JP2001202841A - Ag-CARBON CONTACT MATERIAL AND METHOD OF MANUFACTURING THE SAME - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve problems in Ag-carbon contact material that has weak consumption resistant property and can scarcely stand elongation processing of wire rod or plastic processing due to material characteristic thereof, in which fine cracks are generated in the contact inside in the case that it is used for electromagnetic switch as contact property, and peelings are generated on boundary of Ag layer required in jointing with a support member and contact member, and excess consumption is caused. SOLUTION: An outer periphery is Ag, a contact surface is Ag-carbon and a surface opposing to it is Ag, Ag of Ag-carbon at its inside is disposed parallel to a direction perpendicular to the contact surface.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an Ag or Ag alloy (referred to as "Ag-based" in the present invention) -carbon-based contact material used for an electromagnetic switch and the like, and a method for producing the same.

[0002]

2. Description of the Related Art As a contact material conventionally used for an electromagnetic switch and the like, there is an Ag-carbon contact material. this is,
It is widely used due to its excellent contact resistance and low contact resistance.

[0003]

However, such an Ag-carbon contact material has a problem of inferior wear resistance, and is fragile due to its material properties, and is extremely difficult to plastically process. However, there is a problem that it is practically impossible to increase the length of the workpiece. Furthermore, as a contact characteristic, when used in an electromagnetic switch or the like, minute cracks are generated inside the contact due to expansion and contraction caused by arc heat generated at the time of opening and closing, and furthermore, an Ag layer required for joining with the base material There is a problem that peeling occurs at a boundary surface between the contact member and the contact material portion, thereby causing excessive contact wear.

[0004]

SUMMARY OF THE INVENTION Accordingly, the present invention is to improve the material characteristics by forming Ag or a layer rich in Ag on the outer peripheral surface other than the contact surface. Ag-carbon system, the opposite surface is Ag, and the Ag-carbon system Ag inside is arranged side by side in the direction orthogonal to the contact surface, and more specifically, the carbon-based material is Gr, Gr is 0.2 to 6%, and the balance is Ag or an Ag alloy.

Further, as a method for producing the same, Ag powder and carbon powder are stirred and mixed, and the mixed powder is filled into an Ag pipe and pressurized to form a composite billet, and the composite billet is extruded to a predetermined diameter by a hot rolling mill. Then, the rod is formed into a rod having a predetermined diameter by drawing, and the Ag powder is stretched. The rod is cut to a predetermined thickness in a radial direction to form a disk, and one side of the disk is in close contact with the disk. Ag on the ceramic plate by heating in air and decarburizing the surface
The surface is Ag-carbon, and the periphery is Ag.

Further, as another production method, Ag powder, carbon powder and added metal powder are stirred and mixed, and the mixed powder is pressed and molded to form a billet having a predetermined diameter. Extrusion is performed by extruding to form a rod having a predetermined diameter, and at the same time, Ag powder is stretched, and the rod is heated in the atmosphere to perform a decarburization process on the periphery to form an Ag surface.
Next, a rod having a desired diameter is formed by a drawing process, and the material of the rod is cut into a predetermined thickness in a radial direction to form a disk, and the disk is arranged on a ceramic plate in a state in which one surface of the disk is in close contact with the disk. By heating in the air to perform decarburization of the peripheral surface and the surface, the peripheral surface is an Ag-rich layer containing the additive metal, one surface is an Ag-rich layer containing the additive metal, and the opposite surface is Ag-carbon-
It is an additive metal.

Here, the reason why the lower limit of Gr is set to 0.2% is that if it is less than this, the contact characteristics of the Ag-carbon contact deteriorate, and the reason that the upper limit is 6% is weak. It is because. In addition, the amount of each additional metal is 0.2
The reason for setting it to ６6% is that if both the lower limit and the upper limit exceed the above range, the contact characteristics of the Ag-carbon contact deteriorate.

[0008]

Embodiments of the present invention will be described below. First Embodiment Example 4 750 g of 325-mesh Ag powder, 250 g of graphite powder as carbon powder, and a total amount of 5,000 g were stirred and mixed with a V mill, and this mixed powder (Ag-5% Gr) 1 was added to a thickness of 5%.
An Ag pipe 2 having an outer diameter of 60 mm and an outer diameter of 60 mm was filled and pressed to produce a composite billet 3.

Next, the composite billet was extruded to a diameter of 6 mm by a hot extruder, and a rod-shaped composite wire having a diameter of 5 mm was obtained by drawing. Thereby, as shown in FIG. 2, Ag in the mixed powder is elongated in the longitudinal direction. Next, the composite wire was radially cut into a thickness of 2 mm to obtain a disc. As a result, Ag is arranged in a columnar shape in the thickness direction of the disk, and as shown in FIG. 3, Ag is arranged on the surface in a dotted manner on the cut surface.

Next, the disk is placed on a ceramic plate 4 made of alumina or the like in a state where one side thereof is in close contact with the disk, and the disk
A decarburization treatment was performed by heating at 30 ° C. for 30 minutes to oxidize the carbon-based Gr on the outer surface to obtain a disk having Ag on the periphery, Ag on one side, and Ag-Gr on the opposite side. From this disk, a contact piece 5 as shown in FIG. 5 was obtained. The contact piece was subjected to a contact test after acid treatment. Table 1 shows the results.

Second Embodiment Ag-3% Gr-3% W in the same manner as in the above embodiment.
Ag powder 2 having a thickness of 5 mm and an outer diameter of 60 mm
To form a composite billet 3. Next,
This composite billet was extruded to a diameter of 6 mm by a hot extruder, and a rod-shaped composite wire having a diameter of 5 mm was obtained by drawing. Thereby, as shown in FIG. 2, Ag in the mixed powder is elongated in the longitudinal direction.

Next, the composite wire was radially cut into a thickness of 2 mm to form a disk. As a result, Ag is arranged in a columnar shape in the thickness direction of the disk, and as shown in FIG. 3, Ag is arranged on the surface in a dotted manner on the cut surface. Next, the disc was placed on a ceramic plate 4 made of alumina or the like in a state in which one side of the disc was in close contact with the disc and heated at 700 ° C. for 30 minutes in the atmosphere to oxidize the carbon-based Gr on the outer surface. A disk having Ag on the peripheral surface, Ag-W on one surface, and Ag-Gr-W on the opposite surface was obtained.

The contact piece 5 shown in FIG.
I got The contact piece was subjected to a contact test after acid treatment. Table 1 shows the results. Third Embodiment In the same manner as in the above embodiment, Ag-1.5% Gr-
A mixed billet 3 of 1.5% W-2% WC (tungsten carbide) was filled and pressed into an Ag pipe 2 having a thickness of 5 mm and an outer diameter of 60 mm.

Next, the composite billet was extruded with a hot extruder to a diameter of 6 mm, and a rod-shaped composite wire having a diameter of 5 mm was obtained by drawing. Thereby, as shown in FIG. 2, Ag in the mixed powder is elongated in the longitudinal direction. Next, the composite wire was radially cut into a thickness of 2 mm to obtain a disc. As a result, Ag is arranged in a columnar shape in the thickness direction of the disk, and as shown in FIG. 3, Ag is arranged on the surface in a dotted manner on the cut surface.

Next, this disk is placed on a ceramic plate 4 of alumina or the like in a state in which one side is in close contact with the disk, and the disk
C. for 30 minutes to perform decarburization treatment to oxidize the carbon-based Gr on the outer surface, and the peripheral surface is Ag and one surface is Ag-W-
WC, a disk whose face was Ag-Gr-W-WC was obtained.
From this disk, a contact piece 5 as shown in FIG. 5 was obtained. The contact piece was subjected to a contact test after acid treatment. Table 1 shows the results.

Fourth Embodiment Ag-2.0% Gr-5 in the same manner as in the above embodiment.
% Ni-0.5% Fe mixed powder 1 having a thickness of 5 mm and an outer diameter of 6
Filling and pressurizing a 0 mm Ag pipe 2 to form a composite billet 3
Was prepared. Next, this composite billet was extruded with a hot extruder to a diameter of 6 mm, and a rod-shaped composite wire having a diameter of 5 mm was obtained by drawing. Thereby, as shown in FIG. 2, Ag in the mixed powder is elongated in the longitudinal direction.

Next, the composite wire was radially cut into a thickness of 2 mm to obtain a disc. As a result, Ag is arranged in a columnar shape in the thickness direction of the disk, and as shown in FIG. 3, Ag is arranged on the surface in a dotted manner on the cut surface. Next, the disc was placed on a ceramic plate 4 made of alumina or the like in a state in which one side of the disc was in close contact with the disc and heated at 700 ° C. for 30 minutes in the atmosphere to oxidize the carbon-based Gr on the outer surface. The peripheral surface is Ag, one surface is Ag-Ni-Fe, and the opposite surface is Ag-Gr.
-A disk of Ni-Fe was obtained.

The contact piece 5 as shown in FIG.
I got The contact piece was subjected to a contact test after acid treatment. Table 1 shows the results. Fifth Embodiment In the same manner as in the above embodiment, Ag-4.5% Gr-
0.5% W-1% Ni mixed powder 1 is 5 mm in thickness and 6 mm in outer diameter.
Filling and pressurizing a 0 mm Ag pipe 2 to form a composite billet 3
Was prepared.

Next, the composite billet was extruded with a hot extruder to a diameter of 6 mm, and a rod-shaped composite wire having a diameter of 5 mm was obtained by drawing. Thereby, as shown in FIG. 2, Ag in the mixed powder is elongated in the longitudinal direction. Next, the composite wire was radially cut into a thickness of 2 mm to obtain a disc. As a result, Ag is arranged in a columnar shape in the thickness direction of the disk, and as shown in FIG. 3, Ag is arranged on the surface in a dotted manner on the cut surface.

Next, this disk is placed on a ceramic plate 4 made of alumina or the like in a state in which one side of the disk is in close contact with the ceramic plate 4 in the atmosphere.
C. for 30 minutes to perform decarburization treatment to oxidize the carbon-based Gr on the outer surface, and the peripheral surface is Ag and one surface is Ag-W-
A disk of Ni and the opposite surface of Ag-Gr-W-Ni was obtained.
From this disk, a contact piece 5 as shown in FIG. 5 was obtained. The contact piece was subjected to a contact test after acid treatment. Table 1 shows the results.

Sixth Embodiment Ag-0.5% Gr-4 in the same manner as in the above embodiment.
% WC-0.5% Ni mixed powder 1 having a thickness of 5 mm and an outer diameter of 6
Filling and pressurizing a 0 mm Ag pipe 2 to form a composite billet 3
Was prepared. Next, this composite billet was extruded with a hot extruder to a diameter of 6 mm, and a rod-shaped composite wire having a diameter of 5 mm was obtained by drawing. Thereby, as shown in FIG. 2, Ag in the mixed powder is elongated in the longitudinal direction.

Next, the composite wire was radially cut to a thickness of 2 mm to obtain a disc. As a result, Ag is arranged in a columnar shape in the thickness direction of the disk, and as shown in FIG. 3, Ag is arranged on the surface in a dotted manner on the cut surface. Next, the disc was placed on a ceramic plate 4 made of alumina or the like in a state in which one side of the disc was in close contact with the disc and heated at 700 ° C. for 30 minutes in the atmosphere to oxidize the carbon-based Gr on the outer surface. The peripheral surface is Ag, one surface is Ag-WC-Ni, and the opposite surface is Ag-Gr
A disk of -WC-Ni was obtained.

The contact piece 5 as shown in FIG.
I got The contact piece was subjected to a contact test after acid treatment. Table 1 shows the results. Seventh Embodiment Ag powder of 325 mesh is 4790 g, graphite powder is 200 g of carbon powder, Ni powder is 10 g, and total amount is 5000 g.
(Ag-4% Gr-0.2% Ni) was stirred and mixed with a V mill, and the mixed powder was pressed and formed into a billet having a diameter of 80 mm × L.

Next, the billet is extruded into a rod having a diameter of 10 mm by a hot extruder, whereby Ag in the mixed powder is elongated in the longitudinal direction. Next, the rod-shaped body is heated at 700 ° C. for 45 minutes in the atmosphere to perform a decarburization treatment to oxidize the carbon-based Gr on the outer surface, and the peripheral surface is made of Ag.
−Ni. 10mm diameter by drawing
And the Ag is also elongated.

This rod was cut radially into a thickness of 2 mm to form a disk. As a result, Ag is arranged in a columnar shape in the thickness direction of the disk, and Ag is arranged on the surface in a dotted manner on the cut surface. Next, this disc is placed on a ceramic plate such as alumina in a state in which one side is in close contact with the disc, and heated at 700 ° C. for 30 minutes in the air to perform a decarburization treatment to oxidize the carbon-based Gr on the surface. Is Ag-Ni, one side is Ag-N
i, a disk whose face was Ag-Gr-Ni was obtained.

The contact piece 5 as shown in FIG.
I got The contact piece was subjected to a contact test after acid treatment. Table 1 shows the results. In addition, A used in the above embodiment
The g pipe is not necessarily Ag, for example, W, WC,
An Ag alloy pipe containing at least one or more of Ni, Fe and other various metals may be used.

A contact piece according to the prior art is shown as a comparative example. Conventional Example 1 4750 g of 325 mesh Ag powder, 250 g of graphite powder, and a total amount of 5000 g were stirred and mixed with a V mill,
This mixed powder (Ag-5% Gr) is pressed and molded into a billet having an outer diameter of 60 mm, and is then 6 mm thick and 30 m wide by a hot extruder.
It was extruded into a shape of m.

Next, a 0.3 mm thick, 30 mm wide A
The g plate was pressed with the Ag-Gr material by a hot rolling mill and adjusted and rolled to a thickness of 2 mm to obtain a clad plate with Ag. Next, the clad plate was press-punched into a disk shape having a diameter of 5 mm to obtain a contact piece. The contact piece was subjected to a contact test after acid treatment. Table 1 shows the results. Conventional Example 2 A mixed powder of Ag-3% Gr-3% W was extruded into a shape having a thickness of 6 mm and a width of 30 mm in the same processing procedure as in the above conventional example.

Next, A having a thickness of 0.3 mm and a width of 30 mm
The g plate was pressed with the Ag-3% Gr-3% W material by a hot rolling mill, and adjusted and rolled to a thickness of 2 mm to obtain a clad plate with Ag. Next, the clad plate was press-punched into a disk shape having a diameter of 5 mm to obtain a contact piece. The contact piece was subjected to a contact test after acid treatment. Table 1 shows the results.

Conventional Example 3 A mixed powder of Ag-1.5% Gr-1.5% W-2% WC was processed in the same processing procedure as in the above-mentioned conventional example to a thickness of 6 mm and a width of 30 m.
It was extruded into a shape of m. Next, thickness 0.3m
Ag, 30 mm in width Ag plate with the above Ag-1.5% Gr-
A 1.5% W-2% WC material was pressed with a hot rolling mill and adjusted to a thickness of 2 mm to obtain a clad plate with Ag.

Next, the clad plate was stamped out into a disk shape having a diameter of 5 mm to obtain a contact piece. The contact piece was subjected to a contact test after acid treatment. Table 1 shows the results. The contact pieces of the embodiment and the comparative example were assembled in an electromagnetic switch, and a mechanical opening / closing test was performed in a non-energized state, and the workability was compared based on the presence or absence of cracks on the contact surface.

Next, the contact piece of the embodiment was newly incorporated in an electromagnetic switch, and a contact opening / closing test was performed under the conditions of 200 V AC, 50 A (resistive load), contact pressure 500 g, and separation pressure 700 g. The contact piece of the conventional example is newly incorporated in the electromagnetic switch in the same manner as in the present embodiment, and the AC200 is used.
V, 50A (resistance load), contact pressure 500g, separation pressure 70
A contact switching test was performed under the condition of 0 g.

[0033]

[Table 1]

The shape of the contact piece shown in each of the above-described embodiments and the conventional example is a disk shape, but is not limited to this shape. For example, as shown in FIGS. And any other desired shape.

[0035]

According to the present invention described in detail above, it is apparent from the test results that the wear resistance is improved as compared with the prior art. This is the internal Ag
The powder is elongated in the processing step to form a fibrous matrix in the longitudinal direction, and the contact piece is formed by cutting it in the radial direction, thereby significantly improving arc resistance, welding resistance, and wear resistance. That's why.

Furthermore, by protecting and restraining the Ag-C contact material with Ag or an Ag-rich layer formed on the outer periphery of the contact piece, the contact material is abnormally scattered by an arc or spark generated when the contact is opened or closed. -It is because the consumption is improved. Ag or A formed on the outer periphery
Due to the effect of the layer rich in g, processing into wire shape and the like becomes easy, so that generation of surface defects in the processing process can be suppressed, product accuracy is extremely improved, and the degree of material processing is further improved. And the carbon in Ag has a high dispersibility, and has an effect of increasing the density and improving the contact characteristics.

In addition to the above effects, there is an effect that the contact material has excellent workability without adversely affecting the contact characteristics such as welding resistance.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a billet.

FIG. 2 is an explanatory diagram showing an Ag matrix.

FIG. 3 is an explanatory view showing an example of the shape of a disk.

FIG. 4 is an explanatory view of a decarburization step.

FIG. 5 is an explanatory view showing an example of the shape of a contact piece;

FIG. 6 is an explanatory view showing an example of the shape of a contact piece.

FIG. 7 is an explanatory view showing an example of the shape of a contact piece;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Mixed powder 2 Pipe 3 Composite billet 4 Ceramic plate 5 Contact piece

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4K018 AA02 AB07 AC01 BA01 CA50 EA34 EA52 FA06 FA09 HA03 JA27 KA34 KA62 4K020 AA24 AC05 BB29 BC02 BC03 5G023 AA03 AA20 BA11 CA02 CA50 5G050 AA01 AA07 AA14 EA05

Claims (13)

[Claims] In an Ag-carbon contact material, the outer peripheral surface is Ag, the contact surface is Ag-carbon, and the opposite surface is Ag.
Wherein Ag-carbon-based Ag inside is arranged side by side in a direction perpendicular to the contact surface. 2. The Ag-carbon contact material according to claim 1, wherein the outer peripheral surface is made of an Ag alloy. 3. The method according to claim 1, wherein the contact surface is Ag.
Ag-carbon contact material characterized in that the metal layer is rich in iron. 4. The Ag-carbon-based contact material according to claim 1, wherein the Ag-carbon-based carbon-based material is Gr, Gr is 0.2 to 6%, and the balance is Ag. 5. The method according to claim 1, wherein the Ag-carbon-based carbon-based material is Gr, and Gr is 0.2 to 6%.
An Ag-carbon contact material, wherein at least one of C is 0.2 to 6% and the balance is Ag. 6. The method according to claim 1, wherein the Ag-carbon based carbon-based material is Gr, 0.2 to 6% of Gr, Ni,
An Ag-carbon contact material, characterized in that at least one of Fe is 0.2 to 6% and the balance is Ag. 7. The method according to claim 1, wherein the Ag-carbon-based carbon-based material is Gr, and the content of Gr is 0.2 to 6%.
An Ag-carbon contact material characterized in that at least one of C, Ni and Fe is 0.2 to 6% and the balance is Ag. 8. Ag powder and carbon powder are stirred and mixed, and the mixed powder is filled in an Ag pipe and pressurized to form a composite billet.
The composite billet is extruded to a predetermined diameter by a hot rolling mill, formed into a rod having a predetermined diameter by drawing, and Ag powder is stretched, and the rod is cut into a predetermined thickness in a radial direction to form a circle. A plate is formed, and one side of the disk is placed on a ceramic plate in a state of being in close contact with the ceramic plate and heated in the air to decarburize the surface to form an Ag surface.
A method for producing an Ag-carbon contact material, wherein carbon and its surroundings are Ag. 9. The method for producing an Ag-carbon contact material according to claim 8, wherein the Ag powder is a mixed powder obtained by mixing an Ag powder with an additive metal powder. 10. The method according to claim 8, wherein the pipe is an Ag alloy pipe. 11. Ag powder and carbon powder are stirred and mixed, and the mixed powder is pressed and molded to form a billet having a predetermined diameter, and the billet is extruded by a hot extruder and extruded to a predetermined billet. While forming into a rod having a diameter, the Ag powder is stretched, and the rod is heated in the air to perform a decarburization process on the surroundings to obtain an Ag surface. The rod-shaped material is cut to a predetermined thickness in the radial direction to form a disc, and the disc is arranged on a ceramic plate in a state where one side of the disc is in close contact with the disc and heated in the atmosphere to form a disc. And a method for producing an Ag-carbon contact material, wherein the surface is decarburized and the peripheral surface is Ag, one surface is Ag, and the opposite surface is Ag-carbon. 12. The method for producing an Ag-carbon contact material according to claim 8, wherein the mixed powder is Ag powder-carbon powder-added metal powder. 13. The method for producing an Ag-carbon contact material according to claim 8, wherein the carbon powder is a Gr powder.