JPH0356632A - Copper alloy for trolley wire - Google Patents

Abstract

PURPOSE:To obtain the copper alloy for a trolley wire having excellent current collecting-sliding wear resistance, heat resistance, heat radiating properties and strength at low cost by specifying the compsn. constituted of Zr, Cr and Cu and furthermore restricting the content of inevitable impurities such as Sn and Si. CONSTITUTION:The compsn. contg., by weight, >0.15 to 0.35% Zr and >0.3 to 1.2% Cr, furthermore contg., at need, total <=1.5% of one or more kinds among <=0.3% Mg, <=1.5% Zn, <=0.2% Ag and <=0.5% Cd and the balance Cu with inevitable impurities in which the content of Sn is restricted to <=100ppm, Si to <=50ppm, P to <=50ppm, Fe to <=100ppm, Ni to <=100ppm, Pb to <=20ppm, As to <=20ppm, Sb to <=20ppm, Bi to <=20ppm and S to <=10ppm is formed, by which the copper alloy for a trolley wire in which mechanical and thermal damage and wear are reducible and having various excellent characteristics can be obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a copper alloy for trolley wires that is excellent in current collection sliding wear resistance, heat resistance, heat dissipation properties, and strength.

[Conventional technology]

Conventionally, pure copper, typified by tough pitch copper, has been used for trolley wires for transportation, typically tram lines.
Due to the trend toward high-speed transportation, Ag-containing copper and Sn-containing copper have come to be used. However, with the development of high-speed, large-capacity means of transportation such as the Shinkansen, conventional materials have caused significant mechanical and thermal damage and wear to the trolley wire, resulting in problems such as high-speed current collection performance, high-speed current collection noise, and maintenance costs. There is a need for improvement in this respect.

[Problem to be solved by the invention]

The conventionally used Ag-based copper cannot cope with the current high speeds due to its wear resistance, and the commonly used Sn-containing copper is superior to the Ag-based copper in terms of wear resistance. However, a better trolley wire is desired from the viewpoint of increased speed, increased wear due to increased capacity, and heat resistance strength due to heat generation.

[Means for Solving the Problems] In view of this, and as a result of various studies, the present invention has developed a copper alloy for trolley wires that is excellent in current collection sliding wear, heat resistance strength, heat dissipation properties, etc.

That is, one of the alloys of the present invention has a 0. l5wl% (hereinafter referred to as w1%)
(abbreviated as %) and less than 0.35% of Zr and more than 0.3% and less than 1.2% of Cr, and the balance is Cu and SnI.
OIIIP1 or less, S i 50ppIB or less, P
SOppm or less, Fe 100ppm or less, Ni
100ppm or less, Pb 20ppi or less, A s 2D
ppr @ or less, S b 2 Opp or less, B j 20
It is characterized by consisting of unavoidable impurities limited to less than ppm and less than S10p.

Ru.

Another aspect of the present invention is more than 0.15% and 0.35%
Contains the following Zr and more than 0.3% but not more than 1.2% of Cr, further contains Mg not more than 0.3%, Znl. 5% or less, AgO.
2% or less, CdO. Contains any one or more of two or more types in a total of 1.5% or less within a range of 5% or less, and the balance is Cu and Sn
1001Uffi or less, S i SOppi or less, P
50 ppm or less, F e ]0 [1 ppm or less, N i
lOQppm or less, P b 20pptp or less, A
8 20ppm or less, Sb 20ppm or less, B i 2
It is characterized by consisting of unavoidable impurities limited to 0 ppm or less and S to 10 ppm or less.

[Function J] The reason why the alloy assembly is limited as described above in the present invention is as follows.

The Zr content was limited to more than 0.15% and less than 0.35%, and the Cr content was limited to more than 0.63% and less than 1.2%.
Both r and Cr exist as dispersed particles in Cu, which improves wear resistance and further improves heat resistance strength, and within the scope of the present invention, it is highly effective and can be manufactured easily and inexpensively. I can do it. However, if the content is below the lower limit, although the above effects can be obtained, it is difficult to control the content, leading to deterioration of manufacturability, and if the content exceeds the upper limit, the above effects will not improve much, resulting in a decrease in castability. This is because it leads to a decrease in conductivity (heat dissipation).

Next, in the impurities, Sn is 100 pplB or less and Si is 50 pplB.
p+t or less, P 50ppm or less, Fe 100ppm
Ni below! 00ppm or less, pb 20ppm or less, As 20ppm or less, sb 20ppm or less, Bi
The reason for limiting S to below 2[1ppn and S to below 1Oppr@ is that although Sn has the function of improving wear resistance, it has a large effect of impairing the heat dissipation characteristic of the present invention. Since P tends to form coarse precipitates with Cr, it is limited in order to reduce the amount of Cr that contributes to wear resistance and reduce its effectiveness. Also, FeSNi
Pb1As, Sb. ．． For Bi,S, C
It is restricted because it exists as coarse particles in u or concentrates at grain boundaries, causing reheat cracking or hot working cracking during hot working, and impairing the integrity of the trolley wire surface. .

Next, the Mg content is 0.3% or less, and the Zn content is 1.5%.
Below, the Ag content is 0.2% or less, and the Cd content is 0.5%.
The reason why we have limited the total content of any one or more types within the range of 1.5% or less is that these include Mg1Ag,C
This is because Zn improves heat resistance and wear resistance, and Zn improves corrosion resistance and arc resistance, increasing the life cycle of the trolley wire, but if added above the upper limit, it reduces heat dissipation.

The alloy of the present invention is indirectly or directly formed into a copper alloy solid solution by hot underwater extrusion or continuous casting using a water-cooled mold, and then processed into a trolley wire, heat treated, etc.

〔Example〕

The present invention will be explained in detail below with reference to Examples.

After melting a copper metal with a limited impurity concentration and deoxidizing the molten metal with P (if it contains Zn, Zn may be used) with the P concentration in the molten metal controlled to be 50 ppm or less, MgSAg
．． Cd and Zn were added and melted, and then C' and Zr were added to produce an alloy having the composition shown in Table 1. After thorough melting and stirring, it was cast into an ingot with a diameter of 20 Qmφ.

After heating this to 980°C and holding it for 0.5 hours, hot water-cooling extrusion was performed to obtain a rough drawn wire with a diameter of 25 mm, which was then sequentially subjected to surface grinding, cold wire drawing, and aging heat treatment to increase the cross-sectional area. Processed into 170si grooved trolley wire. Regarding this, tensile strength, heat resistance, current collection sliding abrasion resistance, and arc resistance were investigated.

The results are shown in Table 2.

Tensile strength Saha, JI3222411. :Based on room temperature (20
℃). Regarding heat resistance, the material was heated to a temperature of 400° C. and the tensile strength at that time was measured.

As a substitute for heat dissipation, conductivity is jIS11.
Pof1 was determined by 05 (15).

The current collection sliding abrasion resistance was measured by placing the test materials in a ring shape on a disk with a diameter of 5 m, and contacting them with a pantograph equipped with a copper-based sintered alloy as a sliding plate with an immediate lifting force of 5 kgl.
It was slid without lubrication at a speed of 50 km/h while being energized, and the amount of abrasion after 10,000 strokes was measured.

Regarding arc resistance, check whether there is a steady voltage between the copper-based sintered metal contact plate and one line of the test trolley. ! EAC5 (IA is energized, contact and disconnection are repeated 200 times, an arc is generated,
The amount of wear at that time was measured.

As is clear from Tables 1 and 2, it can be seen that the trolley wire made of the alloy of the present invention has superior properties compared to the trolley wire made of the conventional alloy. On the other hand, it can be seen that comparative alloys outside the composition range of the present alloy are inferior in one or more of the properties as a trolley wire. [Effects of the Invention] As described above, according to the present invention, it is possible to achieve high speed and large capacity. It has remarkable industrial effects, such as providing a trolley wire with excellent current collection sliding abrasion resistance, strength, and heat resistance.

Claims (2)

[Claims] (1) More than 0.15wt% and less than 0.35wt% Zr
Contains more than 0.3 wt% and less than 1.2 wt% of Cr,
Remaining Cu and Sn: 100ppm or less, Si: 50ppm or less, P: 50ppm or less, Fe: 100ppm or less, Ni: 10
0ppm or less, Pb 20ppm or less, As 20ppm or less, Sb 20ppm or less, Bi 20ppm or less, S10
A copper alloy for a trolley wire, characterized in that it contains unavoidable impurities limited to ppm or less. (2) More than 0.15wt% and less than 0.35wt% Zr
Contains more than 0.3 wt% and less than 1.2 wt% of Cr,
Furthermore, Mg 0.3 wt% or less, Zn 1.5 wt% or less, A
Contains a total of 1.5 wt% or less of any one or more types within the range of g0.2wt% or less and Cd0.5wt% or less,
Remaining Cu and Sn: 100ppm or less, Si: 50ppm or less, P: 50ppm or less, Fe: 100ppm or less, Ni: 10
0 ppm or less, Pb 20 ppm or less, As 20 ppm or less, Sb 20 ppm or less, Bi 20 ppm or less, S10
A copper alloy for a trolley wire, characterized in that it contains unavoidable impurities limited to ppm or less.