JPH0726110B2 - Conductive wire manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a method for manufacturing a conductive wire in which at least a surface layer is made of Al or Cu, and a lead wire for electronic parts is drawn by plastic working. Regarding

[Prior Art] A wire such as a power transmission line, a lead wire for electronic parts, or a composite conductive wire in which a metal core wire is coated with a non-ferrous metal such as copper or aluminum (hereinafter referred to as a composite wire) is hot or A wire material is manufactured by a known method such as warm extrusion or hot rolling, and the diameter of the wire material is reduced by a wire drawing machine having a drawing die to manufacture a conductive wire having a predetermined size. Industrially, a continuous wire drawing machine in which a plurality of wire drawing machines each having a drawing die are arranged on a line is used to manufacture a conductive wire having a predetermined size.

In the production of the composite wire, since the deformation resistance of the core wire and the covering material is different, the cross-sectional area ratio between the core wire and the covering layer also changes as the wire is drawn. Therefore, the change in the cross-sectional area ratio between the core wire and the coating layer is predicted in advance, and the wall thickness of the coating layer of the wire material is determined accordingly and the wire drawing is performed.

Conventionally, in such wire drawing, a liquid lubricant and a powder lubricant have been generally used as a lubricant for processing.

As the liquid lubricant, a synthetic oil such as mineral oil or ester oil or a mixed oil thereof is used as a base oil, and various additives such as "petroleum product additives" (edited by Toshio Sakurai, Shoshobo, May 1973). There is a mixture of an oiliness improver such as higher fatty acids and higher alcohols, and extreme pressure agents of phosphorus, chlorine and sulfur which are described in "Monthly issue".

On the other hand, as the powder lubricant, metal soap powder such as calcium soap or sodium soap is used, and the powder is press-fitted between the wire material and the die to perform wire drawing.

For wire drawing of steel only, a lubricating oil containing metal soap powder having a particle size of 100 μm or less mixed with polybutene (Japanese Patent Laid-Open No. 55-
135198 gazette). In addition, a lubricant for metal drawing, which contains paraffin wax, chlorinated paraffin and phosphite ester, or phosphoric acid ester (JP-A-62-15
3396), and a lubricant in which oil or fat or wax, a polymer dispersant, a surfactant and the like are dispersed in water (JP-A-55-147593).

[Problems to be Solved by the Invention] In wire drawing of a wire material by a continuous wire drawing machine, since the wire diameter is reduced each time it passes through a drawing die, it is necessary to increase the wire drawing speed toward the subsequent stage. is there. The wire drawing speed in the final step may reach 250 to 400 m / min.

In the case of a composite wire, the surface properties of the coating layer, the uniformity of conductivity, and the like are strict, and in particular, in order to keep the conductivity constant, a uniform thickness of the coating layer is required over the entire length of the conductive wire.
At the same time, the surface of the wire is seized due to the plastic working, and "galling" occurs.
Also, it must have a good surface quality without "discoloration" due to deterioration of the lubricating oil.

The surface texture of the wire drawing is affected by the cross-sectional area ratio between the core wire and the coating layer, the shape of the drawing die, the drawing ratio, and the like, but the effect of the lubricant is particularly large. In addition, high-speed wire drawing is required to improve productivity, but in order to speed up wire drawing, it is necessary to significantly improve the performance of the lubricating oil.

Conventionally, various lubricants have been used in order to improve such points, but no lubricant has been able to achieve both high speed wire drawing and good surface properties.

In general, high-viscosity lubricating oil is unlikely to come into contact with other metals and is effective in preventing seizure during wire drawing. However, since the viscosity resistance of the lubricating oil is large, the temperature rises due to the wire drawing work, and as a result, the viscosity of the lubricating oil decreases and seizure occurs. In addition, since the mechanical strength of the wire material itself decreases due to the temperature rise during wire drawing, conventional wire drawing
The limit is approximately 0 to 150 m / min.

In addition, the above-mentioned high-viscosity lubricating oil has poor handling and workability such as replenishment, and if it scatters around and adheres to the equipment surface, floor surface, etc., it has high viscosity and sticks to work clothes and shoes. However, this causes a problem in terms of work safety that the worker is caught in the wire drawing machine or falls.

On the other hand, a lubricant suitable for wire drawing of steel is not suitable for processing non-ferrous metal, especially copper or aluminum which is a soft material, and seizure and surface cracking are likely to occur. Surface cracking is a phenomenon that occurs when the frictional force between the material and the die is greater than the shear resistance of the non-ferrous metal material itself.

Further, since these lubricants contain a large amount of metal soap, there is a drawback that the surface of the processed product is discolored and the commercial value is lowered.

Viscosity of 171,00 as a lubricating oil for plastic working of aluminum
Polybutene of 0cSt (40 ℃) or higher can be used. However, as mentioned above, the higher the viscosity of a lubricating oil, the less the seizure between the material and the die occurs, and wire drawing is possible even at a wire drawing speed of about 200 m / min. There is a problem in workability and safety as described above.

As described above, there have been many problems in the conventional wire drawing with a lubricant.

A first object of the present invention is to provide a conductive wire, which is made of a non-ferrous metal typified by Al or Cu, or a wire material obtained by coating a core wire of these with a wire drawing machine having a drawing die at a high speed. A manufacturing method is provided.

A second object of the present invention is to provide a method for manufacturing a conductive wire that has no problems in workability and safety.

[Means for Solving the Problems] The gist of the present invention for achieving the above object is as follows.

(1) At least one base oil selected from polybutene, polymethacrylate, polyisobutylene, ethylene-α-olefin copolymer and polyalkylene glycol on the surface of a wire material having at least a surface layer made of Al or Cu 98 ~ 75% by weight and a lubricating oil comprising 2 to 25% by weight of an additive selected from animal and vegetable fats or oils or aliphatic dicarboxylic acids having 5 to 36 carbon atoms, and passing through a drawing die for wire drawing, A method for producing a conductive wire, which comprises plastically working while forming a lubricating film on the surface of the wire material by heat generated by reducing the diameter of the wire material.

(2) At least one base oil selected from polybutene, polymethacrylate, polyisobutylene, ethylene-α-olefin copolymer, and polyalkylene glycol on the surface of the wire material whose surface layer is made of Al or Cu 98 ~ 75% by weight and a lubricating oil comprising 2 to 25% by weight of an additive selected from animal and vegetable fats or oils or aliphatic dicarboxylic acids having 5 to 36 carbon atoms, and passing through a drawing die for wire drawing, A method for producing a conductive wire, comprising twisting two or more plastic-worked wires while forming a lubricating film on the surface of the wire material by heat generated by reducing the diameter of the wire material.

(3) Viscosity of the base oil is 300-50,000cSt (40 ℃)
The method for producing a conductive wire as described above, which is

Next, a method for producing the conductive wire of the present invention will be described with reference to the drawings.

As shown in Fig. 2, Al or Cu wound around the supply 1
The wire material 2 made of (or an alloy of these) is guided to the first pulley 8 and passes through the guide 3 of the wire drawing machine No. 1 to apply the lubricating oil 4 to the surface of the wire material, and the drawing die 5 and the storage die. The diameter of the wire is reduced to the wire diameter of the first stage by the wire drum 7.
To be wound up.

Next, it is guided to the wire drawing machine No. 2 by the next pulleys 8 ', 8 and reduced in diameter to the second stage wire diameter in the same manner as above. This is sequentially drawn to a wire diameter of a predetermined size (No. n stages).

Next, after being introduced into the processing chamber 9 and straightening the strain through the straightening machine 10, the solvent 11 and the rotary brush 12 remove the lubricating oil adhering to the surface, and the air blow 13 dries. The dried conductive wire is wound on the winding drum 15 attached to the winding machine 14.

Next, the lubricating oil for wire drawing used in the present invention will be described.

Lubricating oils include base oils and additives. Mineral oil is considered as a general base oil. However, mineral oil has a viscosity index of 100 or less, and the rate of decrease in viscosity with a rise in temperature is large. Therefore, the adhesion to the wire material surface is low,
Lubrication becomes poor and seizure or wire breakage of wire drawing material easily occurs, and smooth wire drawing cannot be performed. Furthermore, when the drawing die temperature is 120 ° C or higher, the surface of the wire drawing is discolored with such a base oil of mineral oil, which is not suitable for high speed wire drawing.

The present inventors have used as a base oil a liquid polymer compound selected from polybutene, polymethacrylate, polyisobutylene, and ethylene-α-olefin copolymer, and have excellent lubrication performance of animal and vegetable fats and oils or aliphatic dicarboxylic acids as additives. Therefore, the present invention has been completed, and it was found that the viscosity decrease with temperature rise is small, the adhesiveness to the surface of the wire material and the heat resistance are excellent. The liquid polymer compound is a liquid polymer that can be synthesized by a known method,
The viscosity can be freely adjusted by changing the molecular weight or selectively blending those having different molecular weights. 40 in terms of wire drawing conditions, workability, handleability, etc.
A viscosity in the range of 300 to 50,000 cSt is suitable.

Examples of additives (lubricity improvers) to be added to the base oil include castor oil, lard, linseed oil, soybean oil, beef tallow oil, lanolin and other animal and vegetable oils.

Further, similarly, the aliphatic dicarboxylic acid has 5 to 5 carbon atoms.
36 is good. Examples thereof include glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecane diacid, dodecane diacid, tridecane diacid, and dimer acid, and one or more of them are used.

The amount of the animal or vegetable fat or oil or the aliphatic dicarboxylic acid to be added to the liquid polymer compound of the base oil is 2 to 25% by weight, preferably 5 to 20% by weight. If the amount of the above-mentioned animal or vegetable oil or aliphatic dicarboxylic acid is less than 2% by weight, the effect of improving lubricity becomes insufficient and seizure easily occurs during wire drawing. Further, even if it exceeds 25% by weight, the anti-seizure effect is not further improved.

According to the present invention, the core wire material is a superconducting material, the coating layer is copper,
A composite wire made of aluminum non-ferrous metal can be similarly drawn at high speed.

[Operation] The lubricating oil used in the present invention has a small decrease in viscosity with respect to temperature, is thermally stable, and has excellent adhesion to the surface of the wire material. Form a film. In particular, the surface of the non-ferrous metal wire material, the film formed by the reaction of animal and vegetable fats and oils or aliphatic dicarboxylic acids that are additives of the lubricating oil, is formed on the plastic work surface, because it has excellent lubricating performance In addition, seizure of plastic processing of non-ferrous metal is prevented. It is presumed that the reaction film reacts with the surface of the non-ferrous metal material and the additive due to frictional heat with the die during plastic working to form a film of metal soap.

The metal soap film becomes a strong film and is formed at a local contact portion between the surface of the die and the surface of the wire material to prevent “burning” due to direct contact between the die and the material metal. Therefore, smooth plastic working can be performed. In particular, the effect is great in wire drawing, and seizure does not occur even in high speed wire drawing that has never been done.

[Examples] The present invention will be specifically described below with reference to Examples.

[Examples 1 to 11] Polyisobutylene having a viscosity of 650 cSt at 40 ° C. was used as a lubricating base oil, and 10% by weight of the fats and oils and the aliphatic dicarboxylic acids shown in Table 1 were added thereto and dissolved by heating to produce a lubricating oil. did. A steel wire was used as a core wire, and a composite wire material having a surface coated with copper was wire-drawn using the wire drawing machine shown in FIG. In addition,
FIG. 3 shows a schematic view of the die part.

A composite wire material 1 wound around a supply 1 is guided by a guide 3, and is dip-coated in a lubricating oil 4 while being reduced in diameter by a drawing die 5 equipped with a thermocouple 6, and a drum 7 mounted on a wire drawing machine.
Take up by.

Then, after straightening the strain through a straightening machine 10 installed in the processing chamber 9, a trichlene solvent 11 is sprayed on the rotary brush.
At 12, the lubricating oil adhering to the wire drawing surface was removed. After the solvent was removed by the air blow 13, this was taken up by the take-up drum 15 attached to the take-up machine 14.

The surface after wire drawing was visually observed to observe a seizure state and surface cracking. Further, the rising temperature of the drawing die [(temperature during processing)-(initial temperature)] was measured. The results are shown in Table 1. The wire drawing process was performed under the following conditions.

Wire material: Steel material coated with copper. (Cu-steel wire) Die shape: 2 degree reduction angle, conical die with a drawing diameter of 2.89 mm and bearing length of 2 mm Machining rate: 20.4% (diameter 3.24 mm to 2.89 mm diameter) Machining speed: 110 m / min Die temperature: 12 ℃ [Comparative Examples 1 to 7] Table 2 shows the lubricating oils used in each Comparative Example. The numerical value in parentheses indicates the viscosity (cSt) at 40 ° C.

[Example 12] A composite wire material in which aluminum was coated on the surface of a steel core wire using a lubricating oil having the same composition as in Examples 1 to 11 was subjected to wire drawing using the wire drawing machine shown in Fig. 1. Table 3 shows the results of the visual observation of the surface properties (burning and surface cracking) and the die rising temperature after wire drawing.

In addition, the roughness of the wire surface after drawing was measured with a circularity measuring machine (EC-4S manufactured by Kosaka Laboratory), and it was about ± 2 in the circumferential direction.
was μm.

Similarly, the surface roughness of Comparative Example 2 (using polybutene) and Comparative Example 5 (using polybutene + calcium soap) was about ± 4 μm.

[Examples 13 to 38] The lubricating oil prepared by heating and dissolving the base oil, fat and oil and aliphatic dicarboxylic acid shown in Table 4 was drawn at 15 to 17 ° C with the same wire drawing machine as in Example 2 to draw an aluminum-coated steel wire material. Wire processing was performed, and the die rising temperature and the properties of the wire drawing surface were examined. The results are shown in Table 4.

From the results shown in Table 4, the die temperature rises sharply when the blending amount of the oil or fat or the aliphatic dicarboxylic acid is less than 2% by weight. Also, the surface of the wire drawing is about to seize. If the blending amount exceeds 20% by weight, the property improvement tends to be saturated.

[Example 39] The same aluminum-coated steel wire material as in Example 2 was used as a lubricating oil in which polybutene having a viscosity of 200 to 300,000 cSt at 40 ° C was blended with 10% by weight of lanolin.
%, And the relationship between the viscosity of the base oil and the rising temperature of the die was measured. Results are shown in FIG.

If the viscosity is 300 cSt or less, the die temperature rises. Further, when the drawing was once stopped and the wire drawing process was performed again, the wire was sometimes broken.

On the other hand, when the temperature exceeds 35,000 cSt, the die temperature begins to rise, the amount of lubricating oil taken out increases, and it easily adheres to single-head wire drawing machines, winding drums, floor surfaces, etc. Handleability during replenishment is poor. From the viewpoint of workability and safety, the lubricating oil viscosity should be around 50,000 cSt.

Example 40 An aluminum-coated steel wire material with a diameter of 8.4 mm is shown in FIG. 2 using a lubricating oil consisting of 90% by weight of an ethylene-α-olefin copolymer having a viscosity of 31,000 cSt at 40 ° C. and 10% by weight of lanolin. Practical performance was evaluated by performing 11 stages (processes) of wire drawing with the continuous wire drawing machine shown. Table 5 shows the processing conditions, the surface properties after wire drawing, and the results of the cross-sectional ratio between the core wire and the coating layer.

As can be seen from the results in Table 5, the surface properties were extremely good, and smooth wire drawing could be performed. The cross-sectional ratio of the core wire and the coating layer is in the range of 34.8 to 36.0%,
It was extremely good. Further, the lubricating oil adhering to the wire drawing surface after 11 steps was washed with the trichlene solvent 11 and the rotating brush 12 in the processing chamber 9 shown in FIG. The oil could be removed almost completely.

Example 41 Aluminum-coated conductive wire obtained in Example 40 (strand diameter 2.9 mm
φ) was twisted using a tandem high-speed twisting machine under the conditions of 30 strands and a cross-sectional area of 200 mm ² , and the practical performance was evaluated. As a result, a normal twisted wire could be obtained without any scratches on the surface. Further, it is more effective to use the above-mentioned lubricating oil even during the twisted wire work.

Further, although the above-mentioned examples were all carried out for the case of the composite wire, the wire drawing work can be performed in the same manner even when the wire material is made of only Al or Cu.

[Effects of the Invention] According to the present invention, a wire material having at least a surface layer made of a non-ferrous metal such as Al or Cu can be drawn by plastic working without causing seizure, etc., and the surface properties of the processed product are also very excellent. It is possible to provide a high quality conductive wire.

Further, it has excellent seizure resistance and high lubricity even at high-speed wire drawing, so that high-speed wire drawing and high-speed stranded wire processing can be performed smoothly, and it is excellent in improving the quality and productivity of conductive wires. .

Furthermore, the conductivity of a composite conductive wire (constant coating thickness)
It is possible to provide a product that can sufficiently cope with.

Since the lubricating oil used in the wire drawing of the present invention has a low viscosity,
It is also excellent in workability and work safety.

[Brief description of drawings]

FIG. 1 is a schematic view of a wire drawing machine, FIG. 2 is a schematic view of a continuous wire drawing machine, FIG. 3 is a schematic view of a die part of the wire drawing machine, and FIG. 4 is a die rising temperature when drawing wire according to the present invention. It is a curve figure which shows the relationship of viscosity. 1 …… Supply, 2 …… Line material, 3 …… Guide, 4 ……
Lubricating oil, 5 ... Drawing die, 6 ... Thermocouple, 7 ... Wire drawing drum, 8 ... Pulley, 9 ... Processing chamber, 10 ... Straightener,
11 …… Solvent, 12 …… Rotating brush, 13 …… Air blow, 14
…… Winding machine, 15 …… Winding drum, 16 …… Load cell.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication C10M 107: 34 107: 02 107: 28 129: 34 129: 42 159: 08) C10N 20:02 30 : 06 40:24

Claims (3)

[Claims] 1. A surface of a wire material having at least a surface layer made of Al or Cu, and polybutene, polymethacrylate,
98 to 75% by weight of one or more base oils selected from polyisobutylene, ethylene-α-olefin copolymers, and polyalkylene glycols, and animal and vegetable oils or carbon atoms 5
~ 36 wt% of additives selected from aliphatic dicarboxylic acids of 2 to 25 wt% is applied and passed through a drawing die for wire drawing, and the heat generated by reducing the diameter of the wire material A method for producing a conductive wire, which comprises performing a plastic working while forming a lubricating film on the surface of the wire material. 2. A surface of a wire material having at least a surface layer made of Al or Cu, and polybutene, polymethacrylate,
98 to 75% by weight of one or more base oils selected from polyisobutylene, ethylene-α-olefin copolymers, and polyalkylene glycols, and animal and vegetable oils or carbon atoms 5
~ 36 wt% of additives selected from aliphatic dicarboxylic acids of 2 to 25 wt% is applied and passed through a drawing die for wire drawing, and the heat generated by reducing the diameter of the wire material A method for producing a conductive wire, characterized in that two or more plastic-processed wires are twisted together while forming a lubricating film on the surface of the wire material. 3. The viscosity of the base oil is 300 to 50,000 cSt (40
C.) The method for producing a conductive wire according to claim 1 or 2.