JPH04365823A - Production of slider for current collector - Google Patents

Abstract

PURPOSE:To produce the slider for the current collector excellent in wear resistance, arc resistance and energizing characteristic by injecting the melt of Al or Al alloy uniformly dispersed with ceramic particles into metallic molds, then pressurizing and solidifying the melt. CONSTITUTION:The particles of ceramics, such as SiC, Al2O3, TiC, and B4C, are added into the melt of the Al or Al alloy and are uniformly dispersed therein by stirring. The melt of the ceramic particle-contg. Al metal is injected from a sprue 5 into the casting cavity of the split metallic molds 2 consisting of a stationary mold 2A and a moving mold 2B and is solidified under pressurization; thereafter, the molds are knocked out to produce the slider for the current collector. The slider which is light in weight, is excellent in wear resistance and arc resistance at the time of contact and sliding with a trolley wire and has the excellent energizing characteristic similar to the energizing characteristic of a Cu slider is obtd.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a contact plate used in a current collector.

0002

2. Description of the Related Art Since a slider plate for a current collector slides in contact with a trolley wire, it is required to have excellent wear resistance, arc resistance, and current conductivity. Currently, contact plates made of copper-based or iron-based sintered alloys are widely used to meet these demands. The standard composition of a copper-based contact plate is 80-85% Cu, 9-12% Sn, F.
e3-6%, C2-5%, and the standard composition of iron-based contact plates is Fe77-82%, Cu8-10%, Sn1-5%.
2%, Pb 4-7%, and C5-7%.

[0003]Requirements for slider plates have become more severe as the speed of vehicles has increased in recent years, and new emphasis has been placed on the ability to follow trolley wires. If the tracking ability of the trolley wire is insufficient, there is a problem that the wire will become detached more frequently during high-speed running, causing frequent arcing, which not only increases the wear and tear of the contact plate and the trolley wire, but also causes radio wave interference. . Since the slider plates currently in use are mainly composed of copper or iron, which has a high specific gravity, the slider plates themselves have a large mass, making it difficult to improve their ability to follow the trolley wire.

[0004] In order to improve this, a contact plate is made of a composite material whose main component is lightweight and highly conductive aluminum or aluminum alloy, with ceramic particles dispersed therein for the purpose of imparting wear resistance. It is seen as promising (Patent Application No. 1-221833).

[0005]

[Problem to be solved by the invention] This newly proposed aluminum-based contact plate is extremely lightweight, and has been confirmed to have performance equivalent to or better than conventional copper-based or iron-based contact plates. However, a suitable method for producing it industrially has not yet been developed. An object of the present invention is to provide a method for industrially manufacturing a slide plate made of an aluminum-based composite material as described above.

[0006]

[Means for Solving the Problems and Their Effects] One manufacturing method provided by the present invention is to mix ceramic particles into a molten aluminum or aluminum alloy while stirring and uniformly disperse the aluminum, and then to The method is characterized in that the ceramic particle-dispersed molten metal is molded into a plate shape (including a shape that takes cutting or grinding allowance into account).

The purpose of stirring the molten metal is to uniformly disperse the ceramic particles. It is preferable to adopt the following method for molding.

[0008] The first method is to clamp a split mold having a slider-shaped cavity at a predetermined pressure, and then pour ceramic particle-dispersed molten metal into the mold and solidify it under pressure. In this case, the pressing force of the molten metal is
500 to 2000 kgf/cm2 is effective.

[0009] The second method is to pour a molten metal in which ceramic particles are dispersed into a mold having a cavity in the form of a slide plate and solidify it. As the mold, metal molds and various sand molds can be used.

The third method is to have a sprue in the center, and a plurality of mold spaces in the form of strips are evenly arranged around this sprue, and this mold space is communicated with the sprue through radial hot water passages. This method involves using a centrifugal casting device, in which ceramic particle-dispersed molten metal is injected through the sprue while rotating the centrifugal casting device around the sprue, and the molten metal is solidified under centrifugal force.

[0011] SiC particles, Al2 O3 particles, etc. are generally used as ceramic particles, but since these particles have a higher specific gravity than aluminum, when a contact plate is manufactured using this method, the particles are separated from the outer periphery by centrifugal force before solidification. They may gather on the side and cause segregation. In consideration of this point, it is desirable to arrange the mold so that the sliding surface of the slide plate, which requires wear resistance, is located on the outer peripheral side.

Another manufacturing method provided by the present invention is
Ceramic particles are mixed into the aluminum or aluminum alloy molten metal while stirring, and after uniformly dispersing it, the ceramic particle dispersed molten metal is solidified to create a composite material ingot, and this ingot is shaped into a plate. It is characterized by plastic working.

[0013] As a processing method, (1) the ingot shape is made into a cylindrical billet, this billet is extruded, and then cut;
A method of forging the ingot into a cylindrical billet, extrusion molding this billet, cutting it into the shape of a slat, and ■ A method of forging the ingot into a rectangular parallelepiped cake. There is a method in which the material is rolled, then cut, and forged into the shape of a slider.

Still another manufacturing method provided by the present invention is to mix and uniformly disperse ceramic particles and aluminum powder or aluminum alloy powder, deaeration,
After solidification, it is characterized by being plastically worked into a predetermined slider shape.

[0015] The above mixing method includes a mechanical method using a device such as a V-shaped mill, a ball mill, a vibration mill, an attritor, etc., or a method after uniformly dispersing the mixture by stirring in a liquid such as water or alcohol. , deliquification, drying methods, etc. can be used.

[0016] Further, as a deaeration and solidification method, the mixed powder is filled into a metal can with an exhaust pipe, the can is vacuumed, the can is sealed, and the can is cold compressed and hot pressed. After that, a hot pressing method, a vacuum hot pressing method, a HIP (hot isostatic pressing) method, etc. can be used. Further, as a method of plastic working, extrusion processing, rolling processing, drawing processing, forging processing, etc. can be used.

[0017]

EXAMPLES Examples of the present invention will be described in detail below. Example 1 SiC particles with an average particle diameter of 20 μm were added little by little to a molten ADC10 alloy heated to 750°C while stirring, and the total amount added was 15% by volume.A
A DC10 alloy molten metal was obtained.

On the other hand, a split mold 2 as shown in FIG. 7 was prepared which had a cavity having the same shape as the contact plate shown in FIGS. 1 and 2. This split mold 2 consists of a fixed mold 2A and a movable mold 2B, with a core pin 3 and a knockout pin 4 on the fixed mold 2A side.
It has a molten metal inlet 5 below the dividing surface.

After the split mold 2 is clamped, the Si
The C particle-dispersed molten metal was injected from the injection port 5 at an injection speed of about 70 mm/sec, and solidified under pressure. After demolding, the unnecessary solidified portion of the injection port is cut and removed, and the resulting cast product is coated with T6
After treatment, the sliding surface was lightly cut and holes were bored. As a result, it was possible to manufacture a slider plate 1 made of a composite material of SiC particles and ADC10 alloy and having the shape shown in FIGS. 1 and 2.

Furthermore, by using the same method as above, using TiC particles and Al2 O3 particles instead of SiC particles, it was possible to produce a good contact plate.

Example 2 SiC particle dispersion ADC10 obtained in the same manner as in Example 1
The molten alloy was poured into a sand mold having the same mold space as the contact plate shown in FIGS. 3 and 4 and allowed to solidify. Unnecessary parts of the obtained cast product were removed and T6 treatment was performed. As a result, the slider plate 1 having the shape shown in FIGS. 3 and 4 could be manufactured.

Although the obtained slider plate had more porosity than ordinary sand casting, it was sufficiently durable for use as a slider plate. It is also possible to manufacture a slider board in the same way by using a plaster mold or a metal mold instead of a sand mold.

Embodiment 3 A sprue is provided in the center, and around this sprue there are structures shown in FIGS. 1 and 2.
A centrifugal casting apparatus was prepared in which eight molds having mold spaces of the same shape as the slider plates shown in Fig. 1 were evenly arranged, and each mold was in communication with the sprue through a radial hot water passage.

While this apparatus was being rotated around the sprue, the SiC particle-dispersed ADC10 alloy molten metal obtained in the same manner as in Example 1 was injected through the sprue, and the molten metal was solidified under the action of centrifugal force. After demolding, unnecessary solidified parts on the sprue side were removed, T6 treatment was performed, and the sliding surface was lightly cut and holes were bored. As a result, it was possible to manufacture a slider plate 1 made of a composite material of SiC particles and ADC10 alloy and having the shape shown in FIGS. 1 and 2.

Example 4 SiC particles with an average particle size of 20 μm and an average particle size of 30 μm
B4C particles of A403 heated to 750 °C
The particles were added little by little to the molten A4032 alloy with stirring while stirring to obtain a molten A4032 alloy in which the total amount added was 20% (10% SiC particles, 10% B4 C particles) in terms of volume percentage.

This molten metal was continuously cast while stirring to produce a billet with an outer diameter of 6 inches. This billet was extruded using a die having a rectangular hole with a width equivalent to that of the slider plate to be manufactured and a thickness equal to the thickness of the slider plate to be manufactured plus a cutting allowance of 0.6 mm. After cutting the obtained extruded material into the shapes shown in FIGS. 5 and 6, it was subjected to T6 treatment,
The sliding surface side was cut to a thickness of approximately 0.6 mm, and a hole was further drilled. As a result, the slider plate 1 having the shape shown in FIGS. 5 and 6 could be manufactured.

Example 5 SiC particles and A6061 alloy powder were uniformly mixed by stirring in water, and then water was evaporated to obtain a mixed powder containing 20% by volume of SiC particles in A6061 alloy powder. . This mixed powder was filled into an aluminum can with an outer diameter of 170 mmφ, the inside of the can was evacuated through an exhaust pipe connected to the lid of the can, and the exhaust pipe was sealed by forge welding. This can filled with mixed powder was compressed at room temperature to increase the packing density, and then hot pressed into a cylindrical shape.

The outer peripheral surface and both end surfaces of this hot-pressed material were cut to produce an extruded billet having an outer diameter of 150 mm and entirely made of composite material. This billet was extruded into a square bar shape, and the resulting square bar was cut to obtain a forging material, which was then forged in a die having a cavity of the same shape as the slider plate 1 of FIGS. 3 and 4. Thereafter, the forged product was subjected to T6 treatment, and the sliding surface was lightly cut and bored. As a result, it was possible to manufacture a slider plate 1 made of A6061 alloy reinforced with 20% SiC particles and having the shape shown in FIGS. 3 and 4.

[0029]

[Effects of the Invention] As explained above, according to the present invention, it is possible to easily manufacture a slider plate made of a composite material of aluminum or aluminum alloy reinforced with ceramic particles, and a remarkable industrial effect can be obtained. It will be done.

[Brief explanation of drawings]

FIG. 1 is a plan view of a slider manufactured according to an embodiment of the present invention.

[Fig. 2] A front view of the slider plate in Fig. 1.

FIG. 3 is a plan view of a slider manufactured according to another embodiment of the present invention.

FIG. 4 is a front view of the slider shown in FIG. 3.

FIG. 5 is a plan view of a slider manufactured according to still another embodiment of the present invention.

[Fig. 6] A front view of the slider plate in Fig. 5.

FIG. 7 is a sectional view showing an example of a split mold used in the manufacturing method of the present invention.

[Explanation of symbols]

1: Slide plate 2: Split mold 2A: Fixed mold 2B: Movable mold 3: Core pin 4: Knockout pin 5
: Molten metal inlet

Claims (6)

[Claims] Claim 1: While stirring aluminum or aluminum alloy molten metal, ceramic particles are mixed into it and dispersed uniformly, and then the ceramic particle-dispersed molten metal is shaped into a slider plate (with cutting or grinding allowance taken into account). include)
1. A method for producing a contact plate for a current collector, the method comprising molding it into a mold. [Claim 2] Mold forming is performed by clamping a split mold having a slider-shaped cavity at a predetermined pressure, then injecting a molten metal with dispersed ceramic particles therein, and solidifying it under pressure. A method for manufacturing a contact plate for a current collector according to claim 1. 3. The method for manufacturing a contact plate for a current collector according to claim 1, wherein the molding is carried out by injecting a molten metal in which ceramic particles are dispersed into a mold having a contact plate-shaped cavity and solidifying the melt. . 4. Mold forming has a sprue at the center, and a plurality of slider-shaped mold spaces are evenly arranged around this sprue, and these mold spaces communicate with the sprue through radial hot water passages. Claim 1, characterized in that the process is carried out by using a centrifugal casting device with a sprue, injecting ceramic particle dispersed molten metal from the sprue while rotating the centrifugal casting device around the sprue, and solidifying the molten metal under centrifugal force. The method for manufacturing the slider plate for a current collector described above. 5. While stirring the molten aluminum or aluminum alloy, ceramic particles are mixed into the molten metal and dispersed uniformly, and then the ceramic particle dispersed molten metal is solidified to produce a composite material ingot. 1. A method of manufacturing a contact plate for a current collector, which comprises plastically working a contact plate into a contact plate shape. 6. A current collector characterized in that ceramic particles and aluminum powder or aluminum alloy powder are mixed and dispersed uniformly, deaerated and solidified, and then plastic processed into a predetermined contact plate shape. A method for manufacturing a slider for equipment.