JP2013052434A - Method for manufacturing copper stock for wire rod - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a copper stock for a wire rod which contributes to improvement of productivity of the wire rod by reducing disconnection and surface defects of the wire rod when manufacturing a copper-based wire rod made of copper or copper alloy, the copper stock for the wire rod, the copper based wire rod, and a method for manufacturing the copper based wire rod.SOLUTION: Scalping is carried out by using a scalping die 100 to a bar-shaped stock 10 made of the copper or the copper alloy, and subjected to at least casting thereto. The scalping satisfies at least any one of the conditions of (A)-(C): (A) the removal amount by scalping is 1-10% by the sectional area ratio; (B) the drawing degree before the scalping is drawing of 15-75%; and (C) the rake angle θ of a cutting blade 120 is 2-5°. The copper-based wire rod is manufactured by applying drawing to the obtained scalped material until the desired final wire diameter is obtained. By applying the scalping to the bar-shaped stock 10 under the specified condition, the copper stock for the wire rod having excellent surface property is obtained. By applying drawing to the stock, the copper-based wire rod which is hardly disconnected during the drawing and excellent in surface property can be manufactured with high productivity.

Description

  TECHNICAL FIELD The present invention relates to a method for producing a copper material for a wire made of copper or a copper alloy and used as a material for a wire drawing material (copper base wire), a copper material for a wire, a copper base wire, and a method for producing a copper base wire. In particular, the present invention relates to a method for producing a copper material for a wire, which can reduce a disconnection at the time of wire drawing and can produce a copper material for a wire that can be obtained with good productivity from a copper base wire having excellent surface properties.

  Conventionally, copper base wires made of copper or copper alloys having excellent conductivity have been used for conductor wires such as various power supply wires.

  A copper base wire is typically obtained by subjecting a cast material to wire drawing until a desired final wire diameter is obtained (Patent Document 1, etc.). For the production of a cast material, a copper base wire material can be produced with high productivity by using a continuous casting method capable of continuously producing a long material (Patent Document 1).

JP 2010-046710 A

  Improvement of the productivity of copper base wire is desired.

  In order to improve the productivity of the copper base material, it is effective to reduce surface defects of the material (typically, a rod-shaped cast material, for example, a continuous cast material). In the manufacturing process of this material, defects due to the material itself such as blow holes generated in the ingot, entrainment of an oxide film formed on the surface of the ingot, and surface cracks generated in the solidification process may occur. In particular, such a defect tends to occur in a continuous cast material. If there are surface defects in the material used for wire drawing, the tensile strength of the defective part will be relatively lower than normal parts other than the defective part, and the wire will not be able to withstand the pulling force during wire drawing. It becomes difficult to obtain long materials. Even if the wire breakage does not occur, a wire rod having inferior dimensional accuracy, shape accuracy, and appearance can be obtained by deformation or surface defects remaining. Also, if surface defects remain after wire drawing, or if the copper base wire is a trolley wire or the like, this defect becomes the starting point of breakage, leading to a decrease in strength and fatigue characteristics, conductors for covered wires, etc. In such a case, the adhesion between the conductor and the insulating coating may be inferior. Thus, if the material provided upstream of the manufacturing process has a surface defect, it is possible to obtain a long copper base material excellent in dimensional accuracy, shape accuracy, appearance, adhesion to insulating coating, mechanical properties, etc. Difficult, causing a drop in the productivity of the copper base wire.

  Then, one of the objectives of this invention is providing the manufacturing method of the copper raw material for wires which can manufacture the copper raw material for wires which can manufacture a copper base wire with high productivity. Moreover, the other objective of this invention is to provide the copper raw material for wires which can contribute to the improvement of the productivity of a copper base wire. Furthermore, the other object of this invention is to provide the copper base wire which is excellent in surface property, and its manufacturing method.

  The present inventors have studied various methods for removing surface defects of a copper material for a wire used as a material for a copper base wire. As a result, before performing the wire drawing until the final wire diameter (hereinafter referred to as the main processing), the skin is peeled off under specific conditions, and the main material is applied to the stripping material to obtain surface properties. The present inventors have obtained knowledge that an excellent and long copper base wire can be manufactured, that is, a copper base wire can be manufactured continuously with a reduced frequency of disconnection. Based on this knowledge, the present invention proposes to perform skinning under specific conditions when manufacturing a copper material for wire.

The method for producing a copper material for a wire according to the present invention relates to a method for producing a copper material for a wire used as a material for a copper base wire subjected to wire drawing, and is made of copper or a copper alloy, It includes a preparation process for producing a bar-shaped material that has been cast at least, and a skinning process for skinning the bar-shaped material. The skinning step satisfies at least one of the following (A) to (C).
(A) The removal amount by the above-mentioned skinning process shall be 1% or more and 10% or less in terms of the sectional area ratio.
(B) The above stripping process is performed on a pre-processed material obtained by subjecting the rod-shaped material to a wire drawing of 15% or more and 75% or less in the degree of wire drawing.
(C) The rake angle of the cutting edge of the skinning die used for the skinning process is 2 ° or more and 50 ° or less.

  When removing surface defects by skinning the rod-shaped material, if the amount of removal is small (removed thickness is thin), surface defects may remain, so the amount of removal is greatly increased (removed) It is conceivable that the thickness is made very thick). However, if the amount of removal by one peeling is too much, it becomes difficult to uniformly control the removal thickness in the circumferential direction of the rod-shaped material, and new defects may be caused by uneven cutting, or when peeling There is a risk of disconnection and a decrease in accuracy of shape and wire diameter. In addition, an excessive amount of removal reduces the yield, and as a result, decreases the productivity of the copper base wire.

  The manufacturing method of the present invention having the above configuration suppresses a decrease in yield by performing specific skinning in which at least one of the removal amount, the specification of the cutting blade to be used, and the pretreatment conditions is in a specific range. On the other hand, it is possible to suppress the disconnection at the time of peeling and to manufacture a copper material for a wire rod with reduced surface defects with high productivity. In addition, the copper material for wire of the present invention obtained by the method for producing a copper material for wire of the present invention is excellent in surface properties, so that the copper base material for wire is subjected to wire drawing (main processing). When manufacturing, it is hard to break and can be continuously drawn, so that a long copper base wire can be manufactured. Moreover, the obtained copper base wire has few surface defects and excellent surface properties. Therefore, this copper base wire material is (1) excellent in mechanical properties with reduced strength and fatigue properties due to surface defects, (2) excellent in dimensional accuracy, shape accuracy and appearance, (3) insulation Excellent adhesion to the coating. Therefore, the manufacturing method of the copper material for wire of the present invention and the copper material for wire of the present invention can contribute to the improvement of the productivity of the copper base wire having excellent surface properties.

  As one form of the manufacturing method of the copper raw material for wire rods of the present invention, a form in which the rod-shaped raw material is a continuously cast rolled material can be mentioned.

  By making the said rod-shaped raw material into a continuous casting material, productivity of the copper raw material for wires can be improved. Furthermore, if rolling is continuously performed without winding up the continuous cast material, and the continuous cast rolled material is used as the material of the copper base material, work hardening and refinement of crystals are achieved compared to the cast material that has not been rolled. It is possible to improve the strength by reducing the cracks on the surface of the cast material. Moreover, since the cast material which is solidified but is heated to some extent is subjected to rolling, it is excellent in workability. Therefore, the continuous cast rolled material can be produced with high productivity. In addition, for continuous cast rolled materials, due to the lack of lubricant on the surface of the rolling roll, oxides attached to the surface of the rolling roll, exfoliation pieces due to damage to the rolling roll, etc., reattach to the material. Defects due to device abnormalities may occur. However, by passing through the above-mentioned specific skinning process, a copper material for wire rods having excellent surface properties can be produced even when a continuously cast rolled material is used as the rod-shaped material. Therefore, the said form can manufacture the copper raw material for wire materials which is excellent in surface property further with high productivity.

  As one form of the manufacturing method of the copper raw material for wire rods of the present invention, the skinning step includes a form satisfying at least two of the above (A) to (C). Moreover, the form which satisfy | fills all said (A)-(C) is mentioned as said skinning process as one form of the manufacturing method of the copper raw material for wire rods of this invention.

  The said form is easy to further reduce the surface defect of the copper raw material for wires, and the copper raw material for wires excellent in surface property is obtained. By using this copper material for wire rods, disconnection can be further reduced in the production of copper base wire rods, and it can contribute to the improvement of productivity of copper base wire rods that are further excellent in surface properties.

  As an embodiment of the method for producing a copper material for a wire according to the present invention and a copper material for the wire according to the present invention, the copper base wire may be used for a conductor of a covered electric wire having an insulation coating.

  Since the copper base wire obtained by subjecting the copper material for wire obtained by the method for producing a copper material for wire according to the present invention to wire drawing (main processing) is excellent in surface properties as described above, the copper base When a wire is used as a conductor of a covered electric wire, the adhesion between the copper base wire and the insulation coating is excellent. Therefore, the said form can contribute to the improvement of the productivity of the conductor wire of a covered electric wire.

  The copper material for wire of the present invention is subjected to wire drawing (main processing) as described above to become a copper base wire. As a method for producing this copper base wire, for example, it comprises a wire drawing step for producing a copper base wire by subjecting the copper material for wire to a wire drawing process following the skinning process. The method for producing a copper base wire of the present invention which is continuously performed without winding up the material can be used.

  In the above configuration, since the intermediate wire that has not reached the final wire diameter is not wound, a new surface flaw is generated in the wire or due to winding, strain is introduced into the wire. Thus, a copper base wire material having excellent surface properties can be obtained. Moreover, since the number of processes can be reduced by deleting the winding process, the above-described embodiment can improve the productivity of the copper base wire. Furthermore, when the wound intermediate wire is rewound and the next pass is drawn, the center axis of the wire may be displaced, etc., but the above-described form has straightness up to the final wire diameter after stripping. It is possible to manufacture a copper base wire material that is maintained and hardly misaligns the material, and has excellent dimensional accuracy and shape accuracy.

  The method for producing a copper material for a wire of the present invention and the copper material for a wire of the present invention can contribute to an improvement in the productivity of a copper base wire having excellent surface properties. The copper base wire of the present invention is excellent in surface properties. The method for producing the copper base wire of the present invention can produce the copper base wire of the present invention with high productivity.

In the manufacturing method of the copper raw material for wire rods of this invention, it is explanatory drawing explaining a skinning process.

Hereinafter, the present invention will be described in more detail.
<Method for producing copper material for wire>
<Preparation process>
In the preparation step, a bar-shaped material made of copper or a copper alloy and subjected to at least casting is manufactured as a starting material. An example of the rod-shaped material is a cast material. In particular, when a continuous cast material is used, the productivity of the copper material for the wire can be improved. When the rod-shaped material is a continuously cast and rolled material, the productivity of the copper material for wire can be further improved.

  Copper is so-called pure copper containing 99.9% by mass or more of Cu and containing elements other than Cu (including impurities) in a total range of 0.1% by mass or less. Specifically, for example, oxygen-free copper (alloy number: C1020), tough pitch copper (alloy number: C1100), phosphorous deoxidized copper (alloy number: C1201, C1220), etc. stipulated in JIS H 3100 (2006) Can be mentioned. When the elements other than Cu are 0.1% by mass or less in total, a wire having high conductivity and toughness can be obtained, and can be suitably used for a conductor wire.

  Examples of elements other than Cu in pure copper include at least one metal element of Sn, Pb, Fe, Ag, Ni, and Zn. When the total content of these elements is more than 0 ppm and 100 ppm or less (0.01 mass% or less), it is easy to obtain a high-strength wire.

  Examples of the element other than the metal element include oxygen. When oxygen is contained in a mass ratio exceeding 0 ppm to 650 ppm or less (0.065 mass% or less), preferably about 200 ppm to 400 ppm, the conductivity can be increased by precipitating the impurity element as an oxide, and the coarsening of the oxide is suppressed. Thus, the remaining amount of oxide in the skinning material or wire drawing material can be reduced. Coarse oxides can be the starting point of disconnection at the time of skinning or wire drawing, leading to a decrease in productivity of the copper base wire. When the oxygen content is low, for example, at an oxygen-free copper level (about 10 ppm by mass ratio), a wire having excellent hydrogen embrittlement resistance can be obtained.

  The copper alloy contains, for example, at least one element of Sn, Ni, Si, Fe, P, Ag, and Cr as additive elements, and the balance is made of Cu and impurities, more specifically, Cu. -Sn alloy, Cu-Ni-Si alloy, Cu-Fe-P alloy, Cu-Ag alloy, Cu-Cr alloy and the like. A Cu-Sn alloy (preferably Sn content: 0.2% by mass or more and 6% by mass or less) can provide a high-strength wire. A Cu-Ag alloy (preferably Ag content: 0.1% by mass or more and 20% by mass or less) provides a wire having high shear strength and fatigue strength and high resistance to bending and twisting. A known copper alloy can be used.

  A raw material is prepared so as to have a desired composition, and a molten metal prepared by melting the raw material in an appropriate atmosphere is cast to manufacture a rod-shaped material. When the rod-shaped material is a continuous casting material, the molten metal is continuously cast. When the rod-shaped material is a continuous casting rolled material, the molten metal is continuously cast and subsequently rolled. Examples of the continuous casting include a twin belt method, a belt-and-wheel method, a horizontal drawing method, and a top casting method. By providing a continuous casting machine and a rolling mill, rolling can be performed continuously with continuous casting, and a continuously cast rolled material can be produced. Known conditions can be used for die casting, continuous casting, and rolling.

<Copper material for wire>
A rod-shaped material such as a continuously cast rolled material typically has a circular or rectangular cross-sectional shape, and the cross-sectional shape is not particularly limited. The wire diameter of a rod-shaped material such as continuous cast rolled material can be selected according to the application (final wire diameter) of the copper base wire, for example, the material of the copper base wire material having a relatively large final wire diameter such as a trolley wire. In the case of using for a copper base wire material such as a conductor for electric wires, about 8 mm to 10 mm is mentioned.

  The continuous cast material has a smaller average crystal grain size than the mold cast material (continuous cast material: about several hundred μm), and the continuous cast rolled material has a smaller average crystal grain size than the continuous cast material. Tens of μm or less, for example, 20 μm or less. Consisting of such a fine structure, the continuous cast rolled material has fewer coarse crystal grains that are the starting point of defects compared to the continuous cast material that has not been rolled. When applied, the surface layer region is partially stripped, so that the surface defects are easily removed uniformly in the circumferential direction. Therefore, it is easy to manufacture a copper material for wire rods having excellent surface properties by using a rod-shaped material as a continuously cast and rolled material.

<Peeling process>
Wire-drawing processing until a desired final wire diameter is applied to a rod-shaped material such as the above-mentioned continuous cast rolled material: skinning is performed before performing this processing. For the skinning process, a skinning die 100 having a die hole 110 through which the rod-like material 10 is inserted as shown in FIG. 1 can be suitably used.

  As a result of examination by the present inventors, when the removal amount for removing the surface layer region of a rod-shaped material such as a continuously cast rolled material by skinning is within a specific range, the obtained skin material is subjected to wire drawing (main processing). It was found that a copper base wire material that is difficult to break when applied and has excellent surface properties can be obtained. Therefore, it is proposed that the removal amount of the skinning is within a specific range. Specifically, the cross-sectional area of the rod-shaped material before skinning is Sa, the cross-sectional area of the material after skinning (skinning material) is Sb, and the cross-sectional area ratio is {(Sa-Sb) / Sa} × 100 When the cross-sectional area ratio is 1% or more and 10% or less. If the removal amount is too large, especially if it exceeds 10%, it is difficult to remove the surface layer region uniformly in the circumferential direction of the rod-shaped material, and the blade edge may bite deeply locally, which may cause flaking. Due to this mochi-mochi, there is a possibility that disconnection may occur at the time of skinning or at the time of main processing after skinning. On the other hand, if the removal amount is too small, especially less than 1%, surface defects remain in the stripping material, and these remaining defects may cause disconnection during the main processing or decrease in the surface properties of the copper base material after the main processing. Incurs deterioration of dimensions and shape. The removal amount can be selected within the above range depending on the composition, the wire diameter of the rod-shaped material before skinning, the use of the copper base wire, and the like.

  As a result of the study by the present inventors, when the rake angle of the cutting edge of the skinning die is in a specific range, it is difficult to break when the obtained skinning material is drawn (main processing), and the surface properties The copper base wire material which is excellent in the quality was obtained. Therefore, it is proposed to set the rake angle of the cutting edge of the peeling die within a specific range. Specifically, the rake angle is set to 2 ° to 50 °. As shown in FIG. 1, the rake angle is a surface (disposed on one end side of the die 100) that becomes the cutting edge 120 of the die 100 when a perpendicular line Lo perpendicular to the central axis La of the die hole 110 of the peeling die 100 is taken. The angle formed by the surface Lo) and the perpendicular Lo. If the rake angle θ is too small, especially less than 2 °, the resistance force applied to the die 100 when peeling is increased, the load on the cutting edge 120 of the cutting blade 120 is excessively loaded, and the die 100 is cracked or chipped. There is a possibility that the rod-shaped material 10 (continuous cast rolled material, pre-processed material, etc.) breaks during peeling. If the rake angle θ is too large, especially if it exceeds 50 °, the cutting edge 121 will bite into the rod-shaped material 10 and the rod-shaped material 10 will break when peeling off, or a mottle will be generated, and this processing will be performed with the mower There is a possibility that disconnection sometimes occurs or a copper base wire material having poor surface properties is obtained. The rake angle θ can also be selected within the above range depending on the composition, the wire diameter of the rod-shaped material, the use of the copper base wire, and the like. In particular, when the rod-shaped material is a continuously cast and rolled material, the smaller the rake angle θ, the easier it is to obtain a copper base material having excellent surface properties, and the angle can be set to 25 ° or less and further less than 20 °. Moreover, although it depends on the composition, when the rake angle θ is less than 15 ° in the case of a copper alloy, it is easy to obtain a copper base wire having excellent surface properties.

  As a result of the study by the present inventors, it was obtained after a wire drawing process (hereinafter referred to as pre-processing) was performed at a specific wire drawing degree before the bar-shaped material such as a continuous cast rolled material was subjected to skinning. When stripping the pre-processed material, it is easy to align the center axis of the pre-processed material and the center axis of the hole of the stripping die (centering can be performed with high precision), and the material (here, pre-processed material) Acquired knowledge that the surface layer region can be uniformly removed in the circumferential direction, and that when the obtained skinning material is subjected to main processing, it is difficult to break, and a copper base wire material having excellent surface properties can be obtained. It was. Therefore, it is proposed to perform pre-processing in the skinning process. Specifically, in pre-processing, the degree of wire drawing is 15% or more and 75% or less. If the degree of pre-drawing is too small, especially if it is less than 15%, it is difficult to align the above-mentioned center axis with high accuracy, and the material (pre-processed material here) will be peeled off when the center axis is displaced. If the material (here, pre-processed material) is unevenly distributed in the hole of the peeling die, the surface area of the material (here, pre-processed material) will be unevenly removed. , Surface defects may remain. The higher the pre-drawing wire drawing, the easier it is to increase the alignment accuracy of the central axis. However, when the pre-drawing wire drawing degree is too high, especially when it exceeds 75%, the work hardening of the pre-worked material becomes large and the softness is lowered. When peeling, the resistance to the peeling dies increases, and there is a risk that the dies will crack, break when peeling, or new wrinkles will occur on the peeling material and breakage may occur during the main processing starting from the wrinkles. is there. The drawing degree of pre-processing can also be selected within the above range depending on the composition, the wire diameter of the rod-shaped material, the use of the copper base wire, and the like.

  In addition, as a pre-treatment before skinning, if the surface of the material (continuously cast rolled material, pre-processed material, etc.) is cut in a spiral shape, it is easy to remove chips generated by skinning, Can prevent adhesion.

  By performing at least one of the removal amount control, the rake angle control, and the pre-processing, a copper base wire material having excellent surface properties can be obtained. When at least two of the removal amount control, rake angle control, and pre-processing are performed, disconnection during wire drawing (main processing) is further reduced, and a copper base wire material having excellent surface properties is manufactured with high productivity. it can. In particular, if all of the above removal amount control, rake angle control, and pre-processing are performed, disconnection during wire drawing (main processing) can be effectively reduced, and a copper base wire with excellent surface properties can be made more productive. Can be manufactured well.

<Method for producing copper base wire>
A copper base wire is obtained by subjecting the copper material for wire of the present invention to wire drawing (main processing) to a desired final wire diameter. Various wire diameters, mechanical properties (tensile strength, elongation, etc.), electrical conductivity, by appropriately adjusting the drawing conditions (drawing degree per pass, total workability, intermediate heat treatment, die shape, etc.) It is possible to obtain a copper base wire having a rate and shape. The wire drawing (main processing) is typically performed by cold working.

  In particular, when the wire drawing process (main process) is performed subsequent to the skinning process, a wire drawing material having high straightness and excellent dimensional accuracy and shape accuracy can be produced. Further, in this embodiment, it is not necessary to rewind the material once wound up and align the center axis of the material with the center axis of the wire drawing die, thereby omitting the winding / rewinding process and the center axis alignment process. The productivity of copper base wire can be further increased.

  Furthermore, when wire drawing (main processing) is performed over multiple passes, the wire is continuously wound up to the final wire diameter without winding up the material. A process and a center axis alignment process are unnecessary, and the productivity of the copper base wire can be further increased. Moreover, since this form can prevent that a new wrinkle etc. are formed at the time of winding-up / rewinding, the copper base wire material which is further excellent in surface property can be manufactured. Furthermore, by preventing the generation of new wrinkles, it is possible to prevent disconnection starting from the wrinkles at the time of wire drawing. From this point as well, this configuration can contribute to the improvement of productivity.

  When performing multi-pass wire drawing, if an intermediate heat treatment is appropriately performed in the middle of wire drawing (between passes), distortion before the heat treatment can be reduced or removed, and the grain size can be refined. Can improve the workability. As described above, in the form in which winding is not performed in the middle of wire drawing, the intermediate heat treatment is performed continuously using a heating means capable of continuous heating, such as a pipe softening furnace, a high-frequency heating furnace, an electric heating furnace, etc. It is good to treat. After wire drawing (main processing), heat treatment can be performed for the purpose of removing strain or refining crystals. This heat treatment may be a batch process in which the material is heated in a state of being stored in a heating device.

<Copper base wire>
The copper base wire material has been subjected to wire drawing (main processing), and has high strength due to work hardening. Depending on the composition, etc., the conductivity is 90% IACS or higher, and further 95% IACS or higher. It can also be a wire. By appropriately performing a softening treatment (intermediate heat treatment) in the middle of wire drawing (between passes), it is possible to improve the toughness such as elongation and the conductivity by precipitation of precipitates.

  A copper base wire is typically a round wire having a circular cross-sectional shape. Depending on the shape of the wire drawing die, etc., various cross-sectional shapes of wire can be obtained. Moreover, it can be set as the wire of various cross-sectional shapes also by giving the process etc. which change cross-sectional shape, such as a flat angle process and a grooving process, after wire drawing.

  The wire diameter of the copper base wire (in the case of a deformed wire, the diameter of the envelope circle) can be adjusted depending on the degree of wire drawing (main processing), and may be appropriately selected according to the application. For example, when used as a conductor for electric wires, the wire diameter may be a fine wire having a diameter of 1 mm or less, or an extra fine wire having a diameter of 0.1 mm or less, and further 0.010 mm or more and 0.05 mm or less. Of course, a wire having a wire diameter exceeding 1 mm, for example, a wire having a wire diameter of about 2 mm to 5 mm, or a wire having a diameter of 10 mm or more can also be used.

  The copper base wire of the present invention can be used as a single wire, a stranded wire obtained by twisting a plurality of wires, or a compressed wire obtained by compressing a stranded wire. Single wires, stranded wires, and compressed wires can all be used as they are (bare wires), or can be used as a covered wire by providing, for example, an insulating coating on the outer periphery thereof.

<Test example>
Hereinafter, specific examples of the present invention will be described with reference to test examples.
In this test, multiple types of raw materials are prepared, a continuous cast rolled material is produced as a rod-shaped material, and the continuous cast rolled material is stripped under various conditions, and then subjected to wire drawing to obtain a copper base. A wire was prepared, and the surface state of each obtained copper base wire was examined.

  As raw materials, pure copper (Cu: 99.9 mass% or more), low concentration alloy (Sn content: 0.3 mass% Cu-Sn alloy), high concentration alloy (Ag content: 5.0 mass% Cu-Ag alloy) Was prepared to prepare a molten metal. The produced molten metal is continuously cast using a continuous casting method of any one of the double belt method, belt-and-wheel method, lateral drawing method, and top casting method, and the ingot produced following this continuous casting. A continuous cast rolled material made of pure copper, a low concentration alloy, or a high concentration alloy was produced.

  The produced continuous cast rolled material was stripped under the conditions shown in Table 1. Specifically, after performing the wire drawing (pre-processing) of the wire drawing degree shown in Table 1 on the continuous cast rolled material, using a peeling die whose rake angle of the cutting edge is the value shown in Table 1, Skinning was performed so that the removal amount shown in Table 1 (cross-sectional area ratio (%): {(Sa-Sb) / Sa} × 100) was obtained. And the presence or absence of the disconnection at the time of skinning was investigated. The results are shown in Table 1. The sample No. 100 is not pre-processed or skinned.

  Each stripping material obtained by skinning was subjected to wire drawing (main processing) subsequent to skinning. In this test, the wire was drawn until the wire diameter became φ2.6 mm without winding the material in the middle. The surface of each obtained wire drawing material was examined with a commercially available eddy current flaw detector and the surface condition was evaluated. In this test, the continuous cast and rolled material of sample No. 100 was drawn to a wire diameter of 2.6 mm, and the surface of the obtained wire was examined with the eddy current flaw detector, and per 1 ton (1000 kg) of the drawn wire. The average number of samples was set to a reference value of 1, and the surface state of each sample peeled was evaluated by a relative value with respect to this reference value. The results are shown in Table 1.

  About each sample which peeled, the wire drawing process (main process) was performed until it became wire diameter (phi) 2.6mm, and the presence or absence of the disconnection at the time of the said wire drawing was investigated. The results are shown in Table 1.

  As shown in Table 1, after stripping a bar-shaped material such as a continuous cast rolled material, by performing wire drawing (main processing), it tends to reduce the surface defects of the copper base wire obtained after wire drawing I understand that there is. In particular, by stripping at least one of the removal amount, rake angle, and pre-drawing wire drawing degree within a specific range, it is difficult to break during this processing (here, substantially no wire breakage). It can be seen that the surface defects of the copper base wire obtained after the wire can be sufficiently reduced. Specifically, the average count of flaw detection is 0.80 or less with respect to the reference value of sample No. 100 where skinning was not performed. Also, when stripping at a specific range of at least two of removal amount, rake angle, and predrawing wire drawing degree, a copper base material with fewer surface defects can be obtained (0.50 or less relative to the reference value). ), And skinning with all three in a specific range, it can be seen that the surface defects can be further reduced (0.40 or less with respect to the reference value), and a copper base material having excellent surface properties can be obtained.

  In addition, as shown in Table 1, when the rake angle of the cutting edge is less than 20 ° (here, 3 ° or more and 18 ° or less) for both pure copper and copper alloy, the surface defects of the copper base material are reduced. It turns out that it is easy.

  Sample No. 110, which was skinned but the condition was outside the specified range, was disconnected during the skinning process or wire drawing process, so flaw detection was not possible, and sample No. 120 was disconnected during the skinning process. Although not, it can be seen that the effect of reducing surface defects is small.

  From the above, before performing wire drawing (main processing) to a rod-shaped material such as continuously cast rolled material until the desired final wire diameter is applied, stripping is performed under specific conditions, thereby breaking the wire during the main processing. It can be seen that a copper base wire having excellent surface properties can be produced with high productivity. The obtained copper base wire has excellent surface properties, and when used as a conductor wire, it has excellent strength, fatigue properties, bending properties and twisting properties, and is difficult to break during use. In this case, it is expected that the adhesion of the insulating coating is excellent.

  Note that 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. For example, the composition of the copper alloy, the final wire diameter, and the like can be changed as appropriate.

  The copper base wire material of the present invention is a conductor of various electric wires (for example, a conductor of a winding such as an enamel wire, a central conductor or a shield conductor of a coaxial cable, a stranded conductor, etc.), an electrode wire used for electric discharge machining, a welding material, etc. It can be suitably used for various conductor components such as welding wires and trolley wires used in the above. The copper material for wire of the present invention can be suitably used for the material of the copper base wire. The manufacturing method of the copper material for wire of the present invention and the method of manufacturing the copper wire of the present invention can be suitably used for manufacturing the copper material for wire of the present invention and for manufacturing the copper base material of the present invention.

  10 Bar material 100 Peeling die 110 Die hole 120 Cutting blade 121 Cutting edge

Claims (8)

A method for producing a copper material for a wire, which produces a copper material for a wire used as a material for a copper base wire that has been subjected to wire drawing,
A preparation step of manufacturing a bar-shaped material made of copper or a copper alloy and at least cast;
A skinning process for skinning the rod-shaped material,
The skinning step satisfies at least one of the following (A) to (C).
(A) The removal amount by the skinning process is 1% or more and 10% or less in terms of a cross-sectional area ratio.
(B) The skinning process is performed on a pre-processed material obtained by subjecting the rod-shaped material to a wire drawing of 15% or more and 75% or less in the degree of wire drawing.
(C) The rake angle of the cutting edge of the skinning die used for the skinning process is 2 ° or more and 50 ° or less.   2. The method for producing a copper material for wire according to claim 1, wherein the rod-shaped material is a continuously cast rolled material.   3. The method for producing a copper material for wire according to claim 1, wherein the skinning step satisfies at least two of (A) to (C).   3. The method for producing a copper material for wire according to claim 1, wherein the skinning step satisfies all of the above (A) to (C).   5. The method for producing a copper material for a wire according to claim 1, wherein the copper base wire is used as a conductor of a covered electric wire having an insulation coating.   A copper material for a wire obtained by the production method according to any one of claims 1 to 5. The copper material for wire according to claim 6, comprising a wire drawing step of producing a copper base wire material by performing wire drawing processing subsequent to the stripping processing,
The said wire drawing process is continuously performed, without winding up a raw material on the way, The manufacturing method of the copper base wire characterized by the above-mentioned.   A copper base wire obtained by the production method according to claim 7.

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