JP2884535B2 - Composite materials for electrical contacts - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention uses an Ag-oxide-based material as a core material,
The present invention relates to a composite material for an electrical contact using an Ag-oxide system having an Ag alloy layer formed thereon.

[Conventional technology]

Conventionally, Ag, Ag-Ni or Ag
A so-called Ag-oxide-based material in which an oxide such as Cd, Sb, Sn, Te, and In is dispersed is used.

Among them, Ag-oxide based contact materials are known to be excellent in welding resistance, wear resistance and the like, and are known to be used in a wide range, but they have problems in workability and adhesion bonding to a base material.

That is, Cd, Sb, Sn, Te, In
And the like, the bonding strength by spot welding or brazing is significantly lower than that of non-oxide-based materials.

Therefore, a material has been considered in which an Ag-oxide-based material is used as a base material and an Ag layer that enables spot welding or brazing is formed on a joint with the base material or on the outer periphery of the base material.

In recent years, rationalization and automation of mechanical devices in various industrial fields have been remarkably developed, but with this trend, devices are becoming larger and more complex, but these control systems are rather smaller, High frequency operation and large capacity are required.

In addition, with the frequent operation of the equipment, the contact surface of the control switch is heated to a high enough temperature to melt locally during operation due to arc heat and Joule heat accompanying opening and closing, and drops to room temperature when stopped. Therefore, the high-temperature and low-temperature thermal cycles are repeated.

[Problems to be solved by the invention]

When using the Ag-oxide based contact material under such circumstances, frequent expansion and contraction will be repeated, complex stress will be intensively applied inside the contact, and the contact surface will be concave. Since an arcuate curved deformation occurs, the Ag layer provided to enable spot welding and brazing receives a strong stress that peels off at the interface with the contact base material or the base material.

This causes many problems in the bonding strength between the contact base material and the base material in combination with the low mechanical strength of Ag itself. That is, while the contact performance of the Ag-oxide-based material cannot be sufficiently exhibited during use, a phenomenon such as separation of the contact base material and Ag or the base material occurs, which causes abnormal wear. These improvements are desired.

[Means for solving the problem]

The present invention relates to a method for producing 0.05 to 6 wt% of Sb oxide in Ag,
~ 2 wt% Te oxide and 0.05-5 wt% Sn, In, Cu, Mn
The core material is a material in which each oxide of
Ag alloy layer formed by adding at least two of the elements Sb, Te, Sn, In, Cu, and Mn in Ag in the range of 0.01 to 2 wt%, and occupying the entire cross-sectional area of the composite material The area ratio of the Ag alloy layer is 5 to 40%.

Also, 0.05 to 6 wt% of Sb oxide in Ag and 0.01 to 2 wt%
% Te oxide and 0.05 to 5 wt% of Sn, In, Cu, Mn oxides and a material in which one or both of Fe and Ni oxides are dispersed at 0.01 to 1 wt% as a core material; An Ag alloy layer formed by adding at least two of the elements Sb, Te, Sn, In, Cu, and Mn in Ag in a range of 0.01 to 2 wt% is formed on the outer periphery thereof.
The area ratio of the Ag alloy layer to the entire cross-sectional area of the composite material is 5 to 40%.

In the above, the amount of Sb oxide to be dispersed in Ag is 0.
The reason for limiting the amount to 05 to 6 wt% is that if it is less than 0.05 wt%, a cleaning effect due to the arc generated at the time of opening and closing cannot be expected, and if it exceeds 6 wt%, the amount of scattered consumption by the arc may rather increase. .

The reason for limiting the amount of Te oxide to 0.01 to 2 wt% is that
If the content is less than 0.01 wt%, the improvement in welding resistance due to the addition of Te oxide cannot be expected. If the content exceeds 2 wt%, the workability is remarkably reduced, and mass productivity when processing as a contact becomes a problem. .

Further, the lower limit of the amount of oxides of Sn, In, Cu, Mn is 0.05 wt.
The reason why the amount is limited to% is that if the addition is less than this, a synergistic addition effect with Te cannot be expected, and if the addition exceeds 5% by weight, the contact characteristics, particularly the contact stability, deteriorate.

In addition, the addition of Fe and Ni has no effect of refining the crystal grains when the addition is less than 0.01 wt%, and the addition of more than 1 wt% has a large effect on other characteristics such as an increase in electric resistance.

On the other hand, for the Ag alloy formed on the outer periphery of the contact base material, Sb,
The reason why the range of adding two or more of the elements of Te, Sn, In, Cu, and Mn is limited to 0.01 to 2 wt% is that if the amount of the added element is less than 0.01 wt%, the mechanical strength is improved. And elemental Ag
This is because the effect of diffusion into the matrix is thin, and an increase in composite strength cannot be expected. Addition of more than 2 wt% reduces workability and reduces the effect of coating and protection. This is because, depending on the heating atmosphere at the time, scale may be formed on the surface to make the compounding difficult.

If the ratio of the Ag alloy layer to the cross section of the composite wire or strip is less than 5%, the effect of coating the contact base material will be small, and spot welding or brazing to the base material will be difficult. This is because the amount of the material is too large, which causes a problem particularly in the welding resistance among the contact characteristics.

〔Example〕

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

First Example Ag- (5.5Sb-0.05Te-0.1Sn-3In-2Cu- 13 mm in diameter
0.1Mn-0.15Ni) O _x to the wire of each wt%, a thickness of 1.5mm produced by drawing Ag-0.2Sb-0.1Te-0.2Sn- 0.2I
n-0.2Cu-0.1Mn each wt% pipe is fitted and tightly contacted, 700 ℃
And composited by drawing.

The wire was heated at 650 ° C. for 4 hours in an inert atmosphere to mutually diffuse the core material and the outer peripheral material.

This was repeated annealing and drawing in an inert atmosphere to obtain a wire having a diameter of 3 mm.

Second Example Ag- (2Sb-1.5Te-0.1Sn-4In-1Cu-0.1 having a diameter of 13 mm
The 5Mn-0.2Fe-0.35Ni) O _x each wt% of the wire, Ag-0.1Sb-0.05Te-0.5In- 1mm thick was prepared by drawing
A pipe of 0.1Cu-0.05Mn each wt% was fitted and adhered to each other, heated to 700 ° C, and combined by drawing.

The wire was heated at 650 ° C. for 4 hours in an inert atmosphere to mutually diffuse the core material and the outer peripheral material. This was repeated annealing and drawing in an inert atmosphere to obtain a wire having a diameter of 3 mm.

Further, third to sixth examples shown in the following table were produced in substantially the same manner as in the first and second examples.

After cutting each wire rod of each of the above examples to a length of 2.5 mm,
Spot welding to the base material, measuring the shear joint strength and incorporating it into a commercially available contactor, voltage 220V, current 78A,
A mounting test was performed with a power factor of 0.35, and is shown in the table below.

In addition, the result by the following prior art is shown for comparison.

First Conventional Example A 1 mm thick Ag pipe made by drawing was fitted and tightly attached to a 13 mm diameter Ag-12 wt% CdO wire,
The mixture was heated to ℃ and composited by drawing.

Annealing and drawing of this wire are repeated to create a diameter of 3 mm.
Was obtained.

Second conventional example A 0.5 mm thick Ag pipe made by drawing was fitted and tightly attached to a 13 mm diameter Ag-10 wt% CdO wire,
The mixture was heated to ℃ and composited by drawing.

Annealing and drawing of this wire are repeated to create a diameter of 3 mm.
Was obtained.

From this test, it was found that, in the present invention, it is more effective to increase the number of the same elements as the additive element of the core material serving as the contact base material and the additive element of the Ag alloy formed on the outer periphery.

[Effects of the Invention] According to the present invention described above, as shown in the table, the spot welding strength to the base material is also excellent, and a very excellent effect is exhibited in the contact switching test using an actual machine.

Continuation of front page (56) References JP-A-63-149341 (JP, A) JP-A-64-65203 (JP, A) JP-A 1-268831 (JP, A) JP-A 1-108331 (JP) JP-A-58-110639 (JP, A) JP-A-58-107440 (JP, A) JP-A-59-215443 (JP, A) JP-A-60-248806 (JP, A) 52-33067 (JP, A) JP-A-53-88954 (JP, A) JP-A-58-144445 (JP, A) JP-A-58-104141 (JP, A) JP-A-3-219031 (JP, A) A) (58) Field surveyed (Int. Cl. ⁶ , DB name) H01H 1/00-1/04 C22C 5/06

Claims (2)

(57) [Claims] (1) 0.05 to 6 wt% of Sb oxide in Ag;
~ 2 wt% Te oxide and 0.05-5 wt% Sn, In, Cu, Mn
The core material is a material in which each oxide of
Ag alloy layer formed by adding at least two of the elements Sb, Te, Sn, In, Cu, and Mn in Ag in the range of 0.01 to 2 wt%, and occupying the entire cross-sectional area of the composite material A composite material for electric contacts, wherein the area ratio of the Ag alloy layer is 5 to 40%. 2. A method according to claim 1, wherein 0.05 to 6% by weight of Sb oxide is contained in Ag,
~ 2 wt% Te oxide and 0.05-5 wt% Sn, In, Cu, Mn
A core material is prepared by dispersing 0.01 to 1 wt% of each oxide and one or both oxides of Fe or Ni, and Sb, Te, Sn, In, Cu, Mn of Ag in the outer periphery thereof. 2 of each element
For an electrical contact, characterized in that an Ag alloy layer containing at least seeds added in a range of 0.01 to 2 wt% is formed, and an area ratio of the Ag alloy layer to the entire cross-sectional area of the composite material is 5 to 40%. Composite materials.