Ultra-fine alloy wire for automobile and preparation method thereof

Abstract

The present invention relates to the technical field of automotive wires, and in particular to an ultra-fine alloy wire for automobiles and a preparation method thereof, comprising: obtaining a plurality of aluminum wires and a steel core wire; electroplating a copper layer on the steel core wire to obtain a copper-clad steel wire, determining whether a drawing process of the copper-clad steel wire is stable based on wire diameter fluctuations; and determining whether steel components penetrate into the copper layer based on the copper content or iron content of scraps; adjusting current density based on a ratio or determining whether the electroplating process is qualified based on the uniformity of the coating distribution of the copper-clad steel wire after drawing; twisting multiple groups of copper-clad aluminum wires by a wire bundler and wrapping them around the outside of the copper-clad steel wire to form a circular conductor structure; determining whether the twisting and wrapping process is qualified based on a composite morphology index, so as to adjust the production speed or stretching tension according to the relative difference; and wrapping polyvinyl chloride, cross-linked polyethylene, and fluoroplastics around the outside of the circular conductor structure by an extruder to obtain an insulating layer. The present invention improves the structural stability of the ultra-fine alloy wire for automobiles.

Description

Technical Field

[0001] The present invention relates to the technical field of automobile wires, and in particular to an extremely fine alloy wire for automobiles and a preparation method thereof. Background Art

[0002] With the rapid development of the automotive industry, especially the popularity of electric and hybrid vehicles, the requirements for wires are increasing. In automotive circuits, ultra-fine alloy wires have become an ideal alternative to traditional wires due to their excellent conductivity, high strength, and good corrosion resistance. However, the preparation of ultra-fine alloy wires faces many challenges, such as the stability of the wire drawing process, the quality of the electroplating layer, and the uniformity of the twisted coating. In particular, during the wire drawing and electroplating processes, due to the limitations of material properties and process parameters, it is difficult to achieve stable wire drawing and high-quality electroplating layers. This not only affects the performance of the wires, but also increases production costs and the difficulty of quality control.

[0003] Chinese patent application publication number CN118866475A discloses a process for preparing high-voltage cables for new energy vehicles. The process includes the following steps: Step 1: Raw material preparation: Placing the required metal conductor on a pay-off rack; Step 2: Wire drawing: Starting the wire drawing machine and gradually drawing the thick metal conductor through a die to achieve the required wire diameter; Step 3: Twisting the wires; Step 4: Insulation extrusion; Step 5: Cabling; Step 6: Rewinding. The twisted cables are positioned and guided by a traction assembly, causing multiple cores to gather inside the traction assembly to facilitate twisting into a cable. Simultaneously, the traction assembly and the rewinding assembly rotate in opposite directions, rubbing the cable surface with the traction assembly to remove burrs, protrusions, or uneven areas on the cable surface. The friction thickness can also be adjusted, making it suitable for cables of different materials. However, the prior art suffers from the following problems: During the wire drawing process, the prior art lacks monitoring and precise control of the wire drawing process, resulting in low wire drawing process stability, which in turn leads to low structural stability of the ultra-fine alloy wires used in automobiles. Summary of the Invention

[0004] To this end, the present invention provides an ultra-fine alloy wire for automobiles and a preparation method thereof, so as to overcome the problem that the prior art lacks monitoring and precise control of the wire drawing process, resulting in low stability of the wire drawing process and thus low structural stability of the ultra-fine alloy wire for automobiles.

[0005] To achieve the above object, the present invention provides a method for preparing ultra-fine alloy wire for automobiles, comprising:

[0006] Obtain some aluminum wire and steel core wire;

[0007] electroplating a copper layer on the steel core wire to obtain a copper-clad steel wire, drawing the copper-clad steel wire through a wire drawing machine, and determining whether the copper-clad steel wire drawing process is stable based on the wire diameter fluctuation of the copper-clad steel wire;

[0008] Collecting scrapings from the surface of the copper-clad steel wire when the wire drawing process is unstable, and determining whether there is steel component penetration inside the copper layer based on the copper content or iron content of the scrapings;

[0009] Under the condition that the presence of steel component penetration is determined, the current density is adjusted based on the ratio of the copper content to the preset copper content, or the plating distribution uniformity of the copper-clad steel wire after drawing is determined to be qualified;

[0010] Electroplating a copper layer on the aluminum wire to obtain a copper-clad aluminum wire, twisting a plurality of groups of the copper-clad aluminum wires by a wire bundling machine and wrapping them around the copper-clad steel wire that is stable during the wire drawing process to form a circular conductor structure;

[0011] determining whether the twisting and coating process is qualified based on the composite shape index of the circular conductor structure, so as to adjust the production speed or the stretching tension according to the relative difference between the composite shape index and the preset composite shape index;

[0012] Polyvinyl chloride, cross-linked polyethylene and fluoroplastic are coated on the outside of the circular conductor structure through an extruder to obtain an insulation layer.

[0013] Furthermore, based on the comparison result that the wire diameter fluctuation of the copper-clad steel wire during the drawing process is greater than the preset wire diameter fluctuation, it is determined that the copper-clad steel wire drawing process is unstable, and based on the comparison result that the copper content of the scrapings under the first layer detection method is greater than or equal to the preset copper content, it is determined that steel component penetration exists in the copper layer;

[0014] Among them, the first layer detection method is to scrape the surface copper layer from several sampling points to a depth of 50% of the copper layer thickness, collect the scrapings from each sampling point and detect whether they contain steel.

[0015] Furthermore, under the condition that steel components are infiltrated into the copper layer, the process of adjusting the current density includes:

[0016] dividing the copper content by a preset copper content;

[0017] Set a number of adjustment coefficients corresponding to the corresponding ratios;

[0018] increasing the current density of electroplating based on a number of the adjustment factors;

[0019] The corresponding relationship between the corresponding ratio and the increase in the current density of the electroplating is set to adjust the current density.

[0020] Furthermore, based on the comparison result that the wire diameter fluctuation of the copper-clad steel wire during the drawing process is greater than the preset wire diameter fluctuation, it is determined that the copper-clad steel wire drawing process is unstable, and based on the comparison result that the iron content of the scrapings under the second layer detection method is greater than or equal to the preset iron content, it is determined that steel components have penetrated into the copper layer;

[0021] The second-layer detection method is to scrape the copper layer from several sampling points until the steel core wire is just exposed, collect the scrapings from each sampling point and detect whether they contain steel.

[0022] Furthermore, based on the comparison result that the coating distribution uniformity of the copper-clad steel wire after drawing is less than or equal to a preset coating distribution uniformity, it is determined that the electroplating process is unqualified.

[0023] Furthermore, under the condition that the electroplating process is determined to be unqualified, the process of adjusting the electroplating temperature or stirring speed of the electroplating process includes:

[0024] Taking the absolute value of the difference between the coating distribution uniformity and the preset coating distribution uniformity;

[0025] Determining to increase the stirring speed by a preset stirring speed adjustment coefficient based on the comparison result that the absolute difference is less than or equal to the preset absolute difference;

[0026] Based on the comparison result that the absolute difference is greater than the preset absolute difference, it is determined to increase the electroplating temperature by a preset electroplating temperature adjustment coefficient.

[0027] Furthermore, based on the comparison result that the coating distribution uniformity of the copper-clad steel wire after drawing is less than or equal to the preset coating distribution uniformity, it is determined that the electroplating process is qualified but the wire drawing process is unqualified.

[0028] Furthermore, under the condition that it is determined that the electroplating process is qualified but the wire drawing process is unqualified, the process of adjusting the wire drawing machine parameters includes:

[0029] Subtracting the coating distribution uniformity from the preset coating distribution uniformity;

[0030] Determining, based on the comparison result that the difference is less than or equal to the preset difference, to reduce the drawing speed of the wire drawing machine by a first preset drawing speed adjustment coefficient;

[0031] Based on the comparison result that the difference is greater than the preset difference, it is determined that the drawing speed of the wire drawing machine is reduced by a second preset drawing speed adjustment coefficient.

[0032] Furthermore, based on the comparison result that the composite morphology index of the circular conductor structure is less than or equal to the composite morphology index threshold, it is determined that the composite morphology index threshold is less than or equal to the composite morphology index threshold, and according to the comparison result of the relative difference between the composite morphology index threshold and the composite morphology index and the preset relative difference, it is determined to increase the production speed of the wire bundling machine by the preset production speed adjustment coefficient or to reduce the tensile tension of the wire drawing machine by the preset tensile tension adjustment coefficient.

[0033] In another aspect, the present invention further provides an ultra-fine alloy wire for automobiles, comprising:

[0034] Copper-clad steel wire, which is used as a conductor to transmit electrical energy;

[0035] Copper-clad aluminum wire, which is coated on the outside of the copper-clad steel wire to protect the copper-clad steel wire;

[0036] The insulating layer is coated on the outside of the copper-clad aluminum wire to provide electrical isolation for the alloy wire.

[0037] Compared with the prior art, the beneficial effect of the present invention is that, by monitoring the stability of the copper-clad steel wire drawing process, the present invention can timely discover and solve the problem of wire diameter fluctuation caused by unstable drawing, thereby ensuring the quality of the copper-clad steel wire. By collecting scrapings from the surface of the copper-clad steel wire when the drawing process is unstable, and analyzing whether there is steel component penetration inside the copper layer, the purity and performance of the material are guaranteed, and a more reliable conductive foundation is provided for the wire. After the copper layer is electroplated on the aluminum wire to obtain the copper-clad aluminum wire, it is twisted and wrapped around the outside of the copper-clad steel wire with stable drawing to form a circular conductor structure. By monitoring the composite morphology index of the circular conductor structure, the qualification of the twisting and wrapping process is accurately evaluated, and the production speed or stretching tension is adjusted according to the evaluation results to optimize the compactness and uniformity of the conductor structure, thereby improving the mechanical strength of the wire and ensuring the stability of current transmission, thereby improving the structural stability of the ultra-fine alloy wire for automobiles.

[0038] Furthermore, the present invention determines the wire drawing stability by monitoring the wire diameter fluctuation during the copper-clad steel wire drawing process; when it is unstable, scrapings are collected to detect the penetration of steel components inside the copper layer; the electroplating current density is adjusted according to the detection results, thereby ensuring the wire drawing quality of the copper-clad steel wire and the purity of the copper layer, and avoiding the performance degradation caused by the penetration of steel components. At the same time, the electroplating current density is adjusted according to the scraping detection results, the electroplating process is optimized, and the conductive performance and structural stability of the wire are improved.

[0039] Furthermore, the present invention determines the penetration of steel components in the copper layer by detecting the iron content of scraps through the second layer, evaluates the electroplating process based on the uniformity of the coating distribution, adjusts the electroplating temperature or stirring speed when it is unqualified, accurately judges the penetration of steel components inside the copper layer, avoids the degradation of wire performance caused by the penetration of steel components, evaluates the qualification of the electroplating process based on the uniformity of the coating distribution, ensures the quality and uniformity of the electroplating layer, and provides stable conductive performance for the wire. When the electroplating process is unqualified, the electroplating temperature or stirring speed is adjusted according to the deviation of the coating distribution uniformity, thereby improving the quality of the electroplating layer and the overall performance of the wire, ensuring the quality and performance of the wire, and improving the structural stability of the wire.

[0040] Furthermore, the present invention adjusts the drawing speed of the wire drawing machine according to the difference between the coating distribution uniformity and the preset value when the electroplating process is qualified but the wire drawing process is unqualified, thereby ensuring the stability and controllability of the wire drawing process, avoiding wire quality problems caused by improper wire drawing speed, and improving the production efficiency and stability of the wire.

[0041] Furthermore, the present invention uses a wire bundling machine to twist copper-clad aluminum wires and coat them on the outside of stable copper-clad steel wires to form a circular conductor structure. The twisting and coating process is evaluated based on the composite morphology index. When it is unqualified, the production speed or stretching tension is adjusted to ensure the stability and quality of the circular conductor structure. The composite morphology index is used as an evaluation indicator to comprehensively reflect the morphological characteristics of the conductor structure, thereby accurately judging the eligibility of the twisting and coating process, optimizing the compactness and uniformity of the conductor structure, and improving the stability of current transmission. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 This is a flow chart of a method for preparing ultra-fine alloy wire for automobiles according to an embodiment of the present invention;

[0043] Figure 2 This is a flow chart for determining whether a copper-clad steel wire drawing process is stable according to an embodiment of the present invention;

[0044] Figure 3 A flow chart showing whether an electroplating process is qualified according to an embodiment of the present invention;

[0045] Figure 4 This is a structural diagram of an ultra-fine alloy wire for automobiles according to an embodiment of the present invention;

[0046] In the figure, 1. Copper-clad steel wire; 2. Copper-clad aluminum wire; 3. Insulation layer. DETAILED DESCRIPTION

[0047] In order to make the objects and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are merely used to explain the present invention and are not intended to limit the present invention.

[0048] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0049] It should be pointed out that the data in this embodiment are obtained by comprehensive analysis and evaluation of the historical test data and the corresponding historical test results of the three months before this test. It can be understood by those skilled in the art that the present invention can determine the above parameters for a single item by selecting the value with the highest proportion as the preset standard parameter based on the data distribution, using weighted summation to use the obtained value as the preset standard parameter, substituting each historical data into a specific formula and using the value obtained by the formula as the preset standard parameter or other selection methods, as long as the present invention can clearly define the different specific situations in the single determination process through the obtained values.

[0050] See also Figure 1 As shown, it is a flow chart of a method for preparing ultra-fine alloy wire for automobiles according to an embodiment of the present invention.

[0051] An embodiment of the present invention provides a method for preparing ultra-fine alloy wire for automobiles, comprising:

[0052] Step S1, obtaining a plurality of aluminum wires and steel core wires;

[0053] Step S2, electroplating a copper layer on the steel core wire to obtain a copper-clad steel wire, drawing the copper-clad steel wire through a wire drawing machine, and determining whether the copper-clad steel wire drawing process is stable based on the wire diameter fluctuation of the copper-clad steel wire;

[0054] Step S3, collecting scrapings from the surface of the copper-clad steel wire when the wire drawing process is unstable, and determining whether there is steel component penetration in the copper layer based on the copper content or iron content of the scrapings;

[0055] Step S4, under the condition that it is determined that steel component penetration exists, adjusting the current density based on the ratio of the copper content to the preset copper content or determining whether the electroplating process is qualified based on the uniformity of the coating distribution of the copper-clad steel wire after drawing;

[0056] Step S5, electroplating a copper layer on the aluminum wire to obtain a copper-clad aluminum wire, twisting multiple groups of the copper-clad aluminum wires by a wire bundling machine and wrapping them around the copper-clad steel wire that is stable during the wire drawing process to form a circular conductor structure;

[0057] Step S6, determining whether the twisting and coating process is qualified based on the composite morphology index of the circular conductor structure, and adjusting the production speed or stretching tension according to the relative difference between the composite morphology index and a preset composite morphology index;

[0058] Step S7: using an extruder to cover the outside of the circular conductor structure with polyvinyl chloride, cross-linked polyethylene and fluoroplastic to obtain an insulating layer.

[0059] During implementation, the thickness of the electroplated copper layer is 0.2 mm, the copper content of the copper layer is 99.95%, the volume proportion of copper in the copper-clad steel wire is 40%-60%, preferably 50%, and the volume proportion of copper in the copper-clad aluminum wire is 20%-40%, preferably 30%. The volume proportion value range and preferred value of the copper can be determined according to actual conditions, and are not specifically limited here and will not be repeated.

[0060] Specifically, the present invention can timely discover and solve the problem of wire diameter fluctuation caused by unstable wire drawing by monitoring the stability of the copper-clad steel wire drawing process, thereby ensuring the quality of the copper-clad steel wire. By collecting scrapings from the surface of the copper-clad steel wire when the wire drawing process is unstable and analyzing whether there is steel component penetration inside the copper layer, the purity and performance of the material are guaranteed, providing a more reliable conductive basis for the wire. After the copper layer is electroplated on the aluminum wire to obtain the copper-clad aluminum wire, it is twisted and wrapped around the outside of the copper-clad steel wire with stable wire drawing to form a circular conductor structure. By monitoring the composite morphology index of the circular conductor structure, the qualification of the twisting and wrapping process is accurately evaluated, and the production speed or stretching tension is adjusted according to the evaluation results to optimize the compactness and uniformity of the conductor structure, thereby improving the mechanical strength of the wire and ensuring the stability of current transmission, thereby improving the structural stability of the ultra-fine alloy wire for automobiles.

[0061] Specifically, a copper layer is electroplated on the steel core wire to obtain a copper-clad steel wire, and the copper-clad steel wire is drawn by a wire drawing machine.

[0062] During implementation, the current density range during the electroplating process is 10A / dm²-15A / dm², preferably 12A / dm², the plating solution temperature range is 45°C-55°C, preferably 50°C, the stirring speed range of the plating tank is 280rpm-320rpm, preferably 300rpm, the current density value is obtained by taking the average value of the current density when several qualified cables were prepared in the past, and the plating solution temperature is obtained by taking the average value of the plating solution temperature when several qualified cables were prepared in the past. The value range and preferred value of the stirring speed can be determined according to actual conditions, and are not specifically limited here and will not be repeated.

[0063] During the implementation process, the drawing speed range of the wire drawing machine is 5m / min-15m / min, and the preferred value is 10m / min. The tensile tension range is 80N-100N, and the preferred value is 90N. In the implementation, the value range and preferred value of the drawing speed and tensile tension can be determined according to actual conditions. The wire drawing machine is a straight-type wire drawing machine or an inverted wire drawing machine, which is not specifically limited here and will not be repeated.

[0064] See also Figure 2 As shown, it is a flow chart of determining whether the copper-clad steel wire drawing process is stable according to an embodiment of the present invention.

[0065] Specifically, in an embodiment of the present invention, under the condition of determining the copper-clad steel wire drawing, whether the copper-clad steel wire drawing process is stable is determined according to a comparison result of the wire diameter fluctuation of the copper-clad steel wire during the drawing process and the preset wire diameter fluctuation;

[0066] When the wire diameter fluctuation is less than or equal to the preset wire diameter fluctuation, it is determined that the copper-clad steel wire drawing process is stable;

[0067] When the wire diameter fluctuation is greater than the preset wire diameter fluctuation, it is determined that the copper clad steel wire drawing process is unstable.

[0068] In an embodiment of the present invention, the preset wire diameter fluctuation value is 0.01 mm. The preset wire diameter fluctuation is obtained when the stable wire diameter fluctuation in several historical copper-clad steel wire drawing processes takes the maximum value. However, the above value is not limited to this. Those skilled in the art can also adjust the value according to actual needs.

[0069] During the implementation process, a laser diameter gauge is used to select several inspection points on the copper-clad steel wire. The wire diameter fluctuation is the ratio of the sum of the absolute values ​​of the upper and lower offset distances of the wire diameters of all inspection points relative to the horizontal plane to the number of inspection points.

[0070] Specifically, under the condition that the copper clad steel wire drawing process is determined to be unstable, the embodiment of the present invention selects several sampling points on the surface of the copper clad steel after drawing with a preset spacing of 2 cm, and the area value range of the sampling points is 0.5 mm 2 -2mm 2 , preferably 1mm 2 The first detection method is to scrape off the surface copper layer at the sampling point to a depth of 50% of the copper layer thickness, collect the scrapings at each sampling point and detect whether they contain steel; the second detection method is to scrape off the copper layer at the sampling point until the steel core wire is just exposed, collect the scrapings at each sampling point and detect whether they contain steel, that is, detect the iron content. The detection means is EDX detection or chemical titration method, which is not specifically limited here and will not be repeated.

[0071] Specifically, under the condition of determining the first layer detection method, the embodiment of the present invention determines whether there is steel component penetration in the copper layer according to the comparison result of the copper content of the scrapings and the preset copper content;

[0072] When the copper content is less than the preset copper content, it is determined that steel components have penetrated into the copper layer;

[0073] When the copper content is greater than or equal to the preset copper content, it is determined that steel components penetrate into the copper layer.

[0074] In the embodiment of the present invention, the preset copper content is 99.95%, which is the copper content of the copper layer. However, the above value is not limited thereto, and those skilled in the art may also adjust the value according to actual needs.

[0075] Specifically, the embodiment of the present invention determines the adjustment current density based on the comparison result of the ratio of the copper content to the preset copper content and the preset ratio under the condition that the steel component penetration is determined in the copper layer in the first layer detection mode;

[0076] When the ratio is less than or equal to the preset ratio, it is determined to increase the electroplating current density to a corresponding value using a first preset current density adjustment coefficient of 1.05;

[0077] When the ratio is greater than the preset ratio, it is determined to increase the electroplating current density to a corresponding value using a second preset current density adjustment coefficient of 1.09;

[0078] The ratio is the ratio of the copper content to the preset copper content,

[0079] In the embodiment of the present invention, the preset ratio is 0.95, but the above value is not limited thereto, and those skilled in the art may also adjust the value according to actual needs.

[0080] In an embodiment of the present invention, the increased current density is the product of the preset current density adjustment coefficient and the current density. The preset current density adjustment coefficient includes a first preset current density adjustment coefficient, which has a value of 1.05 and a second preset current density adjustment coefficient, which has a value of 1.09. In order to ensure that the adjusted current density meets actual needs, the adjustment range should not be too large, so the corresponding adjustment coefficient is set to control the adjustment range.

[0081] Specifically, the present invention determines the wire drawing stability by monitoring the wire diameter fluctuation during the copper-clad steel wire drawing process; when it is unstable, scrapings are collected to detect the penetration of steel components inside the copper layer; the electroplating current density is adjusted according to the detection results, thereby ensuring the wire drawing quality of the copper-clad steel wire and the purity of the copper layer, and avoiding the performance degradation caused by the penetration of steel components. At the same time, the electroplating current density is adjusted according to the scraping detection results, the electroplating process is optimized, and the conductive performance and structural stability of the wire are improved.

[0082] Specifically, under the condition of determining the second layer detection, the embodiment of the present invention determines whether there is steel component penetration in the copper layer according to the comparison result of the iron content of the scrapings and the preset iron content;

[0083] When the iron content is less than or equal to the preset iron content, it is determined that no steel component penetrates into the copper layer;

[0084] When the iron content is greater than or equal to the preset iron content, it is determined that steel components penetrate into the copper layer.

[0085] In the embodiment of the present invention, the preset iron content is 0.05%. The iron content is obtained by taking the average of the iron contents of several historical determinations of the presence of steel component penetration in the copper layer. However, the above value is not limited to this, and those skilled in the art can also adjust the value according to actual needs.

[0086] See also Figure 3 As shown, it is a flow chart of determining whether the electroplating process is qualified according to an embodiment of the present invention.

[0087] Specifically, in the embodiment of the present invention, under the condition that the second layer detection determines that there is steel component penetration inside the copper layer, whether the electroplating process is qualified is determined based on the comparison result of the coating distribution uniformity of the copper-clad steel wire after drawing and the preset coating distribution uniformity;

[0088] When the coating distribution uniformity is less than or equal to the preset coating distribution uniformity, the electroplating process is determined to be unqualified;

[0089] When the coating distribution uniformity is greater than the preset coating distribution uniformity, it is determined that the electroplating process is qualified but the wire drawing process is unqualified.

[0090] In an embodiment of the present invention, the preset coating distribution uniformity value is 0.93. The preset coating distribution uniformity is obtained by taking the average value of the qualified coating distribution uniformity of several historical electroplating processes, but the above value is not limited to this. Those skilled in the art can also adjust the value according to actual needs.

[0091] During implementation, the coating distribution uniformity is the standard deviation of the scraping thickness and the copper layer thickness at several sampling points.

[0092] Specifically, in an embodiment of the present invention, when it is determined that the electroplating process is unqualified, the electroplating temperature or stirring speed is adjusted according to a comparison result of the absolute difference between the coating distribution uniformity and the preset coating distribution uniformity and the preset absolute difference;

[0093] When the absolute difference is less than or equal to the preset absolute difference, it is determined to increase the stirring speed to a corresponding value using a preset stirring speed adjustment coefficient of 1.15;

[0094] When the absolute difference is greater than the preset absolute difference, it is determined to increase the electroplating temperature to a corresponding value using a preset electroplating temperature adjustment coefficient of 1.12;

[0095] The absolute difference is the absolute difference between the coating distribution uniformity and the preset coating distribution uniformity.

[0096] In the embodiment of the present invention, the preset absolute difference value is 0.25, but the above value is not limited thereto, and those skilled in the art may also adjust the value according to actual needs.

[0097] In an embodiment of the present invention, the increased stirring speed is the product of the stirring speed and the preset stirring speed adjustment coefficient, and the preset stirring speed adjustment coefficient is 1.15; the increased electroplating temperature is the product of the electroplating temperature and the preset electroplating temperature adjustment coefficient, and the preset electroplating temperature adjustment coefficient is 1.12. In order to ensure that the adjusted stirring speed and electroplating temperature meet actual needs, the adjustment range should not be too large, so the adjustment coefficient is set accordingly to control the adjustment range.

[0098] Specifically, the present invention determines the penetration of steel components in the copper layer by detecting the iron content of scraps through the second layer, evaluates the electroplating process according to the uniformity of the coating distribution, adjusts the electroplating temperature or stirring speed when it is unqualified, accurately judges the penetration of steel components inside the copper layer, avoids the degradation of wire performance caused by the penetration of steel components, evaluates the qualification of the electroplating process according to the uniformity of the coating distribution, ensures the quality and uniformity of the electroplating layer, and provides stable conductive performance for the wire. When the electroplating process is unqualified, the electroplating temperature or stirring speed is adjusted according to the deviation of the coating distribution uniformity, thereby improving the quality of the electroplating layer and the overall performance of the wire, ensuring the quality and performance of the wire, and improving the structural stability of the wire.

[0099] Specifically, in an embodiment of the present invention, under the condition that it is determined that the electroplating process is qualified but the wire drawing process is unqualified, the wire drawing machine parameters are adjusted according to the comparison result of the difference between the coating distribution uniformity and the preset coating distribution uniformity and the preset difference;

[0100] When the difference is less than or equal to the preset difference, it is determined to reduce the drawing speed of the wire drawing machine to a corresponding value using a first preset drawing speed adjustment coefficient of 0.96;

[0101] When the difference is greater than the preset difference, it is determined to reduce the drawing speed of the wire drawing machine to a corresponding value using a second preset drawing speed adjustment coefficient of 0.93;

[0102] The difference is the difference between the coating distribution uniformity and the preset coating distribution uniformity.

[0103] In the embodiment of the present invention, the preset difference value is 0.05, but the above value is not limited thereto, and those skilled in the art may also adjust the value according to actual needs.

[0104] In an embodiment of the present invention, the reduced drawing speed is the product of preset drawing speed adjustment coefficients, and the preset drawing speed adjustment coefficients include a first preset drawing speed adjustment coefficient, which has a value of 0.96 and a second preset drawing speed adjustment coefficient, which has a value of 0.93. In order to ensure that the adjusted drawing speed meets actual needs, the adjustment range should not be too large, so the adjustment coefficient is set accordingly to control the adjustment range.

[0105] Specifically, the present invention adjusts the drawing speed of the wire drawing machine according to the difference between the coating distribution uniformity and the preset value when the electroplating process is qualified but the wire drawing process is unqualified, thereby ensuring the stability and controllability of the wire drawing process, avoiding wire quality problems caused by improper wire drawing speed, and improving the production efficiency and stability of the wire.

[0106] Specifically, a copper layer is electroplated on the aluminum wire to obtain a copper-clad aluminum wire, and a plurality of groups of the copper-clad aluminum wires are twisted by a wire bundling machine and wrapped around the copper-clad steel wire with a stable wire drawing process to form a circular conductor structure.

[0107] In an embodiment of the present invention, the main engine speed range of the wire bundling machine is 100rpm-150rpm, preferably 120rpm, and the production speed range is 100m / min-120m / min, preferably 110m / min. In implementation, the value range and preferred value of the main engine speed and production speed can be determined according to actual conditions. The type of the wire bundling machine is a single-filament wire bundling machine or a multi-filament wire bundling machine, which is not specifically limited here and will not be repeated.

[0108] Specifically, in an embodiment of the present invention, under the condition of determining that a circular conductor structure is formed, whether the twisting and coating process is qualified is determined according to a comparison result of the composite morphology index of the circular conductor structure and a composite morphology index threshold;

[0109] When the composite topography index is less than or equal to the composite topography index threshold, it is determined that the twisting and covering process is unqualified;

[0110] When the composite morphology index is greater than the composite morphology index threshold, it is determined that the twisting and covering process is qualified.

[0111] In the embodiment of the present invention, the composite topography index threshold is set to 0.85, but the above value is not limited thereto, and those skilled in the art may also adjust the value according to actual needs.

[0112] During implementation, the composite morphology index is the product of the cross-sectional ellipticity of the circular conductor structure and the ratio of the twisted gap area, and the cross-sectional area ellipticity and the twisted gap area are both obtained by a laser caliper.

[0113] Specifically, in an embodiment of the present invention, under the condition that the stranding coating process is determined to be unqualified, the production speed or the stretching tension is adjusted according to the comparison result of the relative difference between the composite topography index threshold and the composite topography index and the preset relative difference;

[0114] When the relative difference is less than or equal to the preset relative difference, it is determined to increase the production speed of the bundler to a corresponding value using a preset production speed adjustment coefficient of 1.06;

[0115] When the relative difference is greater than the preset relative difference, it is determined that the tensile tension of the wire drawing machine is reduced to the corresponding value by using the preset tensile tension adjustment coefficient of 0.94.

[0116] The relative difference is the relative difference between the composite topography index threshold and the composite topography index.

[0117] In the embodiment of the present invention, the preset relative difference value is 0.1, but the above value is not limited thereto, and those skilled in the art may also adjust the value according to actual needs.

[0118] In an embodiment of the present invention, the increased production speed is the product of the production speed and the preset production speed adjustment coefficient, and the preset production speed adjustment coefficient is 1.06; the reduced stretching tension is the product of the stretching tension and the preset stretching tension adjustment coefficient, and the preset stretching tension adjustment coefficient is 0.94. In order to ensure that the adjusted production speed and stretching tension meet actual needs, the adjustment range should not be too large, so the adjustment coefficient is set accordingly to control the adjustment range.

[0119] Specifically, the present invention uses a wire bundling machine to twist copper-clad aluminum wires and coat them on the outside of stable copper-clad steel wires to form a circular conductor structure. The twisting and coating process is evaluated based on the composite morphology index. If it is unqualified, the production speed or stretching tension is adjusted to ensure the stability and quality of the circular conductor structure. The composite morphology index is used as an evaluation indicator to comprehensively reflect the morphological characteristics of the conductor structure, thereby accurately judging the eligibility of the twisting and coating process, optimizing the compactness and uniformity of the conductor structure, and improving the stability of current transmission.

[0120] See also Figure 4, which is a structural diagram of an ultra-fine alloy wire for automobiles according to an embodiment of the present invention.

[0121] The embodiment of the present invention further provides an ultra-fine alloy wire for automobiles, comprising:

[0122] Copper-clad steel wire, which is used as a conductor to transmit electrical energy;

[0123] Copper-clad aluminum wire, which is coated on the outside of the copper-clad steel wire to protect the copper-clad steel wire;

[0124] The insulating layer is coated on the outside of the copper-clad aluminum wire to provide electrical isolation for the alloy wire.

[0125] Thus far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art may make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will fall within the scope of protection of the present invention.

[0126] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A method for preparing ultra-fine alloy wire for automobiles, characterized in that: include: Obtain some aluminum wire and steel core wire; electroplating a copper layer on the steel core wire to obtain a copper-clad steel wire, drawing the copper-clad steel wire through a wire drawing machine, and determining whether the copper-clad steel wire drawing process is stable based on the wire diameter fluctuation of the copper-clad steel wire; Collecting scrapings from the surface of the copper-clad steel wire when the wire drawing process is unstable, and determining whether there is steel component penetration inside the copper layer based on the copper content or iron content of the scrapings; Under the condition that the presence of steel component penetration is determined, the current density is adjusted based on the ratio of the copper content to the preset copper content, or the plating distribution uniformity of the copper-clad steel wire after drawing is determined to be qualified; Electroplating a copper layer on the aluminum wire to obtain a copper-clad aluminum wire, twisting a plurality of groups of the copper-clad aluminum wires by a wire bundling machine and wrapping them around the copper-clad steel wire that is stable during the wire drawing process to form a circular conductor structure; determining whether the twisting and coating process is qualified based on the composite shape index of the circular conductor structure, so as to adjust the production speed or the stretching tension according to the relative difference between the composite shape index and the preset composite shape index; The composite topography index is the product of the cross-sectional ellipticity of the circular conductor structure and the strand gap area ratio, wherein the cross-sectional area ellipticity and the strand gap area are both obtained by a laser caliper. Polyvinyl chloride, cross-linked polyethylene and fluoroplastic are coated on the outside of the circular conductor structure through an extruder to obtain an insulation layer.

2. The method for preparing ultra-fine alloy wire for automobiles according to claim 1, wherein: Based on the comparison result that the wire diameter fluctuation of the copper-clad steel wire during the wire drawing process is greater than the preset wire diameter fluctuation, it is determined that the copper-clad steel wire drawing process is unstable, and based on the comparison result that the copper content of the scrapings under the first layer detection method is less than the preset copper content, it is determined that steel components have penetrated into the copper layer; Among them, the first layer detection method is to scrape the surface copper layer from several sampling points to a depth of 50% of the copper layer thickness, collect the scrapings from each sampling point and detect whether they contain steel.

3. The method for preparing ultra-fine alloy wire for automobiles according to claim 2, characterized in that: Under the condition that steel components are infiltrated into the copper layer, the process of adjusting the current density includes: dividing the copper content by a preset copper content; Set a number of adjustment coefficients corresponding to the corresponding ratios; increasing the current density of electroplating based on a number of the adjustment factors; The corresponding relationship between the corresponding ratio and the increase in the current density of the electroplating is set to adjust the current density.

4. The method for preparing ultra-fine alloy wire for automobiles according to claim 1, wherein: Based on the comparison result that the wire diameter fluctuation of the copper-clad steel wire during the wire drawing process is greater than the preset wire diameter fluctuation, it is determined that the copper-clad steel wire drawing process is unstable, and based on the comparison result that the iron content of the scrapings under the second layer detection method is greater than or equal to the preset iron content, it is determined that steel components have penetrated into the copper layer; The second-layer detection method is to scrape the copper layer from several sampling points until the steel core wire is just exposed, collect the scrapings from each sampling point and detect whether they contain steel.

5. The method for preparing ultra-fine alloy wire for automobiles according to claim 4, characterized in that: The electroplating process is determined to be unqualified based on the comparison result that the coating distribution uniformity of the copper-clad steel wire after drawing is less than or equal to the preset coating distribution uniformity.

6. The method for preparing ultra-fine alloy wire for automobiles according to claim 5, characterized in that: Under the condition that the electroplating process is determined to be unqualified, the process of adjusting the electroplating temperature or stirring speed of the electroplating process includes: Taking the absolute value of the difference between the coating distribution uniformity and the preset coating distribution uniformity; Determining to increase the stirring speed by a preset stirring speed adjustment coefficient based on the comparison result that the absolute difference is less than or equal to the preset absolute difference; Based on the comparison result that the absolute difference is greater than the preset absolute difference, it is determined to increase the electroplating temperature by a preset electroplating temperature adjustment coefficient.

7. The method for preparing ultra-fine alloy wire for automobiles according to claim 4, characterized in that: Based on the comparison result that the coating distribution uniformity of the copper-clad steel wire after wire drawing is greater than the preset coating distribution uniformity, it is determined that the electroplating process is qualified but the wire drawing process is unqualified.

8. The method for preparing ultra-fine alloy wire for automobiles according to claim 7, characterized in that: Under the condition that the electroplating process is qualified but the wire drawing process is unqualified, the process of adjusting the wire drawing machine parameters includes: Subtracting the coating distribution uniformity from the preset coating distribution uniformity; Determining, based on the comparison result that the difference is less than or equal to the preset difference, to reduce the drawing speed of the wire drawing machine by a first preset drawing speed adjustment coefficient; Based on the comparison result that the difference is greater than the preset difference, it is determined that the drawing speed of the wire drawing machine is reduced by a second preset drawing speed adjustment coefficient.

9. The method for preparing ultra-fine alloy wire for automobiles according to claim 1, wherein: Based on the comparison result that the composite morphology index of the circular conductor structure is less than or equal to the composite morphology index threshold, it is determined that the twisted coating process is unqualified, and based on the comparison result of the relative difference between the composite morphology index threshold and the composite morphology index and the preset relative difference, it is determined to increase the production speed of the wire bundling machine by the preset production speed adjustment coefficient or to reduce the tensile tension of the wire drawing machine by the preset tensile tension adjustment coefficient.

10. An ultra-fine alloy wire for automobiles, produced by the method for producing an ultra-fine alloy wire for automobiles according to any one of claims 1 to 9, characterized in that: include: Copper-clad steel wire, which is used as a conductor to transmit electrical energy; Copper-clad aluminum wire, which is coated on the outside of the copper-clad steel wire to protect the copper-clad steel wire; The insulating layer is coated on the outside of the copper-clad aluminum wire to provide electrical isolation for the alloy wire.

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