JP6288433B2 - Copper coil material, copper coil material manufacturing method, copper flat wire manufacturing method, and coated flat wire manufacturing method - Google Patents

Description

  The present invention relates to a coated rectangular wire used for a coil winding, a copper rectangular wire used for a coil winding conductor, a copper coil material used for a material such as a coil winding conductor, copper, etc. The present invention relates to a coil material manufacturing method and a copper rectangular wire manufacturing method. In particular, the present invention relates to a copper coil material suitable for a copper rectangular wire material having a relatively large cross-sectional area, and a copper coil material manufacturing method capable of manufacturing the copper coil material with high productivity.

  Conventionally, a coated wire called an enameled wire has been widely used for winding of a coil provided in a coil component such as a motor. This covered wire uses a metal wire made of copper (so-called pure copper) as a conductor, and an insulating coating made of a resin such as polyamideimide is provided on the surface of the conductor. Typical examples of the conductor include a round wire having a circular cross section and a rectangular flat wire. Since the winding using a rectangular wire as a conductor can form a coil with a high space factor, it is suitable as a constituent material of an automotive coil component that is desired to be small.

  The flat wire is typically produced by subjecting a wire drawing material to rolling (hereinafter sometimes referred to as flat processing). Specifically, a wire drawing material obtained by performing wire drawing and heat treatment on a copper roughing wire obtained by continuous casting and rolling is used as a raw material (bus wire), and this material is subjected to flattening to transform it into a desired shape such as a rectangular shape. By applying, the above-mentioned rectangular wire is obtained (for example, paragraph 0041 in the specification of Patent Document 1). By using a copper rough wire that can be mass-produced by continuous casting and rolling, the productivity of a wire drawing material that becomes a material of a copper flat wire, and hence the productivity of a copper flat wire can be increased.

JP2013-052434A

  Development of a copper wire suitable for a copper rectangular wire material having a relatively large cross-sectional area, which has high elongation and excellent productivity is desired.

In recent years, with the increase in output of automobile batteries and motors, there is an increasing demand for conductors for coil windings used in these coil components having a relatively large cross-sectional area (for example, about 10 mm ² ). . In order to produce a copper rectangular wire having a large cross-sectional area, a thicker material, that is, a copper material having a large cross-sectional area (for example, 12 mm ² or more) is required. However, in the conventional manufacturing method in which wire drawing and heat treatment are performed, it is difficult to manufacture a copper material having a large cross-sectional area excellent in elongation with high productivity. Due to the poor productivity of copper material, the productivity of copper cross-sections with large cross-sectional areas is also reduced.

Purpose is sized DoAra drawn wire (e.g., wire diameter (diameter) φ8mm~φ9.5mm about ≒ sectional area 50mm ² ~70mm ² about) Using, general-purpose on which can mass-produced DoAra wire rods themselves A wire drawing device or a continuous processing furnace can be used. Therefore, if the general-purpose copper roughing wire is used, it can contribute to mass production of a wire with a large cross-sectional area or a heat treatment material. However, when trying to obtain a wire with a large cross-sectional area from this copper rough wire, the cross-sectional area of this copper rough wire is small, so the degree of wire drawing work from this copper wire to a wire with a predetermined cross-sectional area Cannot be increased. Due to the low degree of wire drawing, it cannot be sufficiently softened even if heat treatment is applied to the wire drawing material after wire drawing. Therefore, when wire drawing is performed using the above-described general-purpose copper rough wire, mass production of a copper material having a large cross-sectional area that is completely softened and has sufficient elongation, that is, has high elongation, It is difficult to produce a copper material that is long and has a large cross-sectional area. If the elongation is insufficient, the processability is poor. When flattening is performed on a copper material that is inferior in workability, a copper flattened wire that is inferior in shape accuracy and dimensional accuracy may be formed, and the yield of the copper flattened wire is reduced. Here, a copper rectangular wire used for a coil winding conductor or the like has a narrow allowable range of shape accuracy and dimensional accuracy, and high accuracy is required. Therefore, it is desired that the copper material used for the copper rectangular wire has sufficient workability and typically has excellent elongation so that the occurrence of shape defects and dimensional defects can be reduced. In addition, in the wire drawing material (hard material) which has not performed heat processing after wire drawing, it is further inferior to workability and causes the fall of the yield of a copper flat wire further.

  Further, when the degree of wire drawing is low, there is a possibility that defects present in the copper rough drawing wire cannot be completely removed in the wire drawing process and remain in the wire drawing material. Defects present in the wire drawing material tend to remain in the copper rectangular wire. Here, when a flat wire is used as a conductor of a covered wire, if a surface defect such as a crack is present on the surface of the flat wire, a defect such as a bulge may occur due to the crack. Since the swollen part of the insulating coating becomes an electrical weak point, the covered wire in which the swollenness is present may not satisfy a desired withstand voltage characteristic and becomes a defective product. Accordingly, a copper material that is inferior in surface properties, in particular, a copper material that can produce a flat copper wire having a surface defect that causes a decrease in the yield of the covered wire is also defective.

  When a copper material with a large cross-sectional area is manufactured by performing wire drawing and heat treatment using a general-purpose copper rough drawing wire in this way, a long material can be manufactured, but the elongation is insufficient, and further the surface The yield may be reduced due to deterioration of properties. Therefore, it is desired to develop a copper material having high elongation and excellent productivity.

If copper rough wire with a larger cross-sectional area is used, a large degree of wire drawing work can be secured, and by performing wire drawing and heat treatment, a copper material having a large cross-sectional area that has high elongation and excellent surface properties can be obtained. It is done. However, this copper material cannot be said to have good productivity from the following points (1) to (4).
(1) A thick copper rough wire is easily wrinkled and requires a step of removing the curl and a step of improving straightness before wire drawing.
(2) Since a thick copper rough wire has high rigidity and it is difficult to continuously perform wire drawing, the number of rewinds in the wire drawing process is large. For example, it is necessary to perform feeding and winding for each pass.
(3) Although it is easy to obtain a thicker wire drawing material, if it is too thick, a continuous processing furnace cannot be used, and it may be softened only in a batch furnace.
(4) When a batch furnace is used, only a relatively short copper material can be produced, and a long copper material cannot be produced.

  Accordingly, one object of the present invention is to provide a copper coil material that is suitable for a copper rectangular wire material having a relatively large cross-sectional area, has high elongation, and is excellent in productivity. Another object of the present invention is to provide a method for producing a copper coil material, which is suitable for a material of a copper rectangular wire having a large cross section and can produce a copper coil material having high elongation with high productivity.

  Another object of the present invention is a copper rectangular wire suitable for a conductor of a coil winding, a coated rectangular wire including the copper rectangular wire, and a copper capable of producing a copper rectangular wire having a relatively large cross-sectional area with high productivity. The object is to provide a method of manufacturing a flat wire.

The copper coil material of the present invention is obtained by winding a copper wire made of pure copper or a copper alloy into a coil shape, the cross-sectional area of the copper wire is 12 mm ² or more and 40 mm ² or less, and the elongation at break of the copper wire is Is 30% or more, and the mass is 100 kg or more. The copper wire is provided with a lubricating layer on the surface thereof, and is used as a material for producing a copper rectangular wire by rolling.

  The method for producing a copper coil material of the present invention includes a step of preparing a continuous cast rolled material, a step of producing a copper wire by subjecting the continuous cast rolled material to conform extrusion, and a lubricating layer on the surface of the copper wire. And forming a copper coil material by winding it into a coil shape. The copper coil material is used as a material for producing a copper rectangular wire by rolling the copper wire material that has been rewound. It is done.

  The copper coil material of the present invention has high elongation and excellent productivity. The method for producing a copper coil material of the present invention can produce a copper coil material having high elongation with high productivity.

It is a schematic perspective view which shows the copper coil material of embodiment. It is a schematic block diagram which shows an example of a conform extrusion apparatus. It is process explanatory drawing explaining the process of the manufacturing method of the copper coil material of embodiment, and the manufacturing method of the copper flat wire of embodiment.

[Description of Embodiment of the Present Invention]
The present inventors have studied various manufacturing methods capable of mass-producing a copper material having a large cross-sectional area suitable for a copper rectangular wire material having a relatively large cross-sectional area. As a result, by subjecting the copper rough drawn wire obtained by continuous casting and rolling to conform extrusion, a long copper wire having high elongation and excellent surface properties can be obtained without performing wire drawing and heat treatment. And gained knowledge. Moreover, the knowledge that the copper flat wire excellent in a shape precision and a dimensional accuracy was obtained by performing a rolling process (flat square process) to this copper wire was acquired.

  Here, conform extrusion is widely used for extrusion of pure aluminum such as 1000 series aluminum in JIS standard (aluminum-coated steel wire, porous eccentric tube, etc.). Conform extrusion is used for copper coating such as copper-coated steel wire.

  Conform extrusion can form a profile extrusion material having various external shapes (for example, a rectangle, a polygon, an ellipse, etc.) as well as a circular line having a circular cross section. In addition, conform extrusion enables mass production of extruded materials having various cross-sectional areas (production of long extruded materials). Therefore, we tried to produce copper flat wire with large cross-sectional area directly by subjecting the copper rough wire to conform extrusion, resulting in shape defects and dimension defects that deviated from the specified shape accuracy and dimensional accuracy. It was. This is because copper is inferior in workability to pure aluminum. Therefore, when the copper rough wire was subjected to conform extrusion and the obtained extruded material was subjected to rolling processing (flat angle processing), a copper rectangular wire could be formed with high accuracy. In addition, when the obtained copper rectangular wire was coated with an insulating coating, it was difficult for the coating to swell. And the said extrusion material had high elongation and the surface property was also excellent. Therefore, it can be said that this extruded material can be suitably used for a copper rectangular wire material. The present invention is based on the above findings. First, the contents of the embodiment of the present invention will be listed and described.

(1) The copper coil material according to the embodiment is obtained by winding a copper wire made of pure copper or a copper alloy into a coil shape, and is used as a material for producing a copper rectangular wire by rolling. The cross-sectional area of the copper wire is 12 mm ² or more and 40 mm ² or less. The breaking elongation of the copper wire is 30% or more. The mass of the copper coil material is 100 kg or more. A lubricating layer is provided on the surface of the copper wire.

The copper coil material of the embodiment is suitably used for a material of a copper rectangular wire having a relatively large cross-sectional area (for example, a cross-sectional area of about 10 mm ² or more) from the following points (A) to (D). be able to. In particular, since the copper coil material of the embodiment has high elongation and excellent workability, a copper rectangular wire excellent in shape accuracy and dimensional accuracy can be produced by using the copper coil material for the material.
(A) Since it has a high elongation, it is excellent in workability of rolling (flattening) for deforming into a flattened shape.
(B) Since the cross-sectional area is in a specific range and the mass is sufficiently large, it can be said that the copper wire is sufficiently long, and the copper rectangular wire can be mass-produced because it is long.
(C) Since the cross-sectional area is in a specific range, a copper rectangular wire having a large cross-sectional area can be formed.
(D) Since the lubricating layer is provided, the lubricating layer can be used as a lubricating material when rewinding and feeding out the lubricating material and the copper coil material when winding the copper wire. In addition, the lubricating layer can be used as a lubricant for flattening the unwound copper wire, and the flattening can be performed with high accuracy.

Moreover, the copper coil material of the embodiment is excellent in productivity from the following points (a) to (d).
(A) For example, since it can be manufactured by winding a long copper wire obtained by subjecting a continuous cast rolled material (copper rough drawing wire) to conform extrusion, both the wire drawing step and the heat treatment step are unnecessary. The number of manufacturing processes is small.
(B) Since it is not necessary to consider the degree of wire drawing by using conform extrusion, it is not necessary to use a thick copper rough wire, and a general-purpose copper rough wire can be used.
(C) A long material can be easily manufactured by utilizing continuous casting and rolling and conform extrusion.
(D) Since the lubricating layer is provided, the slipperiness is excellent, so that the copper wire is easily wound during winding, and the copper wire is hardly scratched.

When the copper coil material of the embodiment is manufactured through conform extrusion, the surface properties are excellent and the elongation tends to be further increased from the following points. Furthermore, it is easy to become a copper coil material excellent not only in elongation but also in strength. This copper coil material is further excellent in workability of rolling (flattening), and can be suitably used for a copper flat wire material, particularly a copper flat wire material having a large cross-sectional area.
A new surface free from surface defects can be formed by plastic deformation based on extrusion.
-It becomes a processed structure (fine crystal structure) composed of fine crystal grains by dynamic recrystallization during extrusion.
-Plastic deformation or dynamic recrystallization during extrusion reduces surface defects and coarse grains that can be the starting point of cracks and fractures, and tends to form crystals of uniform size.

  (2) As an example of the copper coil material according to the embodiment, a form in which the average crystal grain size of the copper wire is 5 μm or more and 40 μm or less can be given.

  In the above-mentioned form, the copper wire is composed of a fine crystal structure, so that it is excellent in elongation and surface properties, and is excellent in workability of rolling (flat angle processing). Therefore, by using the copper coil material of the above-described form as a material for a copper flat wire, a copper flat wire having excellent shape accuracy and dimensional accuracy and excellent surface properties can be produced with high productivity.

  (3) As an example of the copper coil material according to the embodiment, there is a form in which the tensile strength of the copper wire is 230 MPa or more.

  Since the said form is high in elongation and excellent in strength, it is excellent in workability of rolling (flat angle processing). Therefore, when the copper coil material having the above-described form is used as a material for a copper flat wire, cracks and breakage are hardly generated, and a copper flat wire can be manufactured with high productivity.

  (4) The copper flat wire according to the embodiment is manufactured by rolling the copper wire material obtained by rewinding the copper coil material according to any one of the above (1) to (3). Yes.

Since the copper rectangular wire of the embodiment is made of a copper coil material having a specific cross-sectional area, it can have a relatively large cross-sectional area (for example, about 10 mm ² or more). Moreover, since the copper rectangular wire of embodiment uses the copper coil material with high elongation as a raw material, elongation is high. Furthermore, since the copper rectangular wire of the embodiment is made of the copper coil material of the embodiment having high elongation and excellent workability of rolling (flattening), the shape accuracy and dimensional accuracy are also excellent. Due to the excellent workability, cracks and breaks are less likely to occur during the flat processing, and the copper rectangular wire of the embodiment is also excellent in productivity. When the copper coil material is manufactured through conform extrusion, since the copper coil material having excellent surface properties is used as the material, the copper rectangular wire of the embodiment is also excellent in surface properties. The copper rectangular wire of such an embodiment can be suitably used for a conductor of a coil winding.

  (5) The covered rectangular wire according to the embodiment includes a conductor made of the copper rectangular wire of the above-described embodiment and an insulating coating formed on the surface of the conductor.

  The coated rectangular wire according to the embodiment includes the copper rectangular wire according to the embodiment excellent in elongation in the conductor, so that bending such as winding can be easily performed, and it can be suitably used for winding the coil. When the copper rectangular wire of the embodiment having excellent surface properties is used as a conductor, the coating does not easily swell when the coating is formed, and the coated rectangular wire of the embodiment is also excellent in productivity.

(6) The manufacturing method of the copper coil material which concerns on embodiment is equipped with the following preparatory processes, an extrusion process, and a winding process.
(Preparation process) The process of preparing a continuous cast rolling material.
(Extrusion step) A step of producing a copper wire by subjecting the continuous cast rolled material to conform extrusion.
(Winding process) The process of manufacturing a copper coil material by winding in a coil shape after forming a lubrication layer on the surface of the said copper wire.
The said copper coil material is used for the raw material for giving a rolling process to the said rolled copper wire, and manufacturing a copper flat wire.

  The manufacturing method of the copper coil material of the embodiment is a copper coil material (typically the copper coil material of the above-described embodiment) that has high elongation and excellent surface properties in terms of the following (ii) and (ii). Can be manufactured. Moreover, the manufacturing method of the copper coil material of embodiment can manufacture such a copper coil material with high productivity from the following ((alpha))-((epsilon)) point.

(Ii) Fine and uniform crystal grains can be formed by dynamic recrystallization during extrusion.
(Ii) A new surface free from surface defects can be formed by plastic deformation based on extrusion.

(Α) Both the wire drawing step and the heat treatment step are unnecessary, and the number of manufacturing steps is small.
(Β) Since a copper wire having various cross-sectional areas can be easily manufactured by adjusting the extrusion conditions, as a continuous cast rolled material, a material having a general size can be used as well as a thick material.
(Γ) Both continuous casting and rolling and conform extrusion can easily produce a long material.
(Δ) The continuously cast rolled material has a fine crystal structure by dynamic recrystallization and is excellent in plastic workability such as conform extrusion, so it is difficult to overload during extrusion, It can be done well.
(Ε) Since the lubricating layer is excellent in slipperiness, it is easy to wind up the copper wire during winding, and it is difficult to scratch the copper wire.

In particular, the copper coil material manufacturing method of the embodiment is capable of manufacturing a copper coil material having a high elongation of 30% or more without breaking the wire drawing step and the heat treatment step after continuous casting and rolling. Industrial significance is high. Moreover, the copper coil material manufactured by the copper coil material manufacturing method of the embodiment can be suitably used for a material of a copper flat wire having a relatively large cross-sectional area (for example, a cross-sectional area of about 10 mm ² or more). it can. Since a copper flat wire can be easily and highly accurately manufactured by unwinding the copper coil material and subjecting the copper wire material to rolling (rectangular processing), the copper coil material manufacturing method of the embodiment is It can be said that it can contribute to productivity improvement.

(7) As an example of the method for producing a copper coil material according to the embodiment, the cross-sectional area of the continuous cast rolled material is 50 mm ² or more and 750 mm ² or less, and the cross-sectional area of the copper wire is 12 mm ² or more and 40 mm ² or less. A form is mentioned.

In the above embodiment, since both the continuous cast rolled material and the copper wire have a sufficient size, copper suitable for a material of a copper rectangular wire having a relatively large cross-sectional area (for example, a cross-sectional area of about 10 mm ² or more). The coil material can be manufactured with high productivity.

(8) The manufacturing method of the copper flat wire which concerns on embodiment is equipped with the following preparatory processes, an extrusion process, a winding process, and a rolling process.
(Preparation process) The process of preparing a continuous cast rolling material.
(Extrusion step) A step of producing a copper wire by subjecting the continuous cast rolled material to conform extrusion.
(Winding process) The process of manufacturing a copper coil material by winding in a coil shape after forming a lubrication layer on the surface of the said copper wire.
(Rolling process) The process which unwinds the said copper coil material, gives a rolling process to the said copper wire, and manufactures a copper flat wire.

  The method for producing a copper rectangular wire according to the embodiment can produce a copper coil material that has high elongation and excellent surface properties from the above points (Α), (Β), and (α) to (ε) with high productivity. By using a copper coil material as a raw material, a copper rectangular wire having high elongation and excellent surface properties can be produced with high productivity. In particular, in the method for producing a copper flat wire according to the embodiment, after the conform extrusion, the lubricating layer is formed before the copper wire is wound, so that the copper wire can be easily wound, and the lubricating layer is formed as described in (D) above. Thus, since it can utilize as a lubrication material for the next rolling process (flat angle process), the productivity of a copper rectangular wire can be improved more. Here, in a copper wire that has been heat-treated after wire drawing, even if a lubricant is applied to the wire-drawn material, the lubricant is burned away by the heat treatment. For this reason, when the heat-treated wire drawing material is used as a copper flat wire material, the slipperiness at the time of unwinding or flat work may be insufficient. Since the manufacturing method of the copper rectangular wire of the embodiment can improve the slipperiness by the lubricating layer, compared with the case where the heat-treated wire drawing material is used for the copper rectangular wire material, the material (copper wire material of the embodiment) is used. Flat angle processing can be performed with higher accuracy. As a result, the method for producing a copper rectangular wire according to the embodiment can produce a copper rectangular wire excellent in shape accuracy and dimensional accuracy with high productivity while suppressing the occurrence of shape failure and dimensional failure.

[Details of the embodiment of the present invention]
Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings as appropriate. The copper coil material, the copper rectangular wire, and the covered rectangular wire will be described in this order, and then the manufacturing method will be described.

[Copper coil material]
The copper coil material 1 of the embodiment is obtained by winding a long copper wire 10 in a coil shape as shown in FIG. 1 and is used as a material for a copper rectangular wire. The copper wire 10 includes a lubricating layer 12 on the surface thereof. The lubrication layer 12 is interposed between turns formed by the wound copper wire 10. Therefore, when the copper wire 10 is unwound and fed out, the lubricating wire 12 makes the copper wire 10 slip easily, that is, the copper coil material 1 is excellent in slipperiness and is easy to feed out. Hereinafter, the copper wire 10 which is the main body of the copper coil material 1 will be described first.

(composition)
The constituent material of the copper wire 10 is so-called pure copper or a copper alloy (including additive elements, with the balance being Cu and inevitable impurities). Pure copper includes, for example, oxygen-free copper (Cu content is 99.95% by mass or more, oxygen content is 0.005% by mass or less), tough pitch copper (Cu content is 99.90% by mass or more), phosphorus deoxidation Copper (for example, Cu content is 99.90 mass% or more, P content is less than 0.015 mass%), etc. are mentioned. The additive element of the copper alloy is, for example, at least one element of tin (Sn), nickel (Ni), silicon (Si), iron (Fe), phosphorus (P), silver (Ag), and chromium (Cr). Can be mentioned. The content of each element is, for example, 0.05% by mass or more and 1% by mass or less. When a plurality of additive elements are included, the total content is 0.1% by mass or more and 6% by mass or less. It is done. Pure copper is easy to obtain a copper wire 10 or a copper flat wire with high elongation and electrical conductivity. A copper alloy is easy to obtain the copper wire 10 and copper flat wire which are excellent in intensity | strength.

  In addition, the constituent material of the continuous cast rolling material used for the manufacturing method of the copper rectangular wire of embodiment, the copper coil material of embodiment, etc. is also made into the above-mentioned pure copper or copper alloy.

(Organization)
The copper wire 10 typically has a form constituted by fine crystals over substantially the entire region from the surface to the inside. In particular, it is preferable that the average crystal grain size of the copper wire 10 is 40 μm or less because elongation and strength are likely to be high and workability is excellent. For example, when the copper wire 10 is subjected to rolling (flattening), the entire copper wire 10 is uniformly deformed and hardly breaks, and this form makes it possible to produce long copper flat wires. Can be manufactured well. The smaller the average crystal grain size of the copper wire 10 is, the smaller the average grain size, the better the elongation and the better the workability of flattening. Therefore, it is preferably 30 μm or less, more preferably 20 μm or less. The crystal grain size of the copper wire 10 can typically be adjusted by the extrusion conditions. For example, if the degree of extrusion is increased, the crystal grain size can be easily reduced. If the degree of extrusion is increased too much, that is, if the load during extrusion is increased too much, extrusion becomes difficult and the productivity of the copper coil material 1 is reduced. Accordingly, the average crystal grain size of the copper wire 10 is preferably 5 μm or more, and is preferably 7 μm or more, and more preferably 10 μm or more, considering the workability of flattening and the processability during extrusion.

  The crystal grain size of the copper wire 10 is measured by a cross section obtained by cutting the copper wire 10 along a plane parallel to the axial direction, a so-called longitudinal section, or a cross section obtained by cutting the copper wire 10 by a plane perpendicular to the axial direction, so-called transverse. Take a plane and use this section. When the copper wire 10 is manufactured through conform extrusion, a granular structure can be confirmed in both the longitudinal section and the transverse section, and therefore, both the longitudinal section and the transverse section can be used for the measurement of the crystal grain size. . Details of the measurement method will be described later.

(shape)
The copper wire 10 can have various external shapes (cross-sectional shapes) depending on manufacturing conditions. In particular, when the copper wire 10 is a round wire having a circular cross section, (1) it is easy to extrude by conform extrusion or the like, and it is easy to produce a material that is excellent in shape accuracy and dimensional accuracy, and that is also excellent in surface properties. ) Easy to form the lubricating layer 12 to a uniform thickness, (3) Easy to wind up, (4) Easy to uniformly apply rolling (flattening), easy to obtain a rectangular wire with excellent shape accuracy and dimensional accuracy And so on. When the copper wire 10 is manufactured through conform extrusion, it can be easily formed into a rectangular cross section, a polygonal shape, an elliptical shape, etc., but a round wire is preferable from the above-mentioned advantages.

(Cross sectional area)
The copper wire 10 can have various sizes depending on manufacturing conditions. The copper coil material 1 according to the embodiment is characterized in that the cross-sectional area of the copper wire 10 is large to some extent so that a copper rectangular wire having a relatively large cross-sectional area can be manufactured. Specifically, the cross-sectional area in the cross section of the copper wire 10 is 12 mm ² or more and 40 mm ² or less. When the copper wire 10 is a round wire, the wire diameter (diameter) is about 3.9 mm or more and 7.1 mm or less. When the cross-sectional area is 12 mm ² or more, the cross-sectional area can be suitably used for a copper rectangular wire material having a large cross-sectional area of about 10 mm ² or more. When the cross-sectional area is 40 mm ² or less, the copper wire 10 can be easily wound and fed out, and can be easily supplied to a flat-angle machining apparatus used in the next step. Sectional area of the copper wire 10, 12.5 mm ² or more 33.5 mm ² or less (6.5 mm or less than φ4mm in wire diameter), further 12.5 mm ² or more 28.5 mm ² or less (6mm inclusive φ4mm in wire diameter) It can be.

(mass)
Since the copper coil material 1 of the embodiment is a material for a copper rectangular wire, it is preferable that the copper coil material 1 is long so that the copper rectangular wire can be mass-produced by being continuously supplied to a rectangular processing apparatus. Since the mass of the copper coil material 1 increases as the copper wire material 10 becomes longer, the mass of the copper coil material 1 is preferably 50 kg or more. In the copper coil material 1 of the embodiment, the mass is 100 kg or more. Although depending on the composition of the copper wire 10 and the size of the cross-sectional area, when the mass of the copper coil material 1 is 100 kg or more, the length of the copper wire 10 is, for example, 350 m or more. The mass of the copper coil material 1 can be 150 kg or more (for example, 500 m or more), 200 kg or more (for example, 700 m or more), and further 300 kg or more (for example, 1000 m or more). The upper limit of the mass of the copper coil material 1 is not particularly set, but if it is 5000 kg or less, and further 2000 kg or less, it is expected that the copper coil material 1 can be easily supplied to a general-purpose flat-angle machining apparatus or can be conveyed.

(Surface properties)
The copper wire 10 is typically manufactured through at least one plastic processing after casting, so that it has few or substantially no surface defects such as cracks and is excellent in surface properties. For example, when manufactured using a continuously cast rolled material, surface defects (sink marks, surface cracks, blowholes, etc.) generated in the casting process are removed by rolling, or fine crystals are obtained by dynamic recrystallization. It becomes easy to become the copper wire 10 which is excellent in surface property by becoming a structure | tissue. In particular, when the copper wire 10 is manufactured through conform extrusion, a new surface is formed at the time of extrusion, and surface defects such as cracks are eliminated, so that the copper wire 10 is excellent in surface properties. Even if it becomes a fine crystal structure as described above by plastic working or the like (for example, the average crystal grain size is 40 μm or less), the copper wire 10 is excellent in surface properties.

(Mechanical properties)
The copper wire 10 is characterized by high elongation. Specifically, the copper wire material 10 has a breaking elongation at room temperature of 30% or more. In particular, when the copper wire 10 is manufactured through conform extrusion, the copper wire 10 can have a high elongation over the entire length of the copper wire 10. That is, in the typical form of the copper coil material 10 of the embodiment, the elongation at break is measured at an arbitrary position in the longitudinal direction, and the elongation is as high as 30% or more. Depending on the composition and manufacturing conditions of the copper wire 10, the elongation at break at room temperature may be 35% or more, and more preferably 40% or more.

  As an example of the copper wire 10, a form excellent in strength, for example, a form satisfying a tensile strength at room temperature of 230 MPa or more can be mentioned. The copper wire 10 is typically such a high-strength material because it is excellent in surface properties as described above or is composed of a fine crystal structure. Depending on the composition and manufacturing conditions of the copper wire 10, the tensile strength at room temperature may be 240 MPa or more, and more preferably 245 MPa or more. Thus, by using the copper wire 10 that is excellent not only in elongation but also in strength, a copper rectangular wire that is excellent in mechanical properties such as elongation and strength can be obtained.

(conductivity)
Since the copper wire 10 is comprised by pure copper or a copper alloy as mentioned above, it can have high electrical conductivity. Although it depends on the composition and manufacturing conditions of the copper wire 10, examples include a form in which the electrical conductivity of the copper wire 10 at room temperature satisfies 98% IACS or more, further 99% IACS or more, and further 100% IACS or more.

(Lubrication layer)
One of the features of the copper wire 10 is that it has a lubricating layer 12 on its surface. The lubricating layer 12 is formed before the copper wire 10 is wound, and has a function of improving the slipperiness when the copper wire 10 is wound and a function of improving the slippery when the copper coil material 1 is unwound and fed out. . Furthermore, the lubricating layer 12 can be used to enhance the slipperiness when the copper wire 10 is subjected to rolling (flat angle processing). The lubricating layer 12 can be selected from various materials and thicknesses that exhibit these functions.

  Examples of the lubricant constituting the lubricating layer 12 include a mixture of one or more oils selected from mineral oil, synthetic oil, vegetable oil, and the like, and a surfactant, and those mainly composed of fats and soaps. It is done. Specifically, Lubrite (registered trademark) manufactured by Nippon Oil Research Laboratory Co., Ltd., model number Lubro30FM manufactured by Richards Apex Co., Ltd., D.C. A. Examples include model number WM561 manufactured by Stuart Corporation. A well-known lubricant used for copper wire can be used.

As for the thickness of the lubricating layer 12, about 0.004 micrometer or more and 0.4 micrometer or less are mentioned, for example. By setting the adhesion amount of the lubricant on the surface of the copper wire 10 to about 0.5 μg / cm ² or more and 50 μg / cm ² or less, the thickness can be in the above range. Further more 0.007μm thickness of the lubricating layer 12 0.07 .mu.m or less, deposition amount can be 0.9 [mu] g / cm ² or more 9 [mu] g / cm ² or less. When the lubricating layer 12 is thick in the above-mentioned range and has a large amount of adhesion, the slipperiness during winding and unwinding and the workability during rolling are excellent. If the lubricating layer 12 is thin in the above-mentioned range and the amount of adhesion is small, it can be prevented from collapsing during storage or transportation and easy to handle. A method for forming the lubricating layer 12 will be described later.

(Use)
The copper coil material 1 according to the embodiment can be suitably used as a copper flat wire material, specifically, a copper flat wire material formed by unwinding the copper coil material 1 and subjecting it to a rolling process (flat square processing). it can. In addition, the copper coil material 1 can be used as a material for various conductive members such as conductors of electric wires.

[Copper flat wire]
The copper rectangular wire of the embodiment is manufactured by using the copper coil material 1 (copper wire material 10) of the above-described embodiment as a raw material, rolling the raw material (flat rectangular processing), and forming the cross-sectional shape into a rectangular shape. It has been done.

(Organization)
The copper rectangular wire of the embodiment has a structure similar to that of the copper wire 10 from the above-described manufacturing method. That is, this copper rectangular wire is typically configured with a fine crystal structure comparable to the copper wire 10 or a finer crystal structure than the copper wire 10.

(shape)
The copper rectangular wire of the embodiment has a rectangular shape in cross section, typically a flat shape in which the ratio of the width w to the thickness t (w / t) is more than 1, that is, a shape having a width wider than the thickness. It is. The ratio (w / t) can be selected as appropriate, and can be 1.5 or more, further 2 or more, and further 2.5 or more. In addition, depending on rolling conditions, a copper rectangular wire can be made into the square-shaped square wire whose said ratio (w / t) is 1.

(size)
The cross-sectional area, width w, and thickness t of the copper rectangular wire of the embodiment can be easily changed depending on the rolling conditions. In particular, as the copper flat wire embodiments, the cross-sectional area extent 5mm ² or 100 mm ² or less, the thickness t is much more 5mm or less 0.5 mm, the width w is much more 20mm or less 1 mm, and the like. By using a copper rectangular wire having such a relatively large cross-sectional area as a conductor of a coil winding, a high output coil can be provided. The cross-sectional area can be about 10 mm ² . Depending on the rolling conditions, only the cross-sectional shape (outer shape) can be deformed without substantially changing the cross-sectional area.

(Mechanical properties / conductivity)
The copper rectangular wire according to the embodiment tends to be increased in strength by work hardening by subjecting the above-described copper wire 10 to plastic processing such as rolling (flat rectangular processing). Therefore, the copper flat wire of the embodiment includes a form in which the tensile strength at room temperature is higher than that of the copper wire 10 described above. On the other hand, elongation and electrical conductivity tend to be lowered due to processing strain based on the above-described flat processing. Therefore, the copper flat wire of the embodiment includes a form in which at least one of elongation at break and electrical conductivity at room temperature is lower than that of the copper wire 10 described above.

(Use)
The copper rectangular wire according to the embodiment is excellent in elongation and strength and can be easily used for a conductor of a coil winding because it can be easily wound. When the copper rectangular wire of the embodiment is used as a conductor, it may be used as it is (used as a bare wire), or may be used as a covered rectangular wire having an insulating coating formed on the surface thereof. In addition, the copper rectangular wire can be used for various conductive members by cutting it into an appropriate length or by deforming it into a desired shape by pressing or the like.

[Coated rectangular wire]
The coated rectangular wire of the embodiment includes the copper rectangular wire 20 (FIG. 3) of the above-described embodiment as a conductor, and further includes an insulating coating (not shown) on the surface of the conductor.

(conductor)
The conductor included in the coated rectangular wire of the embodiment substantially maintains the composition, shape, and size of the copper rectangular wire of the above-described embodiment. Therefore, this conductor typically has a flat rectangular shape with a cross-sectional area of about 5 mm ² or more and 100 mm ² or less and the above-mentioned ratio (w / t) is more than 1. The cross-sectional area of the conductor can be about 10 mm ² , the thickness can be about 0.5 mm to 5 mm, and the width can be about 1 mm to 20 mm. As this conductor, the copper rectangular wire of the embodiment is subjected to a heat treatment for the purpose of removing processing strain or the like. Since elongation and electrical conductivity can be improved by applying heat treatment, the coated rectangular wire of the embodiment includes a form in which at least one of elongation at break and electrical conductivity at room temperature is higher than the copper rectangular wire of the above-described embodiment. It is done. The coated rectangular wire of the embodiment is excellent in elongation, easy to perform operations such as winding, and excellent in conductivity, and can be suitably used for coil winding. In particular, when the coated rectangular wire of the embodiment includes the copper rectangular wire of the embodiment having the above-described large cross-sectional area, it can be suitably used for a high-power coil winding. Note that although the crystal grains grow slightly due to the heat treatment, if the crystal grains of the copper rectangular wire before the heat treatment are fine as described above, a fine crystal structure can be obtained even after the heat treatment.

(Insulation coating)
Examples of the material for the insulating coating include resins having excellent electrical insulation properties such as polyamideimide, polyimide, polyesterimide, polyurethane, and polyester. The thickness of the insulating coating may be selected according to desired withstand voltage characteristics. For example, the thickness of the insulating coating is about 0.01 mm (10 μm) to 0.5 mm (500 μm), and further 0.02 mm (20 μm) to 0.1 mm (100 μm).

[Manufacturing method of copper coil material]
The copper coil material 1 of the embodiment can be typically manufactured by subjecting a copper material to conform extrusion. By utilizing conform extrusion, (1) long copper wire 10 can be continuously manufactured (can be mass-produced), (2) copper wire 10 having high elongation can be manufactured, (3) plasticity during extrusion A copper wire 10 having excellent surface properties can be produced by forming a new surface by deformation. (4) Copper materials 10 of various sizes can be used, and copper wires 10 of various shapes and sizes can be produced (in copper materials) (5) The degree of freedom of size selection is large, the degree of freedom of selection of the shape and size of the copper wire 10 is large), (5) The crystal grains are refined by dynamic recrystallization during extrusion, and the fine crystal structure The copper wire 10 composed of the following is obtained. In particular, by using a copper material having a recrystallized structure, the copper material itself is excellent in extrusion processability, so that it is easy to obtain the copper wire 10 having excellent shape accuracy, dimensional accuracy, and surface properties. This form is characterized in that conform extrusion, which is a process capable of dynamic recrystallization, is applied to a copper material having a recrystallized structure. Examples of the copper material having a recrystallized structure include a cast material that has been subjected to processing such as rolling, wire drawing, extrusion, and forging. In particular, when a continuously cast and rolled material is used as the copper material having a recrystallized structure, the copper material can be mass-produced, thereby contributing to an improvement in the productivity of the copper wire 10. Then, in the manufacturing method of the copper coil material of embodiment, it is proposed to use a continuous cast rolling material as a copper material. Hereinafter, each process (a preparation process, an extrusion process, a winding process) with which the manufacturing method of the copper coil material of embodiment is equipped is demonstrated in order.

(Preparation process)
In this step, a continuous cast rolled material 100 (FIG. 3) that is a copper material is prepared. The continuously cast rolled material 100 can be manufactured by using equipment capable of performing a rolling process subsequent to continuous casting. Examples of the continuous casting include a twin belt method, a belt-and-wheel method, and a horizontal drawing method. Examples of the continuous casting and rolling include a continuous rod method, a propelty method, and an SCR (Southern Continuous Rod) method. Commercially available continuous cast rolled material (copper rough wire) can be used.

The shape and size (wire diameter, cross-sectional area, length, etc.) of the continuously cast rolled material can be appropriately selected. The continuous cast rolled material 100 typically includes a round wire having a circular cross section. Moreover, it is preferable that the continuous cast rolled material 100 has a cross-sectional area that can make the cross-sectional area of the copper wire 10 after conform extrusion 12 mm ² or more. In particular, when the cross-sectional area of the continuously cast rolled material 100 is 50 mm ² or more (in the case of a round wire, φ 7.98 mm or more in terms of wire diameter), the copper wire 10 having a cross-sectional area of 12 mm ² or more can be manufactured. In addition, since it includes a size that can be manufactured by a general-purpose device, it is excellent in productivity of the continuously cast rolled material 100 and can contribute to improvement in productivity of the copper wire 10. If the continuous cast rolled material 100 is too large, the productivity is lowered. Therefore, the cross sectional area of the continuous cast rolled material 100 is preferably 750 mm ² or less (about φ30 mm or less in terms of wire diameter). The cross-sectional area of the continuous casting and rolling material 100 700 mm ² or less (less than about φ30mm in diameter conversion), further 365 mm ² or less (less than about φ22mm in diameter equivalent), even 270 mm ² or less (less than about φ19mm in diameter conversion) It can be. If the cross-sectional area of the continuously cast rolled material 100 is 150 mm ² or less (less than about φ15 mm in terms of wire diameter) and further 140 mm ² or less (about φ13.5 mm or less in terms of wire diameter), (1) it can be easily manufactured with a general-purpose device. It is more excellent in productivity of continuously cast rolled material, and can contribute to further improvement in productivity of copper wire 10. (2) It is difficult to curl and is subjected to rolling (flat angle processing). At this time, there is an advantage that the removal of the curl or the processing for improving the straightness can be omitted, and the productivity of the copper rectangular wire 20 can be improved.

(Extrusion process)
This step is a step of manufacturing the copper wire 10 by subjecting the prepared copper material (continuously cast rolled material 100) to conform extrusion. A commercially available conform extrusion apparatus can be used for the conform extrusion. Hereinafter, the conform extrusion apparatus and the extrusion principle will be described with reference to FIG.

  The conform extrusion apparatus 200 includes a cylindrical wheel 210 that is rotatably supported, and a groove 212 that is provided in a circumferential direction of the wheel 210 and in which a wire rod (here, the continuous cast rolled material 100) serving as a material is disposed. A shoe 220 that covers a part of the opening of the groove 212 and functions as a lid, an abutment 232 attached to the groove 212 to dam the material, a die 234 for extruding the dammed material, and a die 234 And a die chamber 230 for housing.

  When the continuous cast rolled material 100 as the material is inserted into the groove 212 of the rotating wheel 210, the material is sequentially drawn by the frictional force between the wheel 210 and the material. The drawn material is blocked by the abutment 232, and the groove 212 is closed by the shoe 220, thereby generating an extrusion pressure. The extrusion pressure causes the material to flow into the material reservoir location (the location surrounded by the abutment 232 and the die 234) of the die chamber 230, and the die 234 is used to extrude the material into a desired shape and form the extruded material (here, A copper wire 10) can be produced. During extrusion, waste (burrs) 300 can be generated from the vicinity of the die 234.

  During extrusion, the material generates heat due to frictional heat and deformation heat. Therefore, a high temperature state (for example, 200 ° C. or higher) can be obtained without using a separate heating means. By being in a high temperature state, the plastic workability (extrudability) of the material can be improved. By separately preparing a cooling means and a heating means and adjusting the temperature of the die chamber 230 (die 234), a desired extruded state can be obtained. The obtained extruded material (copper wire 10) has a recrystallized structure due to dynamic recrystallization during extrusion and the above-described heat. Further, the copper wire 10 having a fine crystal structure by recrystallization has high elongation (breaking elongation of 30% or more) and is excellent in surface properties. Furthermore, this copper wire 10 is also excellent in strength (for example, tensile strength is 230 MPa or more). The copper coil material manufacturing method according to the embodiment is a material for a copper rectangular wire in that the copper wire material 10 having high elongation and the like can be manufactured without performing heat treatment such as wire drawing and softening after the extrusion. It can be said that the copper coil material 1 suitable for the production can be manufactured with good productivity.

The Conform extrusion, desired as size copper wire 10 can be obtained, preferably the cross-sectional area of 10 mm ² or more degrees of Dotaira rectangular wire 20 can be manufactured of 12 mm ² or more 40 mm ² or less of the cross-sectional with a large cross sectional area The size of the dice 234 is selected so that the copper wire 10 having an area can be obtained. In the conform extrusion, the size before and after the conform extrusion can be substantially unchanged or can be changed (the extruded material is larger than the material before the extrusion. Smaller ones can be extruded). That is, the cross-sectional area by conforming extrusion can be produced with 12 mm ² of less than copper wire and 40 mm ² than copper wire. Therefore, the manufacturing method of the copper coil material of the embodiment can be used for manufacturing a copper wire material having a cross-sectional area of less than 12 mm ² or more than 40 mm ² and high elongation is desired.

(Winding process)
This step is a step of manufacturing the copper coil material 1 by forming the lubricating layer 12 on the outer periphery of the copper wire 10 that has been subjected to conform extrusion and then winding it. For example, (1) when the copper wire 10 extruded into a predetermined shape is cooled before winding, the lubricant is added to the cooling medium in the cooling tank, and the copper wire is formed. 10 is immersed in a cooling bath to cool and adhere a lubricant, (2) a nozzle for spraying lubricant, a brush for application, a sponge containing lubricant, etc. are provided in front of the winder, and the nozzle For example, a method of adhering the lubricant to the copper wire 10 that passes in front of the winder by spraying the lubricant or boiling with a brush or sponge can be used. As a method for forming the lubricating layer 12, a known method for attaching a lubricating material to a wire can be used. The thickness of the lubricating layer 12 is adjusted by adjusting the concentration (addition amount) of the lubricant to the cooling medium, the immersion time in the cooling tank, the spraying pressure, the spraying time, the traveling speed of the copper wire 10, the pressing force of the brush, etc. (Adhesion amount) can be adjusted. For winding the copper wire 10, a known winder can be used. By providing the lubricating layer 12 on the surface of the copper wire 10, it is excellent in slipperiness during winding and easy to wind. If the cross-sectional area of the copper wire 10 is 40 mm ² or less, the rigidity is not too high and it is easier to wind.

[Manufacturing method of copper rectangular wire]
The copper flat wire 20 of the embodiment is manufactured by rewinding the copper coil material 1 of the above-described embodiment and subjecting the copper wire material 10 to rolling processing (flat wire processing) for deforming the copper wire material 10 into a rectangular cross section. can do. Then, as shown in FIG. 3, as a manufacturing method of the copper flat wire of embodiment, the above-mentioned preparatory process (preparation of the continuous cast rolling material 100), an extrusion process (preparation of the copper wire 10), a winding process (lubrication layer) It is proposed to include a rolling step (preparation of the copper flat wire 20) in addition to the production of the copper coil material obtained by winding the copper wire material 10 having 12. Hereinafter, the rolling process will be described, and since the preparation process, the extrusion process, and the winding process have already been described, detailed description thereof will be omitted.

(Rolling process)
This step is a step of manufacturing the copper rectangular wire 20 by subjecting the copper coil material 1 manufactured through conform extrusion to rolling (flattening) and changing the cross-sectional shape. The rolling conditions may be appropriately selected so as to obtain a copper rectangular wire 20 having a desired thickness, width, cross-sectional area, and the like. The copper wire 10 having a relatively large cross-sectional area in this rolling process is obtained by using the copper wire 10 having a high crystallinity and excellent workability as well as high elongation due to conform extrusion. Specifically, the copper rectangular wire 20 having a cross-sectional area of about 10 mm ² or more can be easily processed. Therefore, the copper rectangular wire manufacturing method of the embodiment can manufacture the copper rectangular wire 20 having the above-described large cross-sectional area with high productivity.

[Method for producing coated rectangular wire]
The coated rectangular wire of the embodiment includes, for example, a heat treatment step in which the above-described copper rectangular wire 20 is heat-treated to form a heat-treated wire, and a coating step in which the heat-treated wire is used as a conductor and an insulating coating is formed on the surface of the conductor. It can manufacture with a manufacturing method provided with.

  The main purpose of the heat treatment is to remove distortion introduced by rolling (flattening). By removing the strain, the elongation and the conductivity can be improved as described above. Examples of the heat treatment conditions include a heating temperature of about 100 ° C. to 550 ° C. and a holding time of about 0.2 seconds to 10 hours. Either a batch process or a continuous process may be used for the heat treatment. When continuous treatment is performed, heat treatment can be continuously performed on the long copper rectangular wire 20, and the holding time can be shortened. This heat treatment can be omitted.

  For the formation of the insulating coating, for example, a known technique used for manufacturing a known enameled wire can be used. Typically, the step of applying a resin constituting an insulating coating on the surface of the conductor, and the step of passing the conductor coated with the resin through a baking furnace and drying and curing the resin are baked. May be repeated one or more times until a predetermined thickness is reached.

[Test Example 1]
A wire made of pure copper was produced under various conditions, and the surface properties, structure, and mechanical properties of the obtained wire were examined. Moreover, the copper flat wire was produced from this wire, and also the covering flat wire provided with this copper flat wire as a conductor was produced, and the covering state was investigated.

Pure copper (tough pitch copper having a Cu content of 99.9% by mass or more) was prepared as a raw material to prepare a molten metal. Using the produced molten metal, a continuous cast rolling material (copper rough wire) having a circular cross section having a cross-sectional area (mm ² ) and a wire diameter φ (diameter, mm) shown in Table 1 is obtained by continuous cast rolling of a conti-rod system. Produced.

Sample No. 1-1-No. In 1-4, conform extrusion is performed on a copper rough drawn wire having a wire diameter of 9.5 mm to produce 100 kg of copper wire (conform extruded material) having a circular cross section (length: about 400 m, about 250 g / m), The coil was wound up. The extrusion conditions were an extrusion speed of about 12 m / min to 30 m / min, and a chamber temperature of about 200 ° C. to 300 ° C. The extrusion speed (m / min) was adjusted by the rotational speed of the wheel. The chamber temperature was adjusted by arranging a temperature adjusting mechanism (here, cooling means) in the vicinity of the die chamber and controlling the cooling state. Here, conform extrusion was performed with the target wire diameter of the copper wire set to 6 mm. Table 1 shows the cross-sectional area (mm ² ) and the wire diameter φ (diameter, mm) of the obtained copper wire. When winding the extruded copper wire into a coil shape to produce a copper coil material, a lubricant layer is formed by attaching a commercially available lubricant to the surface of the copper wire before winding the copper wire (coating amount: 3 μg). / Cm ² ), a copper wire provided with a lubricating layer was wound up.

  Sample No. 1-101, no. In 1-102, a thick copper rough wire having a wire diameter of φ18.5 mm was prepared. The thick copper rough wire is drawn to produce a wire with a circular cross section (target wire diameter φ6 mm). The thick wire is subjected to heat treatment, and the heat treated wire drawing material (hereinafter referred to as soft material). (Referred to as (thick)). The softening process was performed on the conditions of 240 degreeC x 3 hours using the batch furnace.

  Sample No. 1-201, no. In 1-202, a copper roughing wire having a wire diameter of φ8.0 mm was prepared. The copper rough wire is subjected to wire drawing to produce a wire having a circular cross section (target wire diameter φ3.2 mm). The thin wire is subjected to heat treatment, and the heat-treated wire drawing material (hereinafter referred to as soft wire). A material (referred to as “thin”) was prepared. The softening process was performed using a continuous processing furnace, and the conditions were adjusted so as to be sufficiently softened.

  The obtained sample No. 1-1-No. About 1-4 copper wire, surface observation by visual observation was performed. The results are shown in Table 1. When the surface defects such as cracks and wrinkles are not substantially recognized by visual confirmation, the surface properties are evaluated as good and the surface defects such as cracks of a size that can be visually confirmed are recognized as good. Evaluated to be inferior in properties and indicated as Bad. The surface observation was performed over the entire length of the test piece by extracting 50 m from an arbitrary position in the longitudinal direction of the produced 100 kg copper wire, using the 50 m long wire as a test piece.

  The obtained sample No. 1-1-No. 1-4 copper wire, Sample No. 1-101, no. 1-102 softwood (thick), sample no. 1-201, no. The soft material (thin) 1-202 was examined for tensile strength (MPa) at room temperature, elongation at break (%), and average crystal grain size (μm) in the longitudinal section. The results are shown in Table 1.

  Tensile strength and elongation at break were measured using a commercially available tensile tester by preparing a test piece according to JIS Z 2201 (1998). Here, the gauge distance GL = 250 mm. Here, three test pieces were prepared for each sample. Each test piece was produced by extracting the produced copper wire or soft material from an arbitrary position in the longitudinal direction. Table 1 shows the average values of the three test pieces for both tensile strength and elongation at break.

  The average crystal grain size was measured as follows. Taking a longitudinal section of each sample, observing an arbitrary position of the longitudinal section with an optical microscope or a scanning electron microscope (SEM), drawing a test line on the observed image, and counting the number of crystal grains that divide the test line. . Then, (the length of the test line / the number of crystal grains) is defined as the crystal grain size in the cross section. Here, the length of the test line was 3 mm. Further, here, three cross sections are taken for each sample, five test lines are drawn for each cross section, and the crystal grain size based on each test line is measured. Table 1 shows an average value of three cross sections, that is, an average value of crystal grain sizes based on a total of 15 test lines.

The obtained sample No. 1-1-No. 1-4 copper wire, Sample No. 1-101, no. 1-102 softwood (thick), sample no. 1-201, no. A copper flat wire was produced by subjecting a soft material (thin) 1-202 to rolling (flattening). Sample No. 1-1-No. The copper wire 1-4 was unwound and fed out of the copper coil material, and was supplied to the flat angle processing apparatus with the lubricating layer described above. Copper rectangular wires having a thickness t: 2 mm × width w: 5 mm, (w / t) = 2.5, and a cross-sectional area of 10 mm ² were prepared using a copper wire and a soft material (thick), respectively. A copper rectangular wire having a cross-sectional area of 3 mm ² was produced using a soft material (thin). Each copper flat wire thus produced was subjected to heat treatment, and then an insulation coating (polyimide, each sample had a thickness of 70 μm) was formed to obtain a coated flat wire using the copper flat wire as a conductor. Sample No. 1-1-No. 1-4, no. 1-101, no. The conditions for the heat treatment applied to the copper rectangular wire 1-102 were 400 ° C. × 30 seconds.

  About each produced covering flat wire, the generation | occurrence | production state of the covering swelling was investigated using the commercially available flaw detector. The results are shown in Table 1. Here, by placing a commercially available flaw detector alongside the coating forming facility and running a long wire (in this case, a coated flat wire), the number of occurrences of flaws (swells) in succession to the formation of the coating Can be counted (using an inline method).

  As shown in Table 1, sample Nos. Obtained by subjecting a continuous cast rolled material to conform extrusion. 1-1-No. It can be seen that the 1-4 copper wire has high elongation and excellent surface properties. Specifically, these copper wires have an elongation at break of 30% or more (here, 40% or more), have substantially no surface defects such as cracks, and have a smooth surface. Moreover, it turns out that these copper wire materials are comprised by the fine crystal structure. Specifically, these copper wires have an average crystal grain size of 40 μm or less. In addition, these copper wires are composed of fine and uniform crystal grains, and it has been confirmed that there are substantially no locally coarse crystal grains. Furthermore, it can be seen that these copper wires are excellent in strength in addition to elongation. Specifically, these copper wires have a tensile strength of 230 MPa or more (here, 245 MPa or more) and high strength. And these copper wire materials are sample No. which softened after drawing a comparatively thick copper rough drawing wire. 1-101, no. It can be seen that it has elongation and strength equal to or greater than those of the soft material (thick) 1-102.

  Sample No. 1-1-No. When the rolling process (flattening process) was applied to the copper wire 1-4, it was difficult to crack or break during rolling, and a copper rectangular wire having excellent shape accuracy and dimensional accuracy could be obtained (dimensional error ± 0). .005 mm). Furthermore, as shown in Table 1, the coated rectangular wires (samples No. 1-1 to No. 1-4) produced using this copper rectangular wire are unlikely to swell, and the rate of occurrence of bulging is very high. It turns out that it is low. One reason for this is that a copper wire that has high elongation and excellent surface properties due to the formation of a new surface is used as the material for the copper flat wire. This is considered to be because an excellent copper rectangular wire was obtained, and an air pocket based on surface defects was hardly formed. One of the reasons for this is that the copper wire provided with the lubrication layer was used as the material for the copper flat wire, so that the lubrication layer could be used as a lubricant during flat work and the flat work could be performed accurately. It is done. Sample No. 1-1-No. The copper wire 1-4 was provided with a lubricating layer, so that it was excellent in slipperiness even during rewinding or when supplied to a flat angle processing apparatus, and could be supplied satisfactorily.

From this, the cross-sectional area is 12 mm ² or more and 40 mm ² or less, the elongation at break is 30% or more, and the sample No. 1-1-No. It can be said that the 1-4 copper wire can be suitably used as a material for a copper rectangular wire having a relatively large cross-sectional area of about 10 mm ² .

And from this test, by subjecting a copper material such as a continuously cast rolled material to conform extrusion, a copper wire (sample No. 1-1 to 1-1) having high elongation (for example, elongation at break of 30% or more) and excellent surface properties. It can be seen that No. 1-4) can be manufactured. Moreover, this manufacturing method can manufacture the said copper wire which was completely softened, without performing a wire drawing process and heat processing after continuous casting rolling. Therefore, this manufacturing method uses the sample No. 1 that performs wire drawing and heat treatment. 1-101, no. It can be seen that the number of manufacturing steps is small compared to 1-102, and the copper wire can be manufactured with high productivity. In particular, in this test, Sample No. 1-1-No. For the production of the copper wire 1-4, a continuous cast rolled material having a general size of 50 mm ² or more and 150 mm ² or less is used, and the continuous cast rolled material itself is also excellent in productivity. Can be produced with high productivity. And it can be said that a copper flat wire can also be manufactured with high productivity by using the said copper wire for the raw material of a copper flat wire. Therefore, the manufacturing method of subjecting a copper material such as a continuously cast rolled material to conform extrusion can produce a copper wire suitable for a copper wire flat wire material having a relatively large cross-sectional area with high productivity, and consequently a relatively large cross-sectional area. It can be said that the copper rectangular wire can be manufactured with high productivity.

On the other hand, when a copper material having a breaking elongation of 30% or more is manufactured by performing wire drawing and heat treatment using a continuous cast rolled material having a general size, Sample No. 1-201, no. As is clear from the wire drawing material of 1-202 (heat treated, soft material (thin)), only those having a small cross-sectional area (here, 8 mm ² <12 mm ² ) can be obtained. That is, the soft material (thin) cannot be used as a material for a copper rectangular wire having a relatively large cross-sectional area of about 10 mm ² .

  On the other hand, when a thick continuous cast rolled material is used, a copper material having a breaking elongation of 30% or more (drawing materials of sample No. 1-101 and No. 1-102 ( With heat treatment, a soft material (thick) is obtained.However, this copper material = soft material (thick) requires wire drawing and heat treatment and is inferior in copper material productivity. When the coated wire is manufactured using thick), it can be seen that the coating swells more easily than Sample No. 1-1 to No. 1-4. Can be removed to some extent, but defects are likely to remain as compared with the copper wires of Sample No. 1-1 to No. 1-4 on which a new surface is formed, and scratches resulting from these remaining defects are present in the rectangular wire. It is thought to be because.

  The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the gist of the present invention. The present invention is shown by the scope of claims and is equivalent to the scope of claims. All changes within the meaning and scope are intended to be included. For example, composition / shape / cross-sectional area of continuous cast rolled material, composition / shape / cross-sectional area / structure of copper wire, crystal cross-sectional area / width / thickness of rectangular copper wire, constituent material of insulation coating, Thickness, extrusion conditions, etc. can be changed.

  The coated rectangular wire of the present invention is suitably used for windings of coils such as enameled wires used in automobiles, various household electric appliances, watches, etc., especially windings of automotive coil parts for which high output is desired. it can. The copper rectangular wire of this invention can be utilized suitably for the conductor of the said covered rectangular wire. The copper coil material of the present invention can be suitably used for the conductor material of the above-described coated rectangular wire and the material of the copper rectangular wire. The manufacturing method of the copper coil material of this invention can be utilized suitably for manufacture of a copper coil material (for example, the copper coil material of the said invention). The manufacturing method of the copper flat wire of this invention can be utilized suitably for manufacture of a copper flat wire (for example, the copper flat wire of the said invention).

DESCRIPTION OF SYMBOLS 1 Copper coil material 10 Copper wire material 12 Lubricating layer 20 Copper flat wire 100 Continuous casting rolling material 200 Conform extrusion apparatus 210 Wheel 212 Groove 220 Shoe 230 Die chamber 232 Abutment 234 Die 300 Scrap (burr)

Claims (7)

A copper wire composed of pure copper or a copper alloy is wound into a coil,
The cross-sectional area of the copper wire is 12 mm ² or more and 40 mm ² or less,
The elongation at break of the copper wire is 30% or more,
The mass is 100 kg or more,
A lubricating layer is provided on the surface of the copper wire,
Copper coil material used as a material for rolling to produce copper flat wire.   The copper coil material according to claim 1, wherein an average crystal grain size of the copper wire is 5 µm or more and 40 µm or less.   The copper coil material according to claim 1 or 2, wherein the copper wire has a tensile strength of 230 MPa or more. Preparing a continuously cast rolled material;
A step of producing a copper wire by subjecting the continuous cast rolled material to conform extrusion;
Forming a lubricating layer on the surface of the copper wire, and then winding the coil to produce a copper coil material,
The said copper coil material is a manufacturing method of the copper coil material used for the raw material for giving the rolling process to the said copper wire material which wound up, and manufacturing a copper flat wire. The cross-sectional area of the continuous cast rolled material is 50 mm ² or more and 750 mm ² or less,
The method for producing a copper coil material according to claim 4 , wherein a cross-sectional area of the copper wire is 12 mm ² or more and 40 mm ² or less. Preparing a continuously cast rolled material;
A step of producing a copper wire by subjecting the continuous cast rolled material to conform extrusion;
After forming a lubricating layer on the surface of the copper wire, a step of winding a coil to produce a copper coil material,
Rewinding the copper coil material, rolling the copper wire material, and producing a copper rectangular wire.   Applying a heat treatment to the copper rectangular wire produced by the method for producing a copper rectangular wire according to claim 6;
  And a step of forming an insulating coating on the outer periphery of the wire subjected to the heat treatment.

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