, the center distance between adjacent wire guide wheels is 1.8m, the number of wire guide slots is 7, and the equivalent dwell time of the reciprocating wire is 15s. An annular air knife is set at the end of the section for secondary dehydration and isolation.

[0073] S4. The copper wire is guided into a three-way hot air duct arranged in the same direction as the groove for deep dehydration and flow-guiding drying along the groove. In the three-way hot air duct, the temperature of the hot compressed air is 70℃, the air supply pressure is 0.7MPa, and the processing time is 0.13s. Then, it enters a passivation chamber equipped with an ultrasonic atomizer for atomization coverage. In the passivation chamber, the room temperature is 28℃, the median diameter D50 of the droplets is 0.4μm, the atomization time is 8s, and succinyl imidazole agent is added to the passivation solution to make the mass fraction of succinyl imidazole agent in the passivation solution 0.10wt.%, and the pH of the passivation solution is 6.4. The preparation method of the succinyl imidazole agent is as follows: 120g 1-(3-aminopropyl)imidazole was dispersed with 105g of succinic anhydride in 320g of acetone and reacted in an ice-water bath for 2.5h. Then, the mixture was stirred at room temperature for 7h. The mixture was distilled under reduced pressure to obtain a viscous substance. 550g of deionized water was added and stirred, and 35g of sodium hydroxide solution with a mass fraction of 30wt.% was added dropwise. The mixture was filtered and concentrated under reduced pressure to obtain succinylimidazole. A hot air knife was set at the outlet of the chamber for purging. The temperature of the hot air knife was 32℃, the air supply pressure was 0.7MPa, and the purging time was 4s.

[0074] S5, the copper wire is dried with hot air to form a film and solidify, and then wound up after cooling.

[0075] Comparative Example 1

[0076] This comparative example provides a cleaning and passivation method for small-diameter, grooved, irregularly shaped copper wires. The difference between this method and Example 1 is that no catechin gel mother liquor is added in S3, and no succinyl imidazole agent is added in S4. Other process parameters and operating conditions are exactly the same as in Example 1.

[0077] Comparative Example 2

[0078] This comparative example provides a cleaning and passivation method for small-diameter, grooved irregular copper wires. The difference between this method and Example 1 is that no catechin gel mother liquor is added in S3, while the other process parameters and operating conditions are exactly the same as in Example 1.

[0079] Comparative Example 3

[0080] This comparative example provides a cleaning and passivation method for small-diameter, grooved irregular copper wires. The difference between this method and Example 1 is that no succinyl imidazole agent is added in S4, while the other process parameters and operating conditions are exactly the same as in Example 1.

[0081] Surface cleanliness test method: Water film rupture test. The copper wire sample to be tested is vertically fixed on the test stand. Deionized water is sprayed evenly from the top of the sample and rinsed for 5 seconds to ensure that the surface is completely wetted. After rinsing stops, timing is started immediately, and the state of the water film on the sample surface is observed. The time required from the start of timing to the water film rupture and the first exposure of the discontinuous dry area is recorded as the water film rupture time t(s).

[0082] Corrosion resistance testing method: Electrochemical polarization curve testing was conducted on a CHI760E electrochemical workstation using a standard three-electrode system. The copper wire sample under test was used as the working electrode, a saturated calomel electrode (SCE) as the reference electrode, and a platinum sheet electrode as the counter electrode. The test electrolyte was a 3.5% (w / w) NaCl aqueous solution. The working area of ​​the working electrode was 1.0 cm². 2 The sample was immersed in an electrolyte solution, and after the open circuit potential (OCP) stabilized for 30 minutes, a potentiodynamic scan was performed at a scan rate of 1 mV / s, covering a range of -250 mV to +250 mV relative to the open circuit potential. The corrosion potential (V) and corrosion current density (A / cm²) of the sample were calculated by fitting the weak polarization region of the obtained Tafel polarization curve. 2 ).

[0083] The test results are shown in Table 1.

[0084] Table 1. Test results of the cleaning and passivation methods for small-diameter, grooved, irregularly shaped copper wires in Examples 1-4 and Comparative Examples 1-3.

[0085]

[0086] As shown in Table 1, compared to Example 1, Comparative Example 1 exhibits a reduced water film rupture time, a negative shift in corrosion potential, and an increased corrosion current density; Comparative Example 2 shows a reduced water film rupture time, a negative shift in corrosion potential, and an increased corrosion current density; and Comparative Example 3 shows a reduced water film rupture time, a negative shift in corrosion potential, and an increased corrosion current density. This is because in Comparative Example 1, relying solely on hot water and physical rinsing has limited effectiveness in removing stubborn oil and oxides, leaving a large number of low surface energy areas on the surface. Therefore, the water film ruptures rapidly, and the unclean surface cannot form an effective film layer, resulting in a negative shift in corrosion potential and an increased corrosion current density. In Comparative Example 2, without the addition of catechin gel stock solution, a small amount of contaminants remain on the wire surface. The unclean substrate surface (incomplete cleaning) leads to defects in the passivation film, thereby reducing the overall protective effect. In Comparative Example 3, without the addition of succinyl imidazole agent, the surface cleanliness is high due to the complete cleaning steps and the addition of catechin gel stock solution, resulting in good hydrophilicity and an almost unchanged water film rupture time. However, the lack of succinyl imidazole agent results in a lack of corrosion inhibition effect, leading to a negative shift in corrosion potential and an increased corrosion current density.

[0087] The above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A method for cleaning and passivating irregularly shaped copper wires with small diameter and grooves, characterized in that, The method includes: S1, the copper wire is pre-blown by an annular air knife to remove liquid and dust from its surface, and then introduced into a tee-shaped guide water pipe arranged coaxially with the outer contour of the wire. The guide water pipe and the wire are fitted with a clearance limit. S2, when the copper wire passes through the guide water pipe, directional hot water flushing is carried out in the same direction as the groove. CO2 is introduced at the same time as directional hot water flushing. After the directional hot water flushing is completed, the brush section is entered, the CO2 is stopped, catechin gel mother liquor is added to the cleaning solution, and the brush is set up to cooperate with the synchronous spray cleaning solution for brushing. The inter-section dehydration and isolation is carried out by an annular air knife. S3, copper wire is introduced into ultrasonic cleaning tank, and reciprocating wire is achieved by multi-slot wire guide wheel. At the end of the section, an annular air knife is set for secondary dehydration and isolation. S4. The copper wire is introduced into a three-way hot air duct arranged in the same direction as the groove for deep dehydration and flow drying along the groove. Then it enters the passivation chamber equipped with an ultrasonic atomizer for atomization and coverage. Succinyl imidazole agent is added to the passivation liquid. A hot air knife is set at the exit of the chamber for purging. S5, the copper wire is dried with hot air to form a film and solidify, and then wound up after cooling; The preparation method of the catechin gel mother liquor is as follows: Solution A is obtained by mixing polyethyleneimine solution with deionized water. Dopamine hydrochloride is dissolved in phosphate buffer solution and pre-oxidized with sodium periodate to obtain solution B. Solution B is added dropwise to solution A for reaction. Sodium 3-chloro-2-hydroxypropanesulfonate solution is added for reaction to obtain zwitterionic solution. Polyacrylic acid is dissolved in water and activated with EDC·HCl and NHS to obtain activation solution. Activation solution is added dropwise to zwitterionic solution for reaction. After dialysis, concentration and filtration, catechin gel mother liquor is obtained. The mass ratio of the polyethyleneimine solution, deionized water, dopamine hydrochloride, phosphate buffer solution, sodium periodate, sodium 3-chloro-2-hydroxypropanesulfonate solution, polyacrylic acid, water, EDC·HCl and NHS is (70-90):(350-450):(6-10):(80-120):(0.6-1):(30-56):(12-18):(80-120):(6-10):(3-6); The sodium 3-chloro-2-hydroxypropanesulfonate solution has a mass fraction of 20-45 wt.%. The preparation method of the succinyl imidazole agent is as follows: 1-(3-aminopropyl)imidazole was dispersed in acetone and reacted in an ice-water bath. The mixture was then stirred at room temperature and distilled under reduced pressure to obtain a viscous substance. Deionized water was added and stirred, and sodium hydroxide solution was added dropwise. The mixture was then filtered and concentrated under reduced pressure to obtain succinylimidazole.

2. The cleaning and passivation method for small-diameter, grooved, irregularly shaped copper wire according to claim 1, characterized in that, In S1: The pre-blowing air supply pressure is 0.5-0.8 MPa, and the temperature is 20-40℃; The clearance fit is 0.5-0.8mm.

3. The cleaning and passivation method for small-diameter, grooved, irregularly shaped copper wire according to claim 1, characterized in that, In S2: During the directional hot water flushing process, the hot water temperature is 60-75℃, the flushing pressure is provided by a high-pressure pump with a head of ≥30m, and the single-stage flushing time is 0.07-0.15s; The dissolved concentration of carbon dioxide during the directional hot water flushing process is 800-1500 ppm; The step involves adding catechin gel stock solution to the cleaning solution to achieve a solid content of 200-350 ppm and a pH of 7.8-8.

8.

4. The cleaning and passivation method for small-diameter, grooved, irregularly shaped copper wire according to claim 1, characterized in that, In S3: In the multi-groove wire guide wheel, the diameter of a single wheel is >400mm, the center distance between adjacent wire guide wheels is 1.5-2.5m, the number of wire guide grooves is 6-8, and the equivalent dwell time for reciprocating wire travel is 10-30s.

5. The cleaning and passivation method for small-diameter, grooved, irregularly shaped copper wire according to claim 1, characterized in that, In S4: In the three-way hot air duct, the temperature of the hot compressed air is 60-75℃, the air supply pressure is 0.5-0.8MPa, and the processing time is 0.07-0.15s; In the passivation chamber, the room temperature is 25-35℃, the median diameter D50 of the droplets is 0.1-0.5μm, and the atomization time is 3-10s.

6. The cleaning and passivation method for small-diameter, grooved, irregularly shaped copper wire according to claim 1, characterized in that, In S4: The step involves adding succinyl imidazole to the passivation solution, such that the mass fraction of succinyl imidazole in the passivation solution is 0.08-0.20 wt.%, and the pH of the passivation solution is 6.0-6.

6.

7. The cleaning and passivation method for small-diameter, grooved, irregularly shaped copper wire according to claim 1, characterized in that, The mass ratio of 1-(3-aminopropyl)imidazolium, succinic anhydride, acetone, deionized water and sodium hydroxide solution is (100-130):(90-110):(250-350):(400-600):(20-40).

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