JPS5884951A - Electrical contact material - Google Patents

Abstract

PURPOSE:To obtain an electrical contact material having superior characteristics by dispersing specified amounts of Bi2O3 and ZnO in an Ag-Cu alloy matrix or by further dispersing an oxide such as In2O3. CONSTITUTION:Bi and Zn are added to Ag so that 0.5-3wt% Bi and 0.5-5wt% Zn are contained finally, or 0.5-2wt% In is further added. They are melted and sprayed with compressed gaseous nitrogen to form alloy powder. By heating the powder in an oxidizing atmosphere. Bi, Zn and In in the alloy are oxidized selectively and preferentially to Bi2O3, ZnO and In2O3. Ag-Cu alloy powder contg. Cu in Ag so that 1-10wt% Cu is contained finally is prepared and mixed with said Ag powder contg. the dispersed oxides, and the mixture is molded and sintered to manufacture an electrical contact material contg. Bi2O3, ZnO and In2O3 dispersed in the Ag-Cu matrix contg. Cu dispersed in the Ag matrix.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a composite contact material in which metal oxides are dispersed in a MQ alloy matrix, and the present invention relates to a composite contact material having a metal oxide dispersed in a MQ alloy matrix. The present invention provides an electrical contact material suitable for use in slide switches that open and close.

Muq-O is a composite contact material using metal oxides.
ClO contact materials are widely used, and recently 5g
8n02-based materials have also come into use.

However, in recent years, various switches for electronic devices have been required to be easier to operate and more compact in order to improve contact reliability in accordance with safety regulations and to improve ease of use. A trend has been seen in which the load is switched on and off to the extent of several centimeters. As a result, spring materials 1, which have been widely used as contact materials for slide switches, such as υn grown copper (Sn7-9% by weight, Po, 03-0.35
In the case of a material in which Ag is laminated to a thickness of 2 to 10 μm to (% by weight, balance Cu), sufficient life characteristics cannot be obtained due to wear due to arcing.

On the other hand, for arc consumption, the above-mentioned Muq-CdO.

Mug-5n02 type material is desirable, but it has problems with mechanical sliding properties, and when used as a material for slide switches, it is stretched to a spring material and rolled to the desired shape. Although it was processed to a certain thickness, this point was found to be difficult.

The present invention has been made in view of the above points, and basically, Bi2O is added to a matrix made of a 5g-Cu alloy.
The present applicant has already dispersed oxides such as znO2In2OS in addition to Bi2O5 in a mucous matrix to improve the characteristics of slide switches by providing a material in which oxides having , as the main components, are dispersed. He suggested the material. Although these materials exhibit excellent properties in terms of welding resistance and arc wear similar to MuG-CCTO, they do not necessarily exhibit satisfactory sliding properties. Furthermore, it is not a material that can be easily stretched to a spring material. However, on the other hand, since it is composed of an oxide with a lower vapor pressure than CdO, there are fewer defects in the bonding layer during bonding, or Bi2 has a low hardness as an oxide.
Since it contains O, 5, and ZnO, it has advantages such as relatively good workability and a certain degree of spreadability. As a result of the study on improvement measures for spring materials, tension adjustment measures for spring materials, and maintenance of arc characteristics necessary and sufficient as a material for slide switches, O was added to the Mug-Cu alloy matrix, and Bi2O was added to the Mug-Cu alloy matrix.
5 and ZnO or further In2O
It has been found that the desired object can be achieved by a material dispersed with the addition of 0.Next, the above-mentioned material according to the present invention will be described in detail.

The electrical contact material of the present invention contains oxides of Bi and Zn in a Mug-Cu alloy matrix.These oxides are composited into Bi! ZnA0 (however, "pV" is an integer).Then, depending on the composition ratio of old and Zn, B
It contains an oxide Bi2O3 of i or an oxide ZnO of Zn. Furthermore, in order to particularly reduce wear due to arcing, In2O5, an oxide of In, is added in addition to the above-mentioned oxides.

The electrical contact material of the present invention has the above-mentioned structure, and the content of these constituent materials is 1 to 10% by weight of O in the 5g-Cu alloy matrix, based on the weight ratio of all metal elements in the material. The oxide is Bio in metal equivalent value, 5 to 3% by weight,
Zn o,s ~ 5% by weight, and the balance is O
When adding In oxide, add 0.5 to the above value in terms of metal.
In the electrical contact material of the present invention, the Mg-Ou alloy constituting the Mq alloy matrix has good sliding properties for use in slide switches, as described above. It is effective in reducing mechanical wear, preventing adhesion, and reducing frictional force. In addition, when bonding to a spring material, a thermocompression bonding method is usually used, but oxide-containing materials have a weak bonding force, and the adhesive layer often peels off during the subsequent rolling process.

Here, the bonding metal layer is an In layer or an In layer and C
The U layer is inserted between the contact material of the present invention and the spring material, and the bonding metal layer is liquid-phase diffused by the eutectic melting of Mug-Cu-In that occurs between the IJ alloy and the IJ alloy of the present invention, thereby eliminating defects. Obtaining less adhesive layer. Muq alloy ma) C in IJ
The lower limit of the amount of u added is determined by the minimum amount to bring out the above effects. On the other hand, its upper limit is limited by mechanical processability or contact resistance characteristics.

Next, the oxide contained in the electrical contact material of the present invention will be explained. The main oxides contained are Bi and Z.
It is an oxide of n. These oxides are, for example, B14B
Although it forms some complex oxides such as Zn+Oys, most of it exists in a single form.

The melting point of the composite oxide decreases to around 760°C. As will be described later, this material is partially produced by a sintering method, and at this time it exhibits a function of increasing the sinterability between powder particles.

On the other hand, the Bi2O5 oxide that exists alone becomes γ-Bi2O3 when it contains a small amount of other oxides, and its melting point rises, making it a material with a sublimation point around 100°C, which is suitable for welding of contacts. It shows the improvement effect.

However, B i 203 alone does not provide sufficient resistance to arc wear, so ZnO is required to be added. If the shear arc consumption is to be reduced, I
Addition of n 205 oxide is desired.

In the Mug-Ou alloy matrix, the above Bi, Zn
.

As a method of dispersing In oxide, Bi is added to the muq.
, Zn, and In are added, and this is heated in an oxidizing atmosphere to form Bi, Zn, and In.
We use the so-called internal oxidation method, which selectively oxidizes O, to form an internal oxidation alloy powder, add separately prepared Muq-Ou powder, mix homogeneously, and then shape and sinter to form Ou in the matrix. A Mug-Cu alloy matrix is obtained by diffusion, and an oxide is dispersed therein.

In materials produced by such methods and configurations,
The composition ratios of the metal elements to be converted into oxides were determined under the conditions described above, and were Bi and Zn.

Each minimum amount of In is the lower limit at which the addition effect is recognized for the intended use of the material according to the present invention, and each maximum amount is a rolling or This is an amount that is subject to limitations in terms of workability such as bending and punching for slide switch contacts.

The electrical contact material of the present invention described above will be explained in more detail based on Examples.

Mug, Cu, Bi, Zn according to the composition of the invention.

A total of 500 g of In is weighed. Ag is divided into an amount that can contain the same amounts of BL, Zn, and In, which are converted as oxides, and an alloy with Cu for the remaining matrix. For example, in the case of the material for the movable contact of sample shop 6 shown in the table, the matrix is a Mug-Ou alloy containing 5% by weight of Cu, which contains 0.5% by weight of Bi and 1.5% by weight in terms of metal. %Z
n and 2% by weight of rn, the respective weighing values are Bi 2.5 (J, Zn 7.5 g, In for oxide 10 g, Cu for matrix 26 q, Mug 456 g, totaling 5009. .Here, 465g of mug
Of this, 260q was separated and B12. s g,
Add and dissolve 7.5 g of Zn and 10q of In,
In order to produce a powder for an internally oxidized alloy, the powder is pulverized using a molten metal spraying device using pressurized nitrogen gas to obtain an alloy powder of approximately 60 to 326 mesh. This powder is heat-treated in the air at a temperature of 700'C for 60 hours to form an internally oxidized alloy powder in which Bi, Zn, In, etc. are selectively oxidized in the muq matrix. On the other hand, the remaining portion 205q of Muq and Cu 25 <i for matrix are similarly melted and then turned into Mug-Ou alloy powder by a molten metal spraying device. The above is 6
Although the above sample was described as an example, the process is roughly the same for other samples as well. After these powders were mixed homogeneously, 3
Q rn Loaded into a cylinder with a diameter of 7'm, 4 tons/cd
It is molded with a pressure of The molded billet is sintered at 650°C to 800°C in a nitrogen gas atmosphere. In addition,
In this case, the matrix portion will flow out, so consideration should be given to the temperature increase gradient so that O diffuses into the internal oxidized powder matrix. The billet sintered in this way is then molded again at 450°C and 8) m/tJ, and then subjected to sintering heat treatment under the same conditions as before.

This sintered body is produced by warm extrusion at 550 to eoo°C to have a diameter of 30 m/m and a width of 20 m/m.

It is processed into a plate shape with a thickness of 3m/m2. Further, after cold rolling to a thickness of 1 m/m, the surface is polished and cleaned using Scotchbrite.

On the other hand, the spring material is 9 m/m thick and 30 m wide.
An 8 wt. % Sn phosphor bronze plate of 8 wt. Further, 10 to 20 μm of In plating is applied on the Cju plating.

Note that Cu plating can be omitted if the Cu composition of the matrix is 8% or more. And the 1 m/r that was processed earlier! L
Layer a thick oxide-19 alloy plate on the In plated surface,
After adhering with a heat-resistant jig, 65°C in a nitrogen gas atmosphere.
Heat treatment is performed at 0°C to 760°C for 1 hour and pressure bonding is performed. At this time C
Each of the plating layers of u and In undergoes liquid phase diffusion, but the plating layers of Mug-Cu
It exhibits a synergistic effect with CU in the matrix, resulting in a bonded state with fewer defects. Finally, this bonding material is processed to a thickness of 70 μm by repeating annealing and rolling.

The material obtained as described above was molded into a movable contact of a slide switch, and its characteristics were evaluated. In addition, the fixed side contact of the test slide switch is as follows:
A 0.6m thick, 4mm brass plate with 2μ thick matting was used, and contact lubricant made from synthetic oil, which is normally used for slide switches, was applied to the mating surface. . As samples for comparison of characteristics, we prepared a phosphor bronze contact with a total thickness of 70μ, in which the movable contact was laminated with muq of thickness Tμ, and a slide switch using the same material and lubricant as above for the fixed contact.

The switch was evaluated by opening and closing a load circuit with a capacitor load of 30V, steady state of 3V, and inrush of 30V 20,000 times, and then observing the contact resistance and the state of contact wear. The results are shown in the thorn table (blank below). As is clear from the results in the table, the electrical contact material according to the present invention exhibits practically sufficient characteristics even after the operation test. In addition, less consumption and wear of materials leads to improved insulation between switch contacts, which is favorable from a safety standpoint.

On the other hand, in the case of MQ single material, which is currently widely used, the phosphor bronze surface of the spring material is exposed due to arc consumption, as shown in sample &8, and in some cases, holes are formed on the phosphor bronze surface. Some did.

As explained above, the electrical contact material of the present invention is intended to make it possible to extend the switching load of a slide switch to the arc generation region, and its practical value is extremely high.

Claims (1)

[Claims] (1) In a MQ alloy matrix containing 1 to 10% by weight of O and the remainder being MQ, 0.5 to 3% by weight of Bi and 0.5 to 3% of Zn are added in terms of metal oxides. An electrical contact material comprising 6% by weight. @) Muq alloy containing 1 to 10% by weight of Ou and the remainder being Muq) In an IJ box, the metal oxide is converted to a metal equivalent value, Bi is 0.6 to 3% by weight, and Zn is added to 3.0% by weight. An electrical contact material comprising 5 to 6% by weight of In and 0.6 to 2% by weight of In.