JPH06100962A - Electrical contact material - Google Patents

Abstract

PURPOSE:To improve the mechanical strength and welding resistance of an electrical contact material without deteriorating its workability or the like and to expand the range of the using electric current by forming an Ag MeO contact material in which Cd, Sn, Sb or the like are contained in Ag and Ag-Fe powder into combined wire rod. CONSTITUTION:This electrical contact material is formed by extruding a bar material constituted of a combined material of an Ag-MeO contact material and Ag-Fe powder. The same contact material contains one or more kinds selected from, by weight, 0.05 to 15% Cd, Sn, Sb, Zn, In, Bi and Te in Ag, and the same Ag-Fe powder contains 0.01 to 20% Fe. Then, the electrical contact material is constituted of combined wire rod or bar stock, and the same Ag-MeO contact material occupies 5 to 65% area ratio (to the sectional area of the whole body).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite electric contact material which is superior in welding resistance and wear resistance to Ag-Fe alloys and has the same workability and spot weldability.

[0002]

2. Description of the Related Art Conventionally, various materials have been used as electric contact materials, but especially Ag-Fe contacts are widely used in place of Ag because of their low contact resistance and low consumption. In addition, since Ag-Fe is easy to process and spot weld, it is possible to automate the work of sticking to a base material, etc., resulting in low assembly costs and stable quality.

[0003]

[Problems to be Solved by the Invention] However, Ag-Fe
Has a problem that its mechanical strength is small and its welding resistance is inferior to that of Ag-oxide systems such as Ag-CdO, so that its use range is limited to a relatively small current region. In recent years, various devices and equipment have been aiming for weight reduction, downsizing, and large capacity, but also from this point, there is a problem that the Ag-Fe-based welding resistance is poor.

As a method for solving these problems, Ag-
We are trying to improve the characteristics by adding various metallic elements to the Fe alloy. Ag-Fe alloys are manufactured by powder sintering because there is almost no solid solubility between Ag and Fe, but the above-mentioned attempts have not yet reduced the effect of arc heat generated during opening and closing. The stable contact characteristics, which are the original characteristics of the Fe alloy, are impaired, and the welding resistance is reduced due to temperature rises.

Further, the workability and spot weldability, which are the characteristics of Ag-Fe alloys, are hindered by the mixture of various additives.
There is also a problem that the automation line cannot be assembled. Therefore, an experiment was conducted based on the idea that the various phenomena of oxides against arc, such as the contact surface cleaning action and the arc extinguishing action, are most closely related to the properties of the added oxide, especially the vapor pressure temperature characteristics. As a result of repeating, Cd, Sn, Sb, Zn, In, Bi, Te
By adding at least one kind of each oxide of
It has been found that there is a great effect in improving the mechanical strength and the welding resistance without deteriorating the workability and spot weldability, which are the characteristics of Ag-Fe, and expanding the operating current range.

[0006]

SUMMARY OF THE INVENTION Therefore, the present invention is
At least one of Cd, Sn, Sb, Zn, In, Bi, Te is 0.05
~ 15Wt% Ag-MeO based contact material with Fe content of 0.01
〜20Wt% is mixed with Ag-Fe powder to form a bar, and this bar is extruded to form a composite wire and strip, and
The feature is that the Ag-MeO-based contact material occupies an area ratio of 5 to 65% of the entire cross-sectional area.

By doing so, the influence of arc heat generated at the time of opening and closing as an electrical contact is reduced. Note that the upper limit of addition of Ag-MeO-based contact material is 15 Wt.
The reason why the content is set to% is that if it is added in excess of that, it becomes very brittle and reduces the good workability, which is the original feature of Ag-Fe, and at the same time, the welding resistance is impaired due to temperature rise. Is. In addition, the lower limit of 0.05 Wt% is the minimum effect.

If the area ratio of the Ag-MeO-based contact material occupying the entire cross-sectional area is less than 5%, the amount of the Ag-MeO-based contact material is too small, which causes a problem in the contact resistance, particularly in the welding resistance. The area ratio is over 65%.
This is because problems arise in the original features of good workability and spot weldability.

[0009]

EXAMPLES Examples of the present invention will be described below.

[0010]

[Table 1]

Table 1 shows examples of the present invention, in which Cd, S
An alloy containing at least one of n, Sb, Zn, In, Bi, Te is internally oxidized as powder by an atomizing device, and it is extruded after forming / sintering.
mm pieces and a height of 300 mm are placed in a mold having the area ratios shown in Examples 1 to 10, and Ag powder and Fe powder having a size of 300 mesh or less are mixed in the gap using a V-type mixer. The powder thus obtained was compressed and filled, molded at 3 t / cm ² , and then sintered at 800 ° C. in an inert atmosphere to obtain a bar material as shown in FIG.

This rod was heated to 800 ° C. in an inert atmosphere and then extruded into a wire having a diameter of 10φ as shown in FIG. This wire rod was repeatedly annealed and drawn in an inert atmosphere to form a wire rod having a diameter of 6φ, and header processing was performed to obtain a rivet-shaped contact material having a diameter of 6φ. The rivet-shaped contact material produced as described above was replaced with an ASTM tester (AC100V, 40
The contact resistance and the number of welding were measured using A). The results are shown in Table 2.

[0013]

[Table 2]

[0014]

According to the present invention described in detail above, Ag
Ag-MeO-based material containing at least one of Cd, Sn, Sb, Zn, In, Bi, and Te, and Ag-Fe powder are mixed to form a rod, and the rod is extruded to form a composite wire rod. And strips, and
The Ag-MeO-based contact material occupies an area ratio of 5 to 65% of the overall cross-sectional area, which improves mechanical strength without degrading the workability and spot weldability that are the characteristics of Ag-Fe. Therefore, the welding resistance can be improved and the current range used can be expanded.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a bar material.

FIG. 2 is an explanatory diagram of a wire rod.

Claims (1)

[Claims] 1. An Ag-MeO-based contact material containing 0.05 to 15 Wt% of at least one of Cd, Sn, Sb, Zn, In, Bi, and Te in Ag, and an Fe content of 0.01 to 20 Wt. % Of Ag-Fe powder to form a bar, and this bar is extruded to form a composite wire and strip, and the Ag-MeO contact material has an area ratio of 5 to 65% of the total cross-sectional area. Electrical contact material characterized by occupying.