Method for processing fine iron-nickel alloy wire

Abstract

This invention provides a method for processing fine iron-nickel alloy wire, comprising: pre-treating the wire to be processed using a first mold and a lubricant; drawing the pre-treated wire using a second mold set and a first lubricant; drawing the wire obtained after the first drawing process using a third mold set and a second lubricant; and a cleaning step: cleaning the wire obtained after the second drawing process. Pre-treatment effectively removes surface contaminants from the raw material; the first lubricant improves drawing efficiency and surface quality; the second lubricant removes residual first lubricant from the wire, giving the processed wire better washability; and cleaning makes the wire cleaner. Compared with existing technologies, no intermediate heat treatment is required, and fine iron-nickel alloy wire with good surface quality can be obtained through a simple process.

Description

Technical Field

[0001] This invention relates to the field of micro-alloy wire processing technology, and in particular to a method for processing micro-fine iron-nickel alloy wire. Background Technology

[0002] Micro-alloy wires are widely used in electrical and electronic, semiconductor, medical, and precision instrument fields. Common types of micro-alloy wires include titanium alloy wire, copper wire, and gold wire. For these micro-alloy wires with a diameter of no more than 200 micrometers, the main processing technology is wire drawing. Iron-nickel alloys with a nickel content between 36% and 42% have a low coefficient of thermal expansion and a constant elastic modulus, making them suitable for use as hairsprings in precision instruments and watches. As intermediate products, their minimum diameter is generally between 0.05mm and 0.2mm. These intermediate micro-alloy hairsprings, in addition to their extremely small size, also require high precision and surface quality, with very high requirements for alloy color, corrosion resistance, and surface adhesion.

[0003] In the process of drawing micro-iron-nickel alloy wires, lubrication measures are necessary to reduce the impact of frictional heat on the alloy's microstructure and properties, improve surface quality, and reduce drawing force. To achieve the required wire quality, existing micro-iron-nickel alloy wire drawing processes use soap flake aqueous solutions as drawing lubricants. However, soap flake aqueous solutions have poor lubrication effects, making it difficult to guarantee dimensional accuracy after drawing. Furthermore, soap flake aqueous solutions remain on the wire surface, easily causing the iron-nickel alloy to rust. Patent CN114480003B discloses a drawing lubricant, but this lubricant has high viscosity and poor adhesion to micro-wires, resulting in poor lubrication. It also presents challenges for subsequent cleaning. Patent CN111346941B discloses a multi-pass continuous drawing method for medical-grade stainless steel ultrafine wires. Through multiple online coating treatments, cold drawing, coating removal, and solution treatment processes, a bright surface medical-grade stainless steel ultrafine wire is obtained. However, this method is complex and energy-intensive.

[0004] Therefore, a new solution is needed. Summary of the Invention

[0005] The purpose of this invention is to address the problems of complex processing technology, low precision, and poor surface quality of micro-fine iron-nickel alloy wire in the existing technology, and to provide a simple, high-precision, and high-quality micro-fine iron-nickel alloy wire processing method.

[0006] According to one aspect of the present invention, a method for processing fine iron-nickel alloy wire is provided, comprising the following steps:

[0007] Pre-treatment steps: The wire to be treated is pre-treated using a first mold and a lubricant, wherein the first mold consists of an inlet area, a lubrication area, a peeling area, a first decompression area, a sizing area, a second decompression area, and an outlet area;

[0008] First drawing step: The pretreated wire is drawn using the second die set and the first lubricant. The second die set consists of n second dies. Each second die is composed of an inlet area, a lubrication area, a compression area, a sizing area, a decompression area, and an outlet area. The diameter of the sizing area of ​​the i-th second die is denoted as Di. Then, 1.05≤Di-1 / Di≤1.1, where i is a positive integer greater than 1 and less than or equal to n. The relationship between the diameter D1 of the sizing area of ​​the first second die and the diameter D0 of the sizing area of ​​the first die used for pretreatment is 1.05≤D0 / D1≤1.1.

[0009] The second drawing step: The wire obtained after the first drawing process is drawn using the third die group and the second lubricant. The third die group includes m third dies. Each third die consists of an inlet area, a lubrication area, a compression area, a sizing area, a decompression area, and an outlet area. The diameter of the sizing area of ​​the j-th third die is denoted as dj. Then, 1.02≤dj-1 / dj≤1.06, where j is a positive integer greater than 1 and less than or equal to m. The relationship between the diameter d1 of the sizing area of ​​the first third die and the diameter Dn of the sizing area of ​​the n-th second die is 1.02≤Dn / d1≤1.06.

[0010] Cleaning steps: Clean the filaments obtained after the second drawing process.

[0011] In the processing method provided by the present invention, the cone angle γ of the peeling zone is in the range of 40°-70°.

[0012] In the processing method provided by the present invention, in the pretreatment step, the lubricant includes at least one of paraffin wax and flake graphite, zinc oxide, and molybdenum sulfide, and the mass fraction of graphite, zinc oxide, and molybdenum sulfide in the lubricant is 2 to 10%.

[0013] In the processing method provided by the present invention, the core material of the second mold is polycrystalline diamond, and the second mold assembly is immersed in the first lubricating liquid.

[0014] In the processing method provided by the present invention, the first lubricant, by weight, comprises: 0.1-0.3% methyl silicone oil, 0.2-0.5% silica, 0.1-0.2% sodium tripolyphosphate, 3-8% additives, and the balance being cycloalkanes in mineral oil.

[0015] In the processing method provided by the present invention, the additive is one or more of graphite, zinc oxide, and molybdenum sulfide, and the additive is in the form of flakes with a thickness-to-diameter ratio ≤1:10 and an average particle size ≤100 nm.

[0016] In the processing method provided by the present invention, the core material of the third mold is single crystal diamond, and the lubrication between the third mold and the wire is provided by a second lubricating fluid, which is provided by spraying.

[0017] In the processing method provided by the present invention, the second lubricant comprises, by weight: 0.5-2% rapeseed oil, 2-5% fatty acid soap, 0.2-0.5% dimethylsiloxane, 0.2-0.5% sodium tripolyphosphate, and the balance being deionized water.

[0018] In the processing method provided by the present invention, the cleaning step is carried out by one or both of solution cleaning or plasma cleaning.

[0019] In the processing method provided by this invention, a hydrocarbon cleaning agent is used in the solution cleaning; in the plasma cleaning, one or more of air, argon, and helium are used, the gas pressure is 0.2-0.5 MPa, and the plasma power is 50-200 W.

[0020] This invention has at least the following beneficial effects: Before drawing, the peeling process using the first mold in the pretreatment step effectively removes surface dirt from the raw materials, offering advantages in efficiency and environmental friendliness compared to the acid washing method used in existing technologies; regarding drawing lubrication, compared to the poor lubrication effect and easy rusting problems associated with soap water lubrication in existing technologies, the first lubricant of this invention has a better lubrication effect, improving drawing efficiency and surface quality, and solving the problem of easy rusting of existing wire materials; the second lubricant of this invention has excellent defoaming effect and low viscosity, allowing for good adhesion to fine wires, providing excellent lubrication, and also removing… The residual lubricant on the filaments improves their cleanability after processing. In terms of the drawing process, the filaments exhibit higher dimensional accuracy, controllable within 0.3μm, while existing technologies typically only achieve 0.5μm. Furthermore, compared to existing technologies, no intermediate heat treatment is required, simplifying the process. The cleaning process employed in this invention is more environmentally friendly than existing technologies. As a preferred option, hydrocarbon cleaning agents and plasma cleaning are used. The hydrocarbon cleaning agents dissolve and remove the lubricant from the filament surface, accelerating moisture evaporation. Plasma cleaning decomposes residual C, H, O, and other trace elements on the filament surface, resulting in cleaner filaments and a better cleaning effect. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort:

[0022] Figure 1 The diagram shows a flowchart of a processing method for fine iron-nickel alloy wire according to an embodiment of the present invention;

[0023] Figure 2 The image shown is a cross-sectional view of the first mold used in the pretreatment step of an embodiment of the present invention.

[0024] Figure 3 The image shown is a cross-sectional view of the second mold used in an embodiment of the present invention;

[0025] Figure 4 The image shows the surface of the wire processed according to Example 3;

[0026] Figure 5 The image shows the surface of a wire processed using existing techniques. Detailed Implementation

[0027] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Typical embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0029] Figure 1 The diagram shows a flowchart of a method for processing micro-fine iron-nickel alloy wire according to an embodiment of the present invention. Figure 1 As shown, the processing method for fine iron-nickel alloy wire provided by the present invention includes the following steps:

[0030] S1. Pretreatment steps: Use the first mold and lubricant to pretreat the wire material to be treated.

[0031] Specifically, in one embodiment of the present invention, such as Figure 2As shown, the first die consists of an inlet area 1, a lubrication area 2, a peeling area 3, a first decompression area 4, a sizing area 5, a second decompression area 6, and an outlet area 7, wherein the diameter of the sizing area 5 is D0. The inlet area 1 provides a smooth profile for the wire to reach the lubrication area, allowing the lubricant to reach the working surface of the drawing die. The lubrication area 2 stores the lubricant and inputs it into the working area. The peeling area 3 removes dirt and rust from the surface of the raw wire, improving the surface quality of the wire and reducing the chance of dirt entering the lubricant. The first decompression area 4 reduces stress concentration on the wire after passing through the peeling area, minimizing surface damage. The sizing area 5 controls the die aperture size; the metal wire passes through this area to obtain its final size. The second decompression area 6 prevents damage to the wire from stress concentration at the intersection points caused by the recovery of elastic deformation when moving from the sizing area to the outlet area, or damage to the wire surface. The outlet area 7 ensures that the compression area is in the center of the die core thickness, giving the die core the best anti-expansion strength.

[0032] Furthermore, in one embodiment of the present invention, the cone angle γ of the peeling zone is in the range of 40°-70°, which can achieve a better peeling effect. If the cone angle of the peeling zone is further increased, the contact area between the mold and the wire is too smooth, and the peeling effect is not obvious; if the cone angle of the peeling zone is too small, it is easy to cause stress concentration at the contact area between the wire and the mold, and at the same time, the wire drawing resistance is large, which can easily lead to wire breakage.

[0033] Furthermore, in one embodiment of the present invention, to further improve the peeling effect, a lubricant is added between the first mold and the filament. The lubricant is a mixture comprising at least one of paraffin wax and flake graphite, zinc oxide, and molybdenum sulfide. By mass fraction, graphite, zinc oxide, and molybdenum sulfide account for 2-10% of the mixture. During use, the lubricant is extruded into the inlet area at a temperature of 80-140°C and carried into the lubrication zone with the filament, effectively reducing the resistance in the peeling zone. Simultaneously, the additives in the paraffin wax—flake graphite, zinc oxide, and molybdenum sulfide—further enhance the peeling lubrication effect, reduce peeling resistance, and decrease heat generation, which is beneficial for the formation of a good surface quality in the filament.

[0034] S2, First drawing step: The pre-treated wire is drawn using the second mold set and the first lubricant.

[0035] Specifically, in one embodiment of the present invention, the second mold group comprises n (e.g., 24) second molds, each with a core material of polycrystalline diamond. In use, each mold is mounted on a mold slot of a single-head (when n is 1) or multi-head wire drawing machine. After the first wire drawing process of the present invention, the wire diameter is not less than 0.2 mm. Specifically, in one embodiment of the present invention, as... Figure 3As shown, each second mold consists of an inlet area 11, a lubrication area 12, a compression area 13, a sizing area 14, a decompression area 15, and an outlet area 16. The diameter of the sizing area of ​​the i-th second mold is denoted as Di, where 1.05 ≤ Di-1 / Di ≤ 1.1, and i is a positive integer greater than 1 and less than or equal to n. The relationship between the diameter D1 of the sizing area of ​​the first second mold and the diameter D0 of the sizing area of ​​the first mold used for pretreatment is 1.05 ≤ D0 / D1 ≤ 1.1. The inlet zone 11 provides a smooth profile for the wire to reach the lubrication zone, allowing the lubricant to reach the working surface of the drawing die. The lubrication zone 12 stores the lubricant and introduces it into the working zone. The compression zone 13 compresses the wire, causing it to deform from large to small. The sizing zone 14 controls the die aperture size, through which the metal wire obtains its final dimensions. The decompression zone 15 prevents the wire from being damaged by stress concentration at the intersection due to the recovery of elastic deformation of the metal as it moves from the sizing zone to the exit zone, or damage to the wire surface. The exit zone 16 ensures that the compression zone is located in the center of the die core thickness, giving the die core the best anti-expansion strength.

[0036] Furthermore, in one embodiment of the invention, the molds of the second mold group are immersed in the first lubricating fluid. The filament passes sequentially through each mold of the second mold group in the first lubricating fluid. Immersion provides full-coverage lubrication for the filament during the first drawing process. Compared to spray lubrication, immersion allows for more thorough contact between the lubricating fluid and the filament and the second mold, resulting in a larger contact area and a more ideal lubrication effect. It avoids the lubricating fluid being flung out during the drawing process as is seen in spray lubrication. Moreover, immersion lubrication allows the frictional heat generated during the drawing process to be carried away by the first lubricating fluid more quickly.

[0037] Furthermore, in one embodiment of the present invention, the first lubricant comprises: 0.1-0.3% methyl silicone oil, 0.2-0.5% silica, 0.1-0.2% sodium tripolyphosphate, 3-8% additives, and the balance being cycloalkanes in mineral oil. The additives are one or more of graphite, zinc oxide, and molybdenum sulfide, and are in flake form with a thickness-to-diameter ratio not exceeding 1:10 and an average particle size ≤100 nm.

[0038] In existing technologies, rusting of iron-nickel alloys mainly occurs upon contact with water and oxygen in the lubricating fluid, resulting in the formation of iron oxides. In this technical solution, the main component of the first lubricating fluid is cycloalkanes-based mineral oil, which is water-free, thus preventing rusting of the wire. Methyl silicone oil is soluble in mineral oil and has low surface tension and high compressibility. In this invention, the surface tension characteristics of methyl silicone oil are utilized to effectively defoam, preventing the formation of bubbles in the first lubricant due to cavitation during wire movement and friction between the wire and the die. Furthermore, the deformation of the wire in the die is a compression process, and the compressibility of methyl silicone oil reduces the degradation of the first lubricating fluid. Graphite, zinc oxide, and molybdenum sulfide are generally solid particles at room temperature and can function as lubricants in existing industrial technologies; however, irregularly shaped particles can damage the smooth surface of the wire. Simultaneously, if these solid particles enter the sizing zone between the wire and the die, they can affect the dimensional accuracy of the wire. This invention employs an additive that is one or more of graphite, zinc oxide, and molybdenum sulfide. The additive is flake-shaped, with a thickness-to-diameter ratio not exceeding 1:10 and an average particle size ≤100 nm. This flake-shaped additive has a larger specific surface area and a smaller thickness-to-diameter ratio than conventional particles. When the filament enters the die for extrusion deformation, the flake-shaped additive mixed in the first lubricant forms a mixed oil film under extrusion pressure. Under pressure, the additive automatically selects a favorable direction—the thickness direction perpendicular to the filament diameter—to enter the die, providing better coating of the filament, thereby enhancing lubrication and effectively avoiding scratches on the filament surface caused by additives in existing technologies. Furthermore, the smaller size of the additive in the thickness direction reduces its impact on the precision of the filament.

[0039] Furthermore, compared to water-based lubricants in the prior art, cycloalkane-based mineral oils have a higher viscosity, and the viscosity increases further with the addition of additives, increasing the resistance of the filament during movement. In addition, the dispersion effect of solid additives in cycloalkane-based mineral oils is also an important factor in lubrication performance, especially in additive formulations with different densities, where this effect is crucial. The first lubricant of this invention contains silica and sodium tripolyphosphate. Silica has good fluidity; when mixed in the first lubricant, it promotes the flow of the first lubricant during the drawing motion and the rotation of the drawing machine's rollers, increasing the uniform distribution of the additives in the first lubricant. Sodium tripolyphosphate has a combined effect of suspension and dispersion, further promoting the uniform distribution of the additives in the first lubricant.

[0040] S3, Second drawing step: The wire obtained after the first drawing process is drawn using the third mold group and the second lubricant.

[0041] Specifically, in one embodiment of the present invention, the third mold group includes m (e.g., 24) third molds. The third molds have the same structure as the second molds, that is, each third mold consists of an inlet area, a lubrication area, a compression area, a sizing area, a decompression area, and an outlet area. The diameter of the sizing area of ​​the j-th third mold is denoted as dj. Then, 1.02≤dj-1 / dj≤1.06, where j is a positive integer greater than 1 and less than or equal to m. The relationship between the diameter d1 of the sizing area of ​​the first third mold and the diameter Dn of the sizing area of ​​the n-th second mold is 1.02≤Dn / d1≤1.06.

[0042] Furthermore, the core material of each mold in the third mold group is single-crystal diamond, and the lubrication between the mold and the wire is provided by a second lubricant, which is provided by spraying. The components of the second lubricant include: 0.5-2% rapeseed oil, 2-5% fatty acid soap, 0.2-0.5% dimethylsiloxane, 0.2-0.5% sodium tripolyphosphate, and the balance being deionized water.

[0043] After the first drawing process, the diameter of the filament decreases further. When using a high-viscosity oil-based lubricant or immersion lubrication, the movement of the filament and the rotation of the roller create cavities around the filament, preventing the formation of a lubricating film on the finer, moving filament. This results in poor lubrication and increases the risk of filament breakage during drawing. The second lubricant in this invention is water-based, with a lower viscosity than oil-based lubricants. The pressure applied during spraying effectively removes residual first lubricant from the filament, increasing the adhesion of the second lubricant and improving the lubrication effect.

[0044] This invention selects fatty acid soap as the main component of the second lubricant, which has the highest content besides deionized water. This is because fatty acid soap has good lubricating properties, is soluble in water, and does not easily produce soap bubbles, thus improving the lubrication effect. The fatty acid soap aqueous solution can also dissolve the main component of the first lubricant—mineral oil—residual on the silk to a certain extent, thereby reducing the difficulty of subsequent cleaning.

[0045] Furthermore, to address the problem of easy rust corrosion of existing wire materials, the second lubricant of this invention contains 0.5-2% rapeseed oil. In this invention, the main function of rapeseed oil is to form a rust-preventive protective film on the surface of the wire material; at the same time, rapeseed oil also has a certain lubricating effect.

[0046] Furthermore, the sodium tripolyphosphate aqueous solution is weakly alkaline. In this invention, sodium tripolyphosphate serves to adjust the pH value of the second lubricating fluid. In addition, sodium tripolyphosphate promotes the dissolution of fatty acid soaps in water and stabilizes the properties of the fatty acid soap aqueous solution. Dimethylsiloxane is a good surfactant. In this invention, dimethylsiloxane can reduce the surface tension of the lubricating film on the filament, resulting in better adhesion and promoting the formation of the lubricating oil film.

[0047] After this process, the lubricant remaining on the wire is mainly the second lubricant, which has excellent cleanability.

[0048] S4. Cleaning step: Clean the filaments obtained after the second drawing process.

[0049] Specifically, in one embodiment of the present invention, the cleaning step is performed by one or both of solution cleaning and plasma cleaning. In solution cleaning, the solution is composed of a hydrocarbon cleaning agent, which has good oil-dissolving, decontamination, and rapid drying capabilities, thus facilitating the obtaining of clean silk materials. In plasma cleaning, one or more of air, argon, and helium are used, with a gas pressure of 0.2-0.5 MPa and a plasma power of 50-200 W. Plasma cleaning can break the chemical bonds on the surface of the silk material, causing contaminants to vaporize and detach from the silk material surface within the parameter range of the present invention.

[0050] Furthermore, in one embodiment of the present invention, the cleaning is a combined cleaning of solution cleaning and plasma cleaning. Plasma cleaning following hydrocarbon cleaning can promote the volatilization of the hydrocarbon cleaning agent and decompose and vaporize the trace amounts of stubborn stains remaining on the filament, resulting in a better cleaning effect.

[0051] Compared with the prior art, the present invention has the following technical advantages:

[0052] (1) Before drawing, the peeling process is carried out by the first mold in the pretreatment step, which can effectively remove dirt from the surface of the raw materials. Compared with the acid washing method in the existing technology, it has the advantages of high efficiency and environmental protection.

[0053] (2) In terms of wire drawing lubrication, compared with the problems of poor lubrication effect and easy rusting caused by existing technology using soap water lubrication, the first lubricant of the present invention has a better lubrication effect, which can improve wire drawing efficiency and surface quality, and solve the problem of easy rusting of existing wire materials; the second lubricant of the present invention has a good defoaming effect and low viscosity, which can achieve good adhesion on fine wires, play a good lubrication effect, and can also remove the first lubricant residue on the wire material, so that the processed wire material has better washability;

[0054] (3) In terms of wire drawing process, the wire material has higher dimensional accuracy that can be controlled within 0.3μm, while the dimensional accuracy of existing technology can generally only reach 0.5μm; and compared with existing technology, no intermediate heat treatment is required, and the process is simple.

[0055] (4) The cleaning process used in this invention is more environmentally friendly than the prior art. As a preferred solution, hydrocarbon cleaning agent and plasma cleaning are used. The hydrocarbon cleaning agent can dissolve and remove the lubricant on the surface of the silk material and accelerate the evaporation of water. The plasma cleaning can decompose the trace elements such as C, H and O remaining on the surface of the silk material, making the silk material cleaner and having a better cleaning effect.

[0056] The present invention will be further described below with reference to specific embodiments.

[0057] Implementation Example 1

[0058] S1. Pre-treatment step: A 0.6 mm diameter filament is passed through a first mold for pre-treatment. The diameter of the sizing zone of the first mold is 0.588 mm, and the cone angle γ of the peeling zone is 40°. A lubricant is added between the first mold and the filament. The lubricant is a mixture comprising paraffin wax and flake graphite. By mass fraction, graphite accounts for 2% of the mixture.

[0059] S2, First drawing step: The filament obtained in S1 is drawn through the second mold group.

[0060] The core material of the second mold group is polycrystalline diamond. All molds are immersed in lubricating fluid to ensure sufficient lubrication of the molds and wires. The lubricating fluid composition, by mass percentage, includes 0.3% methyl silicone oil, 0.25% silica, 0.1% sodium tripolyphosphate, 6% additives, and the balance being cycloalkanes in mineral oil. In this embodiment, the additive is flake graphite with a thickness-to-diameter ratio of 1:5 to 1:8 and an average particle size ≤20 nm.

[0061] The second die set contains 14 dies. Each die is arranged in descending order of its sizing zone diameter, and the wire passes through the second die in sequence. The sizing zone diameter of the i-th second die is denoted as Di, and Di-1 / Di = 1.05. After passing through the second die set, the wire diameter is 0.297 mm.

[0062] S3, Second drawing step: The filament obtained in S2 is drawn through the third mold group.

[0063] The core of the third mold assembly is made of single-crystal diamond. Lubrication between the mold and the wire is provided by a second lubricant, which is applied via spraying. In this embodiment, the second lubricant comprises, by mass percentage, 2% rapeseed oil, 3% fatty acid soap, 0.2% dimethylsiloxane, 0.5% sodium tripolyphosphate, and the remainder being deionized water.

[0064] The third die set contains 24 dies. Each die is arranged in descending order of diameter in the sizing zone, and the wire passes through the dies accordingly. The diameter of the sizing zone in the third die set is dj, so dj-1 / dj=1.02. After passing through the third die set, the wire diameter is 0.091mm.

[0065] S4. Cleaning Steps: Clean the filaments obtained in S3.

[0066] The cleaning process begins in a hydrocarbon cleaning agent, allowing the filament to pass through a soft chuck immersed in the hydrocarbon cleaning agent at a uniform speed. Then, it passes through a plasma cleaner, which uses argon gas at a pressure of 0.2 MPa and a plasma power of 50 W.

[0067] Cleaned filaments can be used to make watch hairsprings.

[0068] Implementation Example 2

[0069] Unlike Example 1, the peeling zone cone angle γ of the first mold is 50°. A lubricant is added between the first mold and the wire. The lubricant is a mixture comprising paraffin wax, zinc oxide, and molybdenum sulfide. By mass fraction, zinc oxide and molybdenum sulfide account for 2% and 4% of the mixture, respectively.

[0070] The second mold group has 10 molds, and Di-1 / Di=1.1. After passing through the second mold group, the wire diameter is 0.187mm.

[0071] The first lubricant consists of: 0.3% methyl silicone oil, 0.25% silica, 0.1% sodium tripolyphosphate, 3% additives, and the balance being cycloalkanes in mineral oil. The additive is flake-shaped zinc oxide with a thickness-to-diameter ratio of 1:5 to 1:8 and an average particle size ≤20 nm.

[0072] The third mold group has one mold, and after passing through the third mold group, the wire diameter is 0.179 mm.

[0073] The second lubricant consists of: 0.5% rapeseed oil, 2% fatty acid soap, 0.2% dimethylsiloxane, 0.2% sodium tripolyphosphate, and the remainder is deionized water.

[0074] The cleaning process begins in a hydrocarbon cleaning agent, followed by a plasma cleaning machine. The plasma cleaning machine uses air at a pressure of 0.5 MPa and a plasma power of 200 W.

[0075] Implementation Example 3

[0076] Unlike Example 2, the peeling zone cone angle γ of the first mold is 60°. A lubricant is added between the first mold and the wire. The lubricant is a mixture comprising paraffin wax and molybdenum sulfide. By mass fraction, molybdenum sulfide accounts for 10% of the mixture.

[0077] The second die set has 10 dies, and Di-1 / Di=1.07. After passing through the second die set, the wire diameter is 0.261 mm.

[0078] The first lubricant comprises: 0.2% methyl silicone oil, 0.2% silica, 0.2% sodium tripolyphosphate, 8% additives, and the balance being cycloalkanes in mineral oil. The additives are a mixture of flake graphite and molybdenum sulfide in a mass ratio of 1:3, with a thickness-to-diameter ratio of 1:5 to 1:10 and an average particle size ≤70 nm.

[0079] The third mold group has 12 molds, and after passing through the third mold group, the wire diameter is 0.167 mm.

[0080] The second lubricant consists of: 0.5% rapeseed oil, 2% fatty acid soap, 0.2% dimethylsiloxane, 0.2% sodium tripolyphosphate, and the remainder is deionized water.

[0081] The cleaning process involves a plasma cleaner that uses air and helium in a 5:1 ratio, with a gas pressure of 0.3 MPa and a plasma power of 60-80 W.

[0082] Implementation Example 4

[0083] Unlike Example 3, the cone angle γ of the peeling area of ​​the first mold is 70°.

[0084] The second mold set has 1 mold, and Di-1 / Di=1.1. After passing through the second mold set, the wire diameter is 0.535mm.

[0085] The first lubricant comprises: 0.2% methyl silicone oil, 0.3% silica, 0.2% sodium tripolyphosphate, 5% additives, and the balance being cycloalkanes in mineral oil. The additive is flake-shaped molybdenum sulfide with a thickness-to-diameter ratio of 1:7 to 1:10 and an average particle size ≤100 nm.

[0086] The third mold group has 20 molds, and after passing through the third mold group, the wire diameter is 0.2 mm.

[0087] The second lubricant consists of: 1% rapeseed oil, 5% fatty acid soap, 0.3% dimethylsiloxane, 0.2% sodium tripolyphosphate, and the remainder is deionized water.

[0088] The cleaning method is hydrocarbon cleaning agent.

[0089] Implementation Example 5

[0090] Unlike Example 1, the diameter dj-1 of the sizing zone of the third die set has the following relationship with dj: dj-1 / dj=1.045. After passing through the third die set, the wire diameter is 0.05 mm.

[0091] In the above implementation examples, the final wire diameter tolerance is within 0.5μm. Figure 4 This is the surface effect of the filament treated by the method in Example 3, and... Figure 4 The comparison with existing technologies shown demonstrates that by using the processing method of the present invention, the surface of the wire is bright, free of rust, and free of any adhering substances.

[0092] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A method for processing a fine iron-nickel alloy wire, characterized by, Includes the following steps: Pre-treatment steps: The wire to be treated is pre-treated using a first mold and a lubricant. The first mold consists of an inlet area, a lubrication area, a peeling area, a first decompression area, a sizing area, a second decompression area, and an outlet area. The cone angle γ of the peeling area is in the range of 40°-70°. The first drawing step: The pretreated wire is drawn using the second die set and the first lubricant. The second die set consists of n second dies, each of which comprises an inlet area, a lubrication area, a compression area, a sizing area, a decompression area, and an outlet area. The diameter of the sizing area of ​​the i-th second die is denoted as Di, where 1.05 ≤ Di-1 / Di ≤ 1.1, and i is a positive integer greater than 1 and less than or equal to n. The diameter D1 of the sizing area of ​​the first second die is equal to the diameter D0 of the sizing area of ​​the first die used for pretreatment. The relationship is 1.05≤D0 / D1≤1.

1. The second mold assembly is immersed in the first lubricant. By weight, the first lubricant comprises: 0.1-0.3% methyl silicone oil, 0.2-0.5% silica, 0.1-0.2% sodium tripolyphosphate, 3-8% additives, and the balance being cycloalkanes in mineral oil. The additives are one or more of graphite, zinc oxide, and molybdenum sulfide. The additives are flaky, with a thickness-to-diameter ratio ≤1:10 and an average particle size ≤100nm. The second drawing step involves drawing the filament obtained from the first drawing process using a third die set and a second lubricant. The third die set comprises m dies, each consisting of an inlet area, a lubrication area, a compression area, a sizing area, a decompression area, and an outlet area. The diameter of the sizing area of ​​the j-th third die is denoted as dj, where 1.02 ≤ dj-1 / dj ≤ 1.06, and j is a positive integer greater than 1 and less than or equal to m. The relationship between the diameter d1 of the sizing area of ​​the first third die and the diameter Dn of the sizing area of ​​the n-th second die is 1.02 ≤ Dn / d1 ≤ 1.

06. Lubrication between the third dies and the filament is provided by the second lubricant, which is applied by spraying. By weight, the second lubricant comprises: 0.5-2% rapeseed oil, 2-5% fatty acid soap, 0.2-0.5% dimethylsiloxane, 0.2-0.5% sodium tripolyphosphate, and the remainder is deionized water. Cleaning steps: Clean the filaments obtained after the second drawing process.

2. The method of claim 1, wherein, In the pretreatment step, the lubricant includes at least one of paraffin wax and flake graphite, zinc oxide, and molybdenum sulfide, and the mass fraction of graphite, zinc oxide, and molybdenum sulfide in the lubricant is 2 to 10%.

3. The processing method according to claim 1, characterized in that, The core material of the second mold is polycrystalline diamond.

4. The processing method according to claim 1, characterized in that, The core material of the third mold is single-crystal diamond.

5. The processing method according to claim 1, characterized in that, The cleaning process can be carried out by one or both of solution cleaning and plasma cleaning.

6. The processing method according to claim 5, characterized in that, In solution cleaning, hydrocarbon cleaning agents are used; in plasma cleaning, one or more of air, argon, and helium are used, with a gas pressure of 0.2-0.5 MPa and a plasma power of 50-200 W.

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