JP6027807B2 - Copper alloy trolley wire and method for producing copper alloy trolley wire - Google Patents

Description

  The present invention relates to a copper alloy trolley wire that is in sliding contact with a current collector such as a pantograph provided on a train or the like and supplies power to the train or the like.

A railway trolley wire used for trains, etc. is configured to be slidably contacted with a current collector such as a pantograph and supplied with power as described above, so that it has a certain strength, wear resistance, and electrical conductivity. It is necessary to ensure heat resistance.
Conventionally, as a trolley wire, as disclosed in Patent Document 1, for example, a trolley wire made of Sn-containing copper containing 0.25 to 0.35% by weight of Sn is provided. This Sn-containing copper is a solid solution strengthened copper alloy strengthened by solid solution of Sn in the copper matrix, and is excellent in wear resistance and the like.

In recent years, the speed of trains has been increased, but in high-speed railways such as the Shinkansen, if the train speed is faster than the propagation speed of waves generated on overhead lines such as trolley lines, There is a possibility that the contact between the current collector and the trolley wire becomes unstable, and power cannot be stably supplied.
Here, by increasing the overhead wire tension of the trolley wire, it is possible to increase the wave propagation speed in the trolley wire. Therefore, a trolley wire having higher strength than the conventional one is required.

  Thus, for example, Patent Documents 2 to 4 propose a trolley wire made of a copper alloy containing Cr, Zr, or the like. A copper alloy containing Cr, Zr, etc. is a precipitation-strengthened copper alloy whose strength is improved by precipitation and dispersion of a compound containing Cr or Zr as a main component in the matrix phase. It will be further improved.

Japanese Examined Patent Publication No. 59-043332 Japanese Patent Laid-Open No. 03-056632 JP 05-311284 A JP 07-266939 A

By the way, in the precipitation strengthening type copper alloy containing Cr, Zr and the like described in Patent Documents 2-4, Cr and Zr are dissolved in the matrix phase in the solution treatment step, and predetermined in the cold working step. After that, in the aging heat treatment step, a compound containing Cr or Zr as a main component is precipitated. Here, in a trolley wire made of a precipitation-strengthened copper alloy, the strength and conductivity change depending on the dispersion state of the precipitate. Therefore, by adjusting the heat treatment conditions in the aging heat treatment step, The distributed state is controlled.
However, in copper alloys containing Cr, Zr, etc., when cold working is performed after aging heat treatment, the performance such as conductivity changes greatly, so the aging heat treatment process is performed in a shape that approximates the final product. There is a problem that the shape cannot be sufficiently corrected after the aging heat treatment. For example, in the case of the grooved trolley wire shown in FIG. 1, it is necessary to perform an aging heat treatment after performing the groove processing.

  Further, as the traveling speed of the train increases, a large frictional force acts on the trolley wire, and the temperature of the trolley wire increases due to frictional heat. For this reason, improvement in heat resistance is demanded as compared with the prior art. That is, even when the temperature is as high as 200 ° C., it is necessary to have a sufficient tensile strength and ensure the overhead wire tension.

  The present invention has been made in view of the above-mentioned circumstances, and is excellent in strength, conductivity, wear resistance, heat resistance, and excellent in shape accuracy, and manufacturing of the copper alloy trolley wire. It aims to provide a method.

In order to solve the above-described problems, the copper alloy trolley wire according to the present invention includes Co; 0.12% by mass to 0.40% by mass, P; 0.040% by mass to 0.16% by mass, Sn Precipitates containing 0.005% by mass to 0.70% by mass, the balance being Cu and inevitable impurities, the average particle size being 10 nm or more, and the number of precipitates having a particle size of 5 nm or more being observed are a total of 90% or more, the initial tensile strength and tensile strength of _TS 0, 400 ℃ × 2 hours after holding a TS _1, heat resistance defined by _{hR = TS 1 / TS 0 ×} 100 HR is Ri der 90%, conductivity is 76% IACS or more, is characterized in that elongation is 5% or less.

  In the copper alloy trolley wire according to the present invention described above, Co: 0.12% by mass to 0.40% by mass, P: 0.040% by mass to 0.16% by mass, Sn: 0.005% by mass Since the composition contains 0.70% by mass or less and the balance is made of Cu and inevitable impurities, the precipitate made of a compound of Co and P is dispersed in the copper matrix. Thereby, it is possible to improve the strength and conductivity.

When Co and P are below the lower limit, the number of precipitates is insufficient, and the strength cannot be sufficiently improved. On the other hand, if Co and P exceed the upper limit values, there are many elements that do not contribute to the improvement of strength, which may cause a decrease in conductivity. For this reason, Co and P are set within the above-described range.
Sn is an element having an effect of improving strength by solid solution in a copper matrix. In addition, the effect of promoting the precipitation of precipitates containing Co and P as main components, and the heat resistance and corrosion resistance can be improved. In order to ensure that such effects are achieved, the Sn content needs to be 0.005 mass% or more. Further, when Sn is added excessively, the conductivity is lowered, so the Sn content needs to be 0.70 mass% or less.
Moreover, it is preferable that the said precipitation strengthening type copper alloy contains Ni; 0.01 mass% or more and 0.15 mass% or less further.
In the copper alloy wire having this configuration, since Ni is contained within the above-described range, the coarsening of crystal grains can be suppressed and the strength can be further improved.

Further, in the copper alloy trolley wire according to the present invention, the average particle size is 10 nm or more, and the number of precipitates having a particle size of 5 nm or more is 90% or more of the total precipitates to be observed. It becomes possible to improve electrical conductivity and heat resistance. Here, in the case where the particle size of the precipitate is less than 10 nm, in the subsequent cold working, the precipitate containing Co and P as main components is re-dissolved in the matrix phase, and the conductivity is lowered. I will let you.
As described above, in the copper alloy trolley wire of the present invention, the strength is further improved by cold working after the aging heat treatment, and therefore the shape is sufficiently corrected by performing the cold working after the aging heat treatment. Therefore, it is possible to provide a copper alloy trolley wire excellent in shape accuracy.

Furthermore, in the copper alloy trolley wire according to the present invention, the initial tensile strength is TS ₀ , and the tensile strength after holding at 400 ° C. × 2 hours is TS ₁ and is defined as HR = TS ₁ / TS ₀ × 100. Since the heat resistance HR is 90% or more, even if the temperature of the copper alloy trolley wire rises due to frictional heat, etc., sufficient tensile strength is secured, and the overhead tension of this copper alloy trolley wire Can be set high, and can be applied to high-speed railways.

The method for producing a copper alloy trolley wire according to the present invention is a method for producing the copper alloy trolley wire described above, wherein the copper alloy trolley wire is produced by a continuous casting and rolling step for continuously producing a copper rough drawing wire and the continuous casting and rolling step. A primary cold working step for processing the copper rough wire into a copper wire having a predetermined cross-sectional shape, an aging heat treatment step for performing an aging heat treatment on the copper wire, and the copper wire after the aging heat treatment step A secondary cold working step in which cold working is performed to obtain a copper alloy trolley wire having a predetermined cross-sectional shape, and a working rate in the secondary cold working step is 20% to 65%. It is characterized by being within the range.

According to the manufacturing method of the copper alloy trolley wire having this configuration, after the precipitate mainly composed of Co and P is deposited by the aging heat treatment step , the processing rate is 20% or more and 65% or less in the secondary cold working step . Thus, dislocation loops are formed in the precipitates, and the strength can be improved with certainty. Moreover, since cold working with a working rate of 20% or more is performed after the aging heat treatment step, the shape accuracy of the trolley wire can be improved.
Here, when the processing rate in the secondary cold working step is less than 20%, the strength may be insufficiently improved. Moreover, when the processing rate in the secondary cold working process exceeds 65%, there is a possibility that the electrical conductivity is lowered due to accumulation of dislocations and re-dissolution of precipitates. Therefore, from the viewpoint of ensuring strength and electrical conductivity, the processing rate in the secondary cold working process is set within a range of 20% to 65%.

  According to the present invention, it is possible to provide a copper alloy trolley wire excellent in strength, conductivity, and heat resistance and excellent in shape accuracy, and a method for producing the copper alloy trolley wire.

It is a section explanatory view of the copper alloy trolley wire which is an embodiment of the present invention. It is a flowchart of the manufacturing method of the copper alloy trolley wire which is embodiment of this invention. It is a schematic explanatory drawing of the continuous casting rolling equipment used with the manufacturing method of the copper alloy trolley wire which is embodiment of this invention.

Below, the manufacturing method of the copper alloy trolley wire and copper alloy trolley wire which concern on embodiment of this invention is demonstrated with reference to attached drawing.
In FIG. 1, an example of the copper alloy trolley wire 1 which is embodiment of this invention is shown.
As shown in FIG. 1, the copper alloy trolley wire 1 according to this embodiment is a grooved trolley wire in which a groove 2 for mounting a metal fitting is formed. The copper alloy trolley wire 1 includes a first arc portion 3 provided on one side (lower side in FIG. 1) of the groove 2 and a second arc portion provided on the other side (upper side in FIG. 1) of the groove 2. 4 and the first arc portion 3 is in sliding contact with the pantograph.
Here, the trolley wire for railway is standardized by the cross-sectional area, and the cross-sectional area is 110 mm ² in the copper alloy trolley wire 1 according to the present embodiment.

This copper alloy trolley wire 1 has Co: 0.12 mass% or more and 0.40 mass% or less, P: 0.040 mass% or more and 0.16 mass% or less, Sn: 0.005 mass% or more and 0.70 mass% %, And the balance is made of Cu and a copper alloy having a composition with inevitable impurities.
Moreover, it is preferable that the said precipitation strengthening type copper alloy contains Ni; 0.01 mass% or more and 0.15 mass% or less further.
In addition, in this copper alloy, 0.002 mass% or more and 0.5 mass% or less Zn, 0.002 mass% or more and 0.25 mass% or less Mg, 0.002 mass% or more and 0.25 mass% % Or less of Ag and 0.001% by mass or more and 0.1% by mass or less of Zr may contain any one or more of them.
In the copper alloy wire having this configuration, one or more of Zn, Mg, Ag, and Zr are contained in the above-mentioned range, so that these elements form a compound with sulfur (S). Thus, it is possible to suppress sulfur (S) from being dissolved in the copper parent phase and to suppress deterioration of mechanical properties such as strength.
The reason why the content of each element is set within the above range will be described below.

(Co and P)
Co and P are elements that form precipitates dispersed in the copper matrix.
Here, when the Co content is less than 0.12% by mass and the P content is less than 0.040% by mass, the number of precipitates may be insufficient and the strength may not be sufficiently improved. is there. On the other hand, when the Co content exceeds 0.40% by mass and the P content exceeds 0.16% by mass, there are many elements that do not contribute to the improvement of the strength, resulting in a decrease in conductivity. There is a risk of inviting.
For this reason, the Co content is set in the range of 0.12 mass% to 0.40 mass%, and the P content is set in the range of 0.040 mass% to 0.16 mass%.

(Sn)
Sn is an element having an action of improving strength by being dissolved in a copper matrix. In addition, it has an effect of promoting precipitation of precipitates containing Co and P as main components and an effect of improving heat resistance and corrosion resistance.
Here, when content of Sn is less than 0.005 mass%, there exists a possibility that the effect mentioned above may not be achieved reliably. On the other hand, when the Sn content exceeds 0.70% by mass, the conductivity may not be ensured.
For this reason, the Sn content is set in the range of 0.005 mass% or more and 0.07 mass% or less.

(Ni)
Ni is an element that can replace a part of Co and has an effect of suppressing coarsening of crystal grains.
Here, when the content of Ni is less than 0.01% by mass, the above-described functions and effects may not be reliably achieved. On the other hand, when the Ni content exceeds 0.15% by mass, the conductivity may not be ensured.
For this reason, when it contains Ni, it is preferable to make content of Ni into the range of 0.01 mass% or more and 0.15 mass% or less.

(Zn, Mg, Ag, Zr)
Elements such as Zn, Mg, Ag, and Zr are elements having an effect of generating a compound with sulfur (S) and suppressing the solid solution of sulfur (S) in the copper matrix.
Here, when the content of elements such as Zn, Mg, Ag, and Zr is less than the above lower limit value, the effect of suppressing the solid solution of sulfur (S) in the copper matrix is sufficiently successful. I can't let you. On the other hand, when the content of elements such as Zn, Mg, Ag, and Zr is larger than the above-described upper limit values, the conductivity may not be ensured.
For this reason, when elements, such as Zn, Mg, Ag, and Zr, are contained, it is preferable to be in the above-mentioned range.

Further, in the copper alloy trolley wire 1 according to the present embodiment, the average particle size is 10 nm or more, and the number of precipitates having a particle size of 5 nm or more is 90% or more of the total precipitates to be observed. .
Here, the observation of the precipitate was performed as follows. Observation was performed with a transmission electron microscope at magnifications of 150,000 and 750,000 times, the area of the precipitate was calculated, and the equivalent circle diameter was calculated as the particle diameter. A precipitate having a particle size of 11 to 100 nm at a magnification of 150,000 times and a precipitate having a particle size of 1 to 10 nm at a magnification of 750,000 times were measured. Since observations at a magnification of 750,000 cannot clearly discriminate precipitates less than 1 nm, the total number of precipitates observed is the number of precipitates having a particle size of 1 nm or more. Observation with a transmission electron microscope was performed with a visual field area of about 4 × 10 ⁵ nm ² when the magnification was 150,000 times and with a visual field area of about 2 × 10 ⁴ nm ² when the magnification was 750,000 times.

In the copper alloy trolley wire 1 according to the present embodiment, the initial tensile strength is TS ₀ , and the tensile strength after holding at 400 ° C. × 2 hours is TS ₁ HR = TS ₁ / TS ₀ × 100 The defined heat resistance HR is 90% or more.
In the present embodiment, the tensile strength of the copper alloy trolley wire 1 was measured according to JIS Z 2241. Further, the tensile strength TS ₁ after the heat treatment was measured at room temperature after being held at 400 ° C. for 2 hours.

Next, the manufacturing method of the above-mentioned copper alloy trolley wire 1 will be described. FIG. 2 shows a flow chart of a method for manufacturing a copper alloy trolley wire 1 according to an embodiment of the present invention.
First, the copper roughing wire 50 made of the copper alloy is continuously produced by a continuous casting and rolling method (continuous casting and rolling step S01). In this continuous casting and rolling step S01, for example, the continuous casting and rolling equipment shown in FIG. 3 is used.

  The continuous casting and rolling equipment shown in FIG. 3 has a melting furnace A, a holding furnace B, a casting rod C, a belt wheel type continuous casting machine D, a continuous rolling device E, and a coiler F.

  In this embodiment, a shaft furnace having a cylindrical furnace body is used as the melting furnace A. A plurality of burners (not shown) are arranged in a multistage shape in the vertical direction at the lower part of the furnace body. And the electrolytic copper which is a raw material is inserted from the upper part of a furnace main body, is melt | dissolved by the combustion of the said burner, and a copper melt is continuously produced.

  The holding furnace B is for temporarily storing the molten copper produced in the melting furnace A while holding it at a predetermined temperature, and sending a certain amount of the molten copper to the casting iron C.

  The cast iron C is for transferring the molten copper sent from the holding furnace B to the tundish 11 disposed above the belt wheel type continuous casting machine D. The cast iron C is sealed with, for example, an inert gas such as Ar or a reducing gas. The cast iron C is provided with degassing means (not shown) for stirring the molten copper with an inert gas to remove oxygen and the like in the molten metal.

  The tundish 11 is a storage tank provided for continuously supplying molten copper to the belt wheel type continuous casting machine D. A pouring nozzle 12 is disposed at the end of the tundish 11 in the flow direction of the molten copper, and the molten copper in the tundish 11 passes to the belt wheel continuous casting machine D via the pouring nozzle 12. It is set as the structure supplied.

  Here, in the present embodiment, an alloy element addition means (not shown) is provided in the cast iron C and the tundish 11, and the above-mentioned elements (Co, P, Sn) are added to the molten copper. It is said that.

  The belt wheel type continuous casting machine D includes a cast wheel 13 having a groove formed on the outer peripheral surface thereof, and an endless belt 14 that is circulated so as to contact a part of the outer peripheral surface of the cast wheel 13. . In the belt wheel type continuous casting machine D, molten copper is injected into the space formed between the groove and the endless belt 14 via the pouring nozzle 12, and the molten copper is cooled and solidified. The rod-shaped cast copper material 21 is continuously cast.

A continuous rolling device E is connected to the downstream side of the belt wheel type continuous casting machine D. The continuous rolling apparatus E continuously rolls the cast copper material 21 produced from the belt wheel type continuous casting machine D to produce a copper roughing wire 50 having a predetermined outer diameter.
The copper roughing wire 50 produced from the continuous rolling device E is wound around the coiler F via the cleaning / cooling device 15 and the flaw detector 16.
Here, the outer diameter of the copper roughing wire 50 produced by the above-mentioned continuous casting and rolling equipment is, for example, 8 mm or more and 30 mm or less, and is 27 mm in this embodiment.
In this continuous casting and rolling step S01, the cast copper material 21 is held at a relatively high temperature of, for example, 800 ° C. to 1000 ° C., so that many elements such as Co and P are dissolved in the copper matrix. become.

  Next, as shown in FIG. 2, cold working is performed on the copper roughing wire 50 produced by the continuous casting and rolling step S01 (primary cold working step S02). In the primary cold working step S02, a copper wire having a predetermined cross-sectional shape is processed by a die drawing method, a roll rolling method, a swaging process, or the like. At this time, an oil-based lubricant is used for the purpose of reducing machining resistance, reducing wear of dies and rolls, cooling materials, and the like.

Next, the copper wire is stripped (skin stripping step S03). In the skinning step S03 , a surface layer of 0.1 to 0.5 mm, preferably 0.1 to 0.2 mm, is removed using a skinning die. The copper wire obtained by the skinning step S03 has a diameter of about 13 to 22 mm, and is 18 mm in this embodiment.

Next, an aging heat treatment is performed on the copper wire after the skinning step S03 (aging heat treatment step S04). Through this aging heat treatment step S04, a precipitate made of a compound containing Co and P as main components is deposited.
Here, in the aging heat treatment step S04, the heating rate is 50 ° C./hour to 300 ° C./hour, the heat treatment temperature is 300 ° C. to 600 ° C., and the holding time is 0.5 hours to 6 hours. The

Next, cold working is performed on the copper wire after the aging heat treatment step S04 to obtain a copper alloy trolley wire having a predetermined cross-sectional shape (secondary cold working step S05).
Here, the processing rate in the secondary cold working step S05 is set to be in the range of 20% to 65%.
In this secondary cold working step S05, a groove processing is performed on a copper wire having a circular cross section to obtain a copper alloy trolley wire 1 having a cross sectional shape shown in FIG.

  According to the copper alloy trolley wire 1 and the manufacturing method of the copper alloy trolley wire 1 of the present embodiment configured as described above, Co: 0.12% by mass or more and 0.40% by mass or less, P; 040 mass% or more and 0.16 mass% or less, Sn; 0.005 mass% or more and 0.70 mass% or less are included, and the balance is made of Cu and unavoidable impurities, so in the copper matrix Precipitates made of a compound of Co and P are dispersed, and the strength and electrical conductivity can be improved.

  Here, in the present embodiment, the Co content is set within a range of 0.12% by mass to 0.40% by mass, and the P content is set within a range of 0.040% by mass to 0.16% by mass. Therefore, the number of precipitates is ensured, the strength can be sufficiently improved, and there is not a large amount of excess Co and P that do not contribute to the improvement of the strength, so that the conductivity can be ensured.

  In addition, since the Sn content is 0.005% by mass or more, the strength can be improved by solid solution in the copper matrix, and precipitation of precipitates containing Co and P as main components is also possible. It is possible to promote heat resistance and corrosion resistance. On the other hand, since the Sn content is 0.70% by mass or less, a decrease in conductivity can be suppressed.

  Moreover, in this embodiment, 0.002 mass% or more and 0.5 mass% or less of Zn, 0.002 mass% or more and 0.25 mass% or less of Mg, 0.002 mass% or more of 0.002 mass% or more, as needed. It is set as the structure containing any 1 or more types among 25 mass% or less Ag and 0.001 mass% or more and Zr of 0.1 mass% or less. When such an element is added, the solid solution of S in the copper matrix can be prevented, and the performance degradation due to S can be prevented. Furthermore, the strength can be further improved by these elements.

In the copper alloy trolley wire 1 according to the present embodiment, the average particle size is 10 nm or more, and the number of precipitates having a particle size of 5 nm or more is 90% or more of the total precipitates to be observed. Strength, conductivity, and heat resistance can be improved.
In addition, in the copper alloy trolley wire 1 according to the present embodiment, the strength is further improved by cold working after the aging heat treatment, so that the shape is sufficiently corrected by performing the cold working after the aging heat treatment. Therefore, it is possible to provide the copper alloy trolley wire 1 having excellent shape accuracy.

Furthermore, in the copper alloy trolley wire 1 according to the present embodiment, the initial tensile strength is TS ₀ , and the tensile strength after holding at 400 ° C. × 2 hours is TS ₁ HR = TS ₁ / TS ₀ × 100 Since the defined heat resistance HR is 90% or more, even if the temperature of the copper alloy trolley wire 1 rises due to frictional heat or the like, sufficient tensile strength is secured, and this copper alloy trolley wire The overhead wire tension of 1 can be set high and can be applied to high-speed railways.

  In addition, the method for manufacturing the copper alloy trolley wire 1 according to the present embodiment includes an aging heat treatment step S04 and a secondary cold working step S05 performed after the aging heat treatment step S04. In the next cold working step S05, since the working rate is 20% or more and 65% or less, the strength can be reliably improved and the electrical conductivity can be secured. That is, when the processing rate in the secondary cold working step S05 is less than 20%, the strength may be insufficiently improved. Moreover, when the processing rate in secondary cold working process S05 exceeds 65%, there exists a possibility that electrical conductivity may fall by accumulation | storage of a dislocation | rearrangement and re-dissolution of a precipitate.

  Furthermore, in this embodiment, since the secondary cold working step S05 is provided with an aging treatment step S04 for depositing precipitates by heat treatment at 300 ° C. to 600 ° C. for 0.5 hours to 6 hours. The size and density of the precipitates dispersed in the copper matrix can be adjusted. For example, the number of precipitates having an average particle size of 10 nm or more and a particle size of 5 nm or more is observed. It can be 90% or more of the entire precipitate, and the strength can be improved.

  Moreover, in the manufacturing method of the copper alloy trolley wire 1 which is this embodiment, since the copper rough drawing wire 50 is produced by the continuous casting rolling process S01, the copper rough drawing wire 50 can be produced efficiently. Moreover, since it will be hold | maintained for a fixed time, for example in a high temperature state of 800-1000 degreeC, elements, such as Co and P, will be dissolved in the mother phase of copper, and it is necessary to perform solution treatment separately. There is no.

As mentioned above, although embodiment of this invention was described, this invention is not limited to this, It can change suitably in the range which does not deviate from the technical idea of the invention.
For example, in the present embodiment, the copper alloy trolley wire having a cross-sectional shape shown in FIG. 1 has been described, but the present invention is not limited to this, and a copper alloy trolley wire having another cross-sectional shape may be used. Moreover, although demonstrated as a trolley wire for railroads, it is not limited to this, You may be used for conveyance machines, such as a crane.

Moreover, although this embodiment demonstrated as what manufactures a copper rough drawing wire by a continuous casting rolling process, it is not limited to this, A cylindrical ingot (billet) is produced and this ingot is extruded. -You may produce a rough copper wire by cold working. However, when a copper roughing wire is produced by an extrusion method, it is necessary to perform a solution treatment separately. Furthermore, even if it is a case where it manufactures by a continuous casting rolling process, you may implement a solution treatment with respect to a copper rough drawing wire.
In the present embodiment, the continuous casting and rolling process is described as being performed using the belt wheel type casting machine shown in FIG. 3, but the present invention is not limited to this, and other continuous casting methods are adopted. Also good.

Below, the result of the confirmation experiment performed in order to confirm the effectiveness of this invention is demonstrated.
Using a continuous casting and rolling facility equipped with a belt wheel type continuous casting machine, a copper roughing wire (27 mm in diameter) made of a copper alloy having the composition shown in Table 1 was produced. The copper cold drawn wire was subjected to primary cold working to a diameter of 20 mm, and after skinning, an aging heat treatment was performed under the conditions shown in Table 1. Thereafter, conducted between secondary cold working under the conditions shown in Table 1, were prepared grooved trolley wire cross-sectional area 110 mm ^2.

And the deposit was observed using the manufactured grooved trolley wire. Precipitation is observed using transmission electron images of a transmission electron microscope (model name: TEM: Hitachi, H-800, HF-2000, HF-2200, and JEOL JEM-2010F). The equivalent particle diameter was calculated from the area. Note that the magnification was 150,000 times and 750,000 times, and the observation was performed in the measurement visual fields of about 4 × 10 ⁵ nm ² and about 2 × 10 ⁴ nm ² , respectively. Then, the average particle size of the precipitates and the proportion of the precipitates having a particle size of 5 nm or more among the observed precipitates were calculated. The results are shown in Table 2.

Moreover, heat resistance HR, tensile strength, elongation, and electrical conductivity were evaluated using the manufactured grooved trolley wire.
Heat resistance HR is the initial tensile strength and tensile strength of _TS 0, 400 ℃ × 2 hours after holding a TS _1, are as defined by _{HR = TS 1 / TS 0 ×} 100, JIS Z 2241 In accordance with the above, using an AG-100kNX manufactured by Shimadzu Corporation, the initial tensile strength TS ₀ was measured and calculated as the tensile strength TS ₁ after holding at 400 ° C. × 2 hours.
The tensile strength and elongation were also measured using AG-100kNX manufactured by Shimadzu Corporation in accordance with JIS Z 2241 as described above.
The electrical conductivity was measured by a double bridge method according to JIS h 0505.
In addition, heat resistance, tensile strength, elongation, and conductivity were measured for tough pitch copper as Conventional Example 1 and Cu-0.3 wt% Sn as Conventional Example 2.
The evaluation results are shown in Table 2.

In Comparative Example 1 in which the contents of Co and P exceed the upper limit of the present invention, it is confirmed that the conductivity is low.
In Comparative Example 2 in which the contents of Co and P were less than the lower limit of the present invention, the tensile strength was insufficient.
In Comparative Example 3 where the Sn content exceeded the upper limit of the present invention, it was confirmed that the conductivity was low.
In Comparative Example 4 in which the Sn content was less than the lower limit of the present invention, the tensile strength was insufficient.
In Comparative Example 5, in which the average particle size of the precipitates and the ratio of the total number of precipitates in which the number of precipitates having a particle size of 5 nm or more was observed deviated from the scope of the present invention, the conductivity was low.
Further, in the conventional examples 1 and 2, the tensile strength is insufficient and the heat resistance is insufficient.

On the other hand, in Example 1-9 of this invention, it is confirmed that it is excellent in intensity | strength, electrical conductivity, and heat resistance.
From the results of the above confirmation experiment, it was confirmed that according to the present invention, it is possible to stably provide a copper alloy trolley wire excellent in strength, electrical conductivity, and heat resistance.

1 Copper Alloy Trolley Wire 2 Groove 3 First Arc Part 4 Second Arc Part

Claims (2)

Co: 0.12 mass% or more and 0.40 mass% or less, P: 0.040 mass% or more and 0.16 mass% or less, Sn; 0.005 mass% or more and 0.70 mass% or less, and the balance is Cu And inevitable impurities,
The average particle size is 10 nm or more, and the number of precipitates having a particle size of 5 nm or more is 90% or more of the total precipitates observed,
The initial tensile strength is TS ₀ , and the tensile strength after holding at 400 ° C. × 2 hours is TS ₁ ,
_{HR = TS 1 / TS 0 ×} 100
In Ri defined der heat resistance HR 90% or more by,
A copper alloy trolley wire having an electrical conductivity of 76% IACS or more and an elongation of 5% or less . A method for producing a copper alloy trolley wire according to claim 1,
A continuous casting and rolling step for continuously producing a copper roughing wire; a primary cold working step for processing the copper roughing wire produced by the continuous casting and rolling step into a copper wire having a predetermined cross-sectional shape; and An aging heat treatment step for performing an aging heat treatment on the copper wire, and a secondary cold working to form a copper alloy trolley wire having a predetermined cross-sectional shape by performing a cold work on the copper wire after the aging heat treatment step. And having a process
A method for producing a copper alloy trolley wire, wherein a processing rate in the secondary cold working step is in a range of 20% to 65%.

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