JP4240768B2 - Oxygen-free copper wire manufacturing method, manufacturing apparatus, and oxygen-free copper wire - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a production method, a production apparatus, and a produced oxygen-free copper wire for continuously producing an oxygen-free copper wire using a belt caster type continuous casting machine.
[0002]
[Prior art]
As a method for producing a copper wire, particularly an oxygen-free copper wire in which the oxygen content is suppressed to 10 ppm or less, usually 3 to 10 ppm, a so-called extrusion method, a dip forming method, or the like is known. The former extruding method is a method of extruding a copper billet or cake once into a rod shape and then forging or rolling it into an oxygen-free copper wire. Moreover, the latter dip forming method is a method in which a copper seed wire is passed through a molten metal tank, a molten metal is attached to the outer periphery of the seed wire to obtain a rod-shaped copper material, and this is rolled to make an oxygen-free copper wire. It is.
[0003]
In the case of the extrusion method, an expensive extrusion process is generally required, and further, forging or rolling is performed, resulting in an increase in manufacturing cost. Moreover, since the rod-shaped copper material obtained by the extrusion method can be obtained only in a finite length due to its production method, there is also a drawback that it is difficult to continuously obtain a long rod-shaped copper material.
In the case of the dip forming method, there is an advantage that oxygen-free copper wire can be continuously manufactured from molten copper in a series of production lines. However, it is not suitable for mass production and is not productive, and the entire manufacturing system is systematically used. In other words, it has to be controlled and managed, and therefore expensive equipment is required.
[0004]
As an alternative to such a conventional manufacturing method, for example, a manufacturing method using a belt caster type continuous casting machine disclosed in Japanese Patent Publication No. 59-6736 and Japanese Patent Application Laid-Open No. 55-126353 has been proposed. The main part of the belt caster type continuous casting machine used in this manufacturing method is composed of an endless belt that moves around and a casting wheel that rotates while contacting a part of the circumference with the endless belt. Then, it is connected to a large melting furnace such as a shaft furnace, and further connected to a rolling mill to continuously cast and roll the molten copper from the melting furnace to produce an oxygen-free copper wire at a high speed on a series of production lines. be able to. Therefore, high productivity can be obtained and mass production becomes possible, so that the manufacturing cost of the oxygen-free copper wire can be reduced. In this manufacturing method, a reduction process using a reducing gas and / or an inert gas is performed in the process of transferring molten copper to obtain a molten copper having a very low oxygen concentration, which is used as a cast copper material by a belt caster type continuous casting machine. The cast copper material is rolled to produce an oxygen-free copper wire.
[0005]
[Problems to be solved by the invention]
However, in such a belt caster type continuous casting machine, when the molten copper transported in a hermetic state is kept airtight and deoxidized by actually sealing with a reducing gas and / or inert gas, the molten copper is actually cast into the cast copper material. There was a problem that holes were generated and scratches were generated on the surface of the oxygen-free copper wire when the cast copper material was rolled, resulting in deterioration of the surface quality. When an oxygen-free copper wire with poor surface quality is used in, for example, a commutator provided inside a motor, the conductivity decreases due to scratches on the surface. Therefore, an oxygen-free copper wire with few scratches is required. ing. For these reasons, almost no oxygen-free copper wire manufactured using a belt caster type continuous casting machine is on the market, and oxygen-free copper wire is mainly manufactured by the dip forming method described above. Currently.
[0006]
Since the solubility of hydrogen (H) and oxygen (O) in the molten copper decreases when the molten copper solidifies, the holes are formed by combining water vapor (H₂O).
That is, water vapor bubbles are generated in the molten copper, and if these bubbles are trapped by cooling and solidification of the molten copper before it escapes from the molten metal surface to the atmosphere gas, holes are formed in the cast copper material. Is done. If the diameter of the hole is large, it becomes a harmful hole that appears as many scratches on the surface of the oxygen-free copper wire after rolling. In particular, in a belt caster type continuous casting machine, the cooling rate is very high and bubbles are easily trapped before they escape from the molten copper, so that such harmful holes are easily generated.
[0007]
Here, the concentration of hydrogen and oxygen in the molten copper is thermodynamically represented by the following equation.
[H]²[O] = p_H2O・ K ......... Formula (A)
In addition,
[H]: Hydrogen concentration in molten copper
[O]: Oxygen concentration in molten copper
p_H2O    : Partial pressure of water vapor in atmosphere
K: Equilibrium constant
It is.
Since the equilibrium constant K is a function of temperature and becomes a constant at a constant temperature, the oxygen concentration and the hydrogen concentration in the molten copper have an inversely proportional relationship. Therefore, the hydrogen concentration becomes higher as the reduction process, that is, the deoxygenation process is performed. That is, when an oxygen-free copper wire is produced under normal pressure, if not only deoxygenation treatment but also dehydrogenation treatment is performed, a large amount of harmful holes are generated at the time of solidification, resulting in good surface quality, that is, high It is not possible to produce quality oxygen-free copper wire.
[0008]
For these reasons, a method for suppressing the generation of harmful holes by sufficiently performing not only deoxygenation but also dehydrogenation has been studied. In this process, bubbling with an inert gas and stirring of the molten copper are performed in the molten copper transport process.
At a temperature of about 1083 ° C., which is a general temperature of molten copper, from the equilibrium with water vapor and hydrogen, for example, when the oxygen concentration is 10 ppm, the hydrogen concentration is 0.2 ppm or less, and when the oxygen concentration is 1 ppm, the hydrogen concentration is reduced. If not less than 0.4 ppm, bubbles are generated. That is, holes are generated in the cast copper material. Such a dehydrogenation device for reducing the hydrogen concentration is generally a large-scale and complicated device, which makes it difficult to secure an installation location or a dehydrogenation processing time. Moreover, it is difficult to always maintain such manufacturing conditions.
[0009]
If the water vapor partial pressure of the generated bubbles can be kept low, the bubble diameter can be reduced, and the generation of harmful holes can be suppressed. That is, if molten copper can be cast under high pressure, an oxygen-free copper wire with good surface quality can be produced. However, the entire belt caster type continuous casting machine must be in a high pressure condition, and the apparatus for that purpose becomes very large and complicated, and it is very difficult to actually carry out.
[0010]
Moreover, the method of adding phosphorus (P) in molten copper is known. Phosphorus has a high binding force to oxygen, and has the effect of reducing the chemical potential of oxygen by binding to oxygen, making it difficult for oxygen and hydrogen to bond during solidification, that is, making it difficult for holes to be generated. However, when phosphorus is added, there is a problem that the conductivity of the oxygen-free copper wire is lowered, which is not a preferable method.
[0011]
As a result of intensive studies, the inventors of the present invention added a small amount of silver (Ag) to finely disperse the holes formed in the cast copper material, so that the microholes disappear so as not to be damaged during rolling. It was possible to suppress the generation of harmful holes.
[0012]
The present invention has been made in view of the above situation, and an oxygen-free copper wire that suppresses a decrease in electrical conductivity and has good surface quality, and such an oxygen-free copper wire can be manufactured at low cost using a belt caster type continuous casting machine. An object of the present invention is to provide a manufacturing method and a manufacturing apparatus capable of mass production.
[0013]
[Means for Solving the Problems]
  According to the first aspect of the present invention, molten copper is supplied to a belt caster continuous casting machine, and the cast copper material derived from the belt caster continuous casting machine is rolled to continuously produce an oxygen-free copper wire. And a molten copper production process for producing molten copper by burning in a reducing atmosphere of a melting furnace, and a cast iron capable of sealing the molten copper sent from the melting furnace in a non-oxidizing atmosphere. Molten copper transporting process for transporting to the tundish, a degassing process for dehydrogenating by stirring the molten copper passing through the cast iron, and an oxygen content of 3-10 ppm in the degassing process. A silver addition step of adding silver to the molten copper having a content of 1 ppm or less so that the silver content is 0.005 to 0.2 wt%, and a belt caster type continuous copper to which the silver is added Continuous casting by feeding to casting machine And forming step, and a rolling step of rolling the been cast copper material formed by the belt caster type continuous casting machineAnd the degassing step is stirred by causing the molten copper to meander up and down at least by means of an upper dam provided on the upper side of the flow path and a lower dam provided on the lower side.It is characterized by that.
[0014]
  In this method of producing an oxygen-free copper wire, combustion is performed in a reducing atmosphere in a melting furnace, the molten copper is deoxidized, and the molten copper is sealed in a non-oxidizing atmosphere in a cast iron and transferred to a tundish. The This molten copper has a high hydrogen concentration because the oxygen concentration and the hydrogen concentration are inversely proportional, but is dehydrogenated in the subsequent degassing step. As a result, the hydrogen concentration, which becomes higher as the deoxygenation is performed by reduction, becomes lower, and the generation of holes during solidification is suppressed. Then, silver can be further added to the molten copper in which holes are hardly generated by the deoxygenation treatment and the dehydrogenation treatment to finely disperse the holes, thereby forming microholes. Therefore, it is possible to obtain a cast copper material that is harmful, that is, suppresses the generation of holes that become scratches after rolling, and an oxygen-free copper wire with good surface quality that significantly reduces surface scratches can be obtained. .
  Further, by stirring the molten copper, hydrogen in the molten copper is forcibly expelled, and dehydrogenation treatment can be performed. That is, the molten copper before being transferred to the tundish is stirred, and the contact property between the molten gas blown to form a non-oxidizing atmosphere and the molten copper is improved. At this time, since the hydrogen partial pressure in the inert gas is extremely small with respect to the hydrogen partial pressure of the molten copper, the hydrogen in the molten copper is taken into the inert gas and the molten copper can be dehydrogenated.
  further,The molten copper that passes through the casting gutter is caused to flow in a meandering manner, and is agitated by vigorous flow. That is, since it can be automatically stirred by the flow of the molten copper itself, the molten copper flowing through the cast iron has an opportunity to uniformly contact the inert gas, and the efficiency of the dehydrogenation treatment is further enhanced.
  In this case, for example, a rod-like or plate-like weir provided in the molten copper flow path is suitable. Further, a plurality of weirs may be provided in the direction of molten copper flow, or a plurality of weirs may be provided in a direction orthogonal to the flow of molten copper. Furthermore, if this weir is made of, for example, carbon, deoxidation treatment can be efficiently performed by contact between the molten copper and carbon.
[0015]
  Invention of Claim 2 is a manufacturing method of the oxygen-free-copper wire of Claim 1, Comprising: In the said degassing process,By the upper weir provided above the flow pathIt is characterized in that mixing of the atmospheric gas before and after the dehydrogenation treatment is prevented.
[0019]
  Claim 3The invention described in 1 is a manufacturing apparatus that continuously supplies oxygen-free copper wire by supplying molten copper to a belt caster continuous casting machine, rolling the cast copper material derived from the belt caster continuous casting machine A melting furnace for producing molten copper by burning in a reducing atmosphere, a holding furnace for holding the molten copper sent from the melting furnace at a predetermined temperature, and a molten copper sent from the holding furnace. A cast iron that is sealed in a non-oxidizing atmosphere and transferred to the tundish, and a molten copper that is provided in the cast iron and passes throughStirring by meandering at least up and down by an upper dam provided on the upper side of the flow path and a lower dam provided on the lower side,Degassing means for performing dehydrogenation treatment of the molten copper, and the molten copper in which the oxygen content is 3 to 10 ppm and the hydrogen content is 1 ppm or less by the degassing means, the silver content is 0.005 to 0.005. Silver addition means for adding silver so as to be 0.2 wt%, belt caster type continuous casting machine for continuously casting molten copper to which silver is added, and cast copper material formed by the belt caster type continuous casting machine A rolling mill for rolling
  Claim 4The invention described inClaim 3An apparatus for producing oxygen-free copper wire according to claim 1, wherein the cast iron is covered with an upper cover, and the upper cover extends downward and is mixed with atmospheric gas before and after the dehydrogenation treatment. An upper weir is provided to prevent this.
[0020]
  Since the oxygen-free copper wire manufacturing apparatus has such a configuration, the aboveClaims 1, 2The method for producing an oxygen-free copper wire described in 1 can be preferably carried out.
[0021]
  Claim 5The invention described inClaim 1 or 2Or by the method for producing an oxygen-free copper wire describedClaim 3 or 4An oxygen-free copper wire manufactured using the oxygen-free copper wire manufacturing apparatus described above, wherein 0.005 to 0.2 wt% of silver is contained.
  Also,Claim 6The invention described inClaim 5The oxygen-free copper wire according to claim 1, which contains 0.03 to 0.20 wt% of silver.
  Furthermore,Claim 7The invention described inClaim 6The oxygen-free copper wire as described in 1), characterized in that it contains 0.05 to 0.20 wt% of silver.
[0022]
As described above, when 0.005 wt% or more of silver is contained, holes can be finely dispersed to form fine microholes, and scratches on the surface of the oxygen-free copper wire obtained by rolling can be reduced.
And if it contains 0.03 wt% or more, a damage | wound can be reduced notably, and if it contains 0.05 wt% or more, a damage | wound can be reduced further notably.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of an oxygen-free copper wire, a method for manufacturing the same, and a manufacturing apparatus according to the present invention will be described in detail with reference to the drawings. In the following, the “oxygen-free copper wire” refers to a copper wire in which the oxygen content is suppressed to 10 ppm or less, usually 3 to 10 ppm.
First, an oxygen-free copper wire manufacturing apparatus will be described. FIG. 1 is a configuration diagram schematically showing an oxygen-free copper wire manufacturing apparatus according to the present embodiment, and FIG. 2 is a cross-sectional view of the cast iron shown in FIG. 1 in plan view (a) and side view (b). It is.
[0024]
The oxygen-free copper wire manufacturing apparatus 1 includes a melting furnace A, a holding furnace B, a casting rod C, a belt caster continuous casting machine D, a rolling mill E, and a coiler F. .
[0025]
As the melting furnace A, for example, a shaft furnace having a cylindrical furnace body is suitably used. In the lower part of the melting furnace A, a plurality of burners (not shown) in the circumferential direction are provided in multiple stages in the vertical direction. In the melting furnace A, combustion is performed in a reducing atmosphere, and deoxidized molten copper (hot water) is produced. The reducing atmosphere can be obtained, for example, by increasing the fuel ratio in a mixed gas of natural gas and air.
[0026]
The holding furnace B is for temporarily storing the hot water sent from the melting furnace A and sending it to the casting iron C while keeping it at a predetermined temperature.
The cast iron C is sealed in the non-oxidizing atmosphere with hot water sent from the holding furnace B and transferred to the tundish 5. As shown in FIG. 2, the sealing is performed by covering the upper surface of the molten copper flow path (molten copper flow path) 31 of the cast iron C with a cover 8. This non-oxidizing atmosphere is formed, for example, by blowing a mixed gas of nitrogen and carbon monoxide or a rare gas such as argon into the casting rod C as an inert gas.
[0027]
As shown in FIG. 2, the molten copper flow path 31 in the cast iron C is provided with a stirring means (degassing means) 33 as a degassing means including a dehydrogenation process. The stirring means 33 is composed of weirs 33a, 33b, 33c, and 33d, and the hot water flows while being vigorously stirred.
[0028]
The weir 33 a is provided on the upper side of the molten copper flow path 31, that is, on the cover 8. The weir 33 b is provided below the molten copper flow path 31, the weir 33 c is provided on the left side of the molten copper flow path 31, and the weir 33 d is provided on the right side of the molten copper flow path 31. By these weirs 33a, 33b, 33c, and 33d, hot water is stirred in the direction of the arrow in FIG. In addition, in FIG.2 (b), the hot_water | molten_metal surface is shown as the code | symbol 32. FIG.
The weirs 33c and 33d can increase the efficiency of the degassing treatment even if the length of the hot water flow channel is made longer than the actual length of the molten copper flow channel 31 and the cast iron C is short. It is. The weirs 33a and 33b serve to prevent mixing of the molten copper and the atmospheric gas before and after the degassing process.
The stirring means 33 is mainly for performing a dehydrogenation process, but oxygen remaining in the hot water can also be driven out by stirring the hot water. That is, both the dehydrogenation process and the second deoxygenation process are performed as the degassing process. If these weirs 33a, 33b, 33c, and 33d are made of, for example, carbon, deoxidation treatment can be efficiently performed by contact between the molten copper and carbon.
[0029]
This degassing process needs to be performed in the transfer process after the holding furnace B. The reason is that the holding furnace B performs combustion in a reducing atmosphere or deoxidation with a reducing agent in order to obtain a low-oxygen copper wire, so that the hydrogen concentration inevitably increases due to the relationship of the above equilibrium equation (A). It is.
[0030]
Furthermore, as a position for performing the degassing process, the degassing process in the tundish 5 immediately before casting is not preferable. The reason is that when hot water is vigorously stirred in the tundish 5, for example, bubbling, the hot water surface vibrates violently, the head pressure of the hot water coming out of the pouring nozzle 9 fluctuates, and stable molten copper is produced. This is because it is not supplied to the casting machine D. On the other hand, the degassing effect cannot be expected as long as the molten metal surface does not vibrate vigorously. Also from this, it is preferable to perform the degassing process in the transfer process from the holding furnace B to the tundish 5.
[0031]
A silver addition means (not shown) is provided in the vicinity of the terminal portion of the cast iron C so that silver can be added to the deoxygenated and dehydrogenated hot water.
In addition, the place where this silver addition means is provided is not limited to the terminal part vicinity of the casting iron C. That is, it may be added to the hot water after the dehydrogenation treatment and sufficiently diffused, and may be provided between the end of the cast iron C and the end of the tundish 5.
[0032]
The tundish 5 is provided with a pouring nozzle 9 at the end of the hot water flow direction so that hot water from the tundish 5 is supplied to the belt caster type continuous casting machine D.
[0033]
A belt caster continuous casting machine D is connected to the holding furnace B via a casting rod C. The belt caster type continuous casting machine D includes an endless belt 11 that moves around and a casting wheel 13 that rotates while contacting a part of the circumference with the endless belt 11. The casting machine D is further connected to a rolling mill E.
[0034]
The rolling mill E rolls the cast copper material 23 output from the casting machine D. The rolling mill E is connected to the coiler F via the flaw detector 19.
[0035]
An oxygen-free copper wire manufacturing method using the oxygen-free copper wire manufacturing apparatus 1 configured as described above will be described.
First, combustion is performed in a reducing atmosphere in the melting furnace A, and molten copper is produced while deoxidizing the molten copper (molten copper production step). The deoxidized molten copper is sealed in a non-oxidizing atmosphere using the cast iron C and transferred to the tundish 5 (molten copper transfer step). The molten copper deoxidized in the melting furnace A has a high hydrogen concentration because the oxygen concentration and the hydrogen concentration are in an inversely proportional relationship. The molten copper having a high hydrogen concentration is dehydrogenated by the stirring means 33 (degassing step) when passing through the casting iron C.
[0036]
Thus, the molten copper is adjusted to have an oxygen content of 3 to 10 ppm and a hydrogen content of 1 ppm or less. Then, silver is added from the silver addition means to the molten copper whose oxygen concentration and hydrogen concentration are adjusted so that the silver content in the molten copper is 0.005 to 0.2 wt% (silver addition step). .
If the silver content is less than 0.005 wt%, it can hardly be expected to make holes finer, that is, to suppress surface scratches. On the other hand, if the silver content is more than 0.2 wt%, the strength of the oxygen-free copper wire will increase even if the effect of suppressing scratches does not change so much. This makes it difficult to perform post-processing and the like.
For these reasons, the silver content is preferably within the above range.
[0037]
Moreover, since the gas concentration of molten copper falls by lowering | hanging water vapor partial pressure from the relationship of equilibrium type | formula (A), the molten copper before performing a dehydrogenation process and the molten copper after a dehydrogenation process are isolate | separated completely. And a further degassing effect can be obtained. This can be realized, for example, by providing the stirring means 33 as described above in the molten copper transfer step. That is, the stirring means 33 also serves to prevent the mixing of the atmospheric gas before and after the dehydrogenation process and the mixing of the molten copper.
[0038]
As described above, the molten copper transferred from the melting furnace A to the holding furnace B is heated, and then supplied to the belt caster continuous casting machine D through the casting rod C and the tundish 5, and the belt caster continuous casting is performed. It is continuously cast in the casting machine D, and is formed into a cast copper material 23 when leaving the belt caster type continuous casting machine D. The cast copper material 23 is rolled by a rolling mill E, thereby forming an oxygen-free copper wire 25 containing a predetermined amount of silver and having good surface quality, and is wound around a coiler F.
[0039]
The separation by the stirring means 33 is not limited to one place, and may be appropriately installed according to the length of the transfer process. In addition, weirs 33a, 33b, 33c, and 33d are provided on the upper, lower, left, and right sides of the molten copper flow path 31 as the stirring means 33, but the number and arrangement of these weirs are appropriately changed depending on the length and width of the cast iron C. However, it does not matter.
[0040]
In this way, by adjusting the oxygen concentration and the hydrogen concentration and casting and rolling the molten copper after the addition of a predetermined amount of silver, gas emission during casting is reduced and produced in the cast copper material 23. Holes are suppressed, and scratches on the surface of the oxygen-free copper wire 25 are reduced.
[0041]
FIG. 3 shows a result of the flaw detection test on the surface of the oxygen-free copper wire 25 obtained by the manufacturing method using the manufacturing apparatus as described above. This flaw detection inspection was performed by a rotation phase type eddy current flaw detection method using a rotation phase type eddy current flaw detector for copper wire (manufacturer name: Nippon Estec, model name: RP-7000).
In FIG. 3, (a) does not contain silver, (b) contains 0.01 wt% silver, (c) contains 0.03 wt% silver, (d ) Shows charts when flaws containing 0.05 wt% are detected. In each figure, the vertical axis represents time, and the horizontal axis represents the voltage (V) of eddy current generated corresponding to the number and size of flaws.
[0042]
As shown in these figures, as the silver content in the oxygen-free copper wire 25 increases, that is, as the amount of silver added to the molten copper increases, scratches on the surface of the oxygen-free copper wire 25 decrease. I understand that.
This is because, if an element capable of refining copper crystal grains can be added to increase the grain boundary, the concentration of gas components per unit grain boundary decreases, and hydrogen, oxygen, and water vapor in the cast copper material 23 decrease. This is because the apparent gas component concentration is much lower than that in the case where the grain boundary is large, and as a result, it is estimated that large holes are hardly formed.
According to the study by the present inventors, silver is a suitable additive element, and if 0.005 wt% or more of silver is contained, the holes formed in the cast copper material 23 are finely dispersed. Thus, the surface of the oxygen-free copper wire 25 obtained by rolling the cast copper material 23 can be reduced. And if it contains 0.03 wt% or more, a damage | wound can be reduced notably, and if it contains 0.05 wt% or more, a damage | wound can be reduced further notably.
[0043]
In the oxygen-free copper wire manufacturing apparatus and the manufacturing method using the same according to the present embodiment, combustion is performed in a reducing atmosphere in the melting furnace A, the molten copper is deoxygenated, and the molten copper is cast. In C, it is sealed in a non-oxidizing atmosphere and transferred to tundish 5. The molten copper has a high hydrogen concentration because the oxygen concentration and the hydrogen concentration are inversely proportional to each other, but is dehydrogenated by the stirring means 33 in the subsequent degassing step. As a result, the hydrogen concentration, which becomes higher as the deoxygenation is performed by reduction, becomes lower, and the generation of holes during solidification is suppressed. Then, silver can be further finely dispersed by adding silver from the silver addition means to the molten copper in which holes are difficult to be generated by the deoxygenation treatment and the dehydrogenation treatment, thereby forming microholes.
Therefore, by using a belt caster type continuous casting machine, it is possible to continuously produce a long cast copper material that suppresses a decrease in conductivity and has few harmful holes at a low cost. Moreover, even if the degassing process is simplified, an oxygen-free copper wire with good surface quality in which surface scratches are significantly reduced can be obtained. As a result, it is not necessary to use an expensive and special device such as a device for performing a dehydrogenation process, such as a vacuum degassing device, a bubbling device, or an alloy furnace, the device configuration can be simplified, and the cost can be reduced. An oxygen copper wire can be manufactured.
[0044]
Further, since the degassing means is the stirring means 33 for stirring the molten copper, the dehydrogenation process can be performed forcibly in a short time, and therefore, the dehydrogenation process can be efficiently performed with a simple configuration.
[0045]
Further, if the stirring means 33 is constituted by a weir that meanders the flow path of the molten copper, the stirring means 33 is automatically stirred by the flow of the molten copper itself. With the configuration, dehydrogenation can be efficiently performed, and operation management of an oxygen-free copper wire manufacturing apparatus can be easily performed.
[0046]
In addition, since the oxygen-free copper wire 25 according to the present embodiment contains 0.005 to 0.2 wt% of silver, a decrease in conductivity is suppressed, and the surface quality is low with few scratches. It can be good, i.e. of high quality.
[0047]
【The invention's effect】
As described above in detail, in the method and apparatus for producing an oxygen-free copper wire according to the present invention, since silver is added to the molten copper, the surface is obtained using a belt caster type continuous casting machine. High quality oxygen-free copper wire with good quality can be mass-produced at low cost.
Moreover, by containing a certain amount of silver, it is possible to provide a high-quality oxygen-free copper wire in which a decrease in electrical conductivity is suppressed.
[Brief description of the drawings]
FIG. 1 is a configuration diagram schematically showing an oxygen-free copper wire manufacturing apparatus according to an embodiment of the present invention.
2 is a cross-sectional view of the cast iron shown in FIG. 1 in a plan view (a) and a side view (b).
FIG. 3 is a chart showing the state of scratches on the surface of an oxygen-free copper wire manufactured using the manufacturing apparatus of FIG. 1;
[Explanation of symbols]
1 Oxygen-free copper wire manufacturing equipment
5 Tundish
23 Cast copper
25 Oxygen-free copper wire
31 Molten copper channel (molten copper channel)
33 Stirring means (degassing means)
33a, 33b, 33c, 33d Weir
A melting furnace
B Holding furnace
C cast iron
D belt caster type continuous casting machine
E Rolling machine
F Coiler

Claims (7)

Supplying molten copper to a belt caster type continuous casting machine, rolling a cast copper material derived from the belt caster type continuous casting machine, and continuously producing oxygen-free copper wire,
A molten copper production process for producing molten copper by burning in a reducing atmosphere of a melting furnace;
A molten copper transfer step of transferring the molten copper sent from the melting furnace to a tundish using a cast iron that can be sealed in a non-oxidizing atmosphere,
A degassing step of performing a dehydrogenation treatment by stirring the molten copper passing through the casting slag;
Silver in which silver is added so that the content of silver is 0.005 to 0.2 wt% to the molten copper in which the oxygen content is 3 to 10 ppm and the hydrogen content is 1 ppm or less in the degassing step An addition process;
A continuous casting process for continuously casting the molten copper added with silver to a belt caster type continuous casting machine;
Rolling the cast copper material formed by the belt caster type continuous casting machine ,
The degassing step is agitated by stirring the molten copper at least vertically by means of an upper dam provided on the upper side of the flow path and a lower dam provided on the lower side. Method. 2. The method for producing an oxygen-free copper wire according to claim 1, wherein in the degassing step, mixing of atmospheric gas before and after the dehydrogenation treatment is prevented by an upper weir provided on the upper side of the flow path . Supplying molten copper to a belt caster type continuous casting machine, rolling a cast copper material derived from the belt caster type continuous casting machine, and continuously producing an oxygen-free copper wire,
A melting furnace that burns in a reducing atmosphere to create molten copper;
A holding furnace for holding the molten copper sent from the melting furnace at a predetermined temperature;
A cast iron that seals the molten copper sent from the holding furnace in a non-oxidizing atmosphere and transfers it to the tundish;
The molten copper passing through the cast iron is agitated by meandering at least up and down by an upper weir provided on the upper side of the flow path and a lower weir provided on the lower side, and the dehydrogenation treatment of the molten copper is performed. Degassing means to perform;
Silver added with silver so that the content of silver is 0.005 to 0.2 wt% to the molten copper having an oxygen content of 3 to 10 ppm and a hydrogen content of 1 ppm or less by the degassing means Adding means;
A belt caster type continuous casting machine for continuously casting molten copper to which silver is added;
A rolling mill for rolling a cast copper material formed by the belt caster type continuous casting machine;
An apparatus for producing oxygen-free copper wire, comprising:   The cast iron is covered with an upper cover, and the upper cover is provided with an upper weir that extends downward and prevents mixing of atmospheric gas before and after the dehydrogenation treatment. An apparatus for producing an oxygen-free copper wire according to claim 3. An oxygen-free copper wire produced by the method for producing an oxygen-free copper wire according to claim 1 or 2 or using the device for producing an oxygen-free copper wire according to claim 3 or 4 , An oxygen-free copper wire containing 0.005 to 0.2 wt% of silver. The oxygen-free copper wire according to claim 5 , comprising 0.03 to 0.20 wt% of silver. The oxygen-free copper wire according to claim 6 , comprising 0.05 to 0.20 wt% of silver.

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