KR830001153B1 - Ag-metal oxides electrical contact material contuining internally oxidized induim oxides and/or tin oxides - Google Patents

Abstract

An electrical contact material obtained through internally oxidizing a silver alloy which is the solid solution with 3 to 11 weight percent of tin and other solute metal element(s). The alloy material is improved of its contact resistance by diffusing into the silver matrix 0.1 to 5 weight percent of metals having a decomposition and sublimation temperature lower than the melting point of silver and then by internally oxidizing the material.

Description

Silver oxide electrical contact material including indium oxide and tin oxide of internal oxidation

The present invention relates to a silver oxide electrical contact material comprising indium oxide and tin oxide of internal oxidation.

In particular, the present invention relates to silver oxide electrical contact materials having improved electrical properties since the interior includes indium oxide and tin oxide oxidized. As an example, the durability is excellent when referring to the silver-tin oxide-indium oxide electrical contact materials shown in US Pat. Nos. 3,874,941 and 3,933,485. In addition, the silver-tin oxide-bismuth oxide electrical contact material shown in US Pat. No. 3,933,486 also has excellent durability as described above.

However, since tin oxide and indium oxide have a sublimation temperature much higher than the melting point of silver, they are not satisfactory in terms of contact resistance, especially when used under low current.

In the case of a silver-tin oxide-indium oxide contact material, when the weight ratio of tin (Sn) and indium (In) is 3-11% and 1-3%, respectively, and the total weight ratio of these coagulated metals is 4-16%. Its durability is satisfactory.

When the amount of tin is less than 3% (unless otherwise stated, the forward proportions represent weight ratios), the durability of the contact material is actually inadequate, whereas more than 11% tin cannot form silver and solid solutions. Can not use

It can be seen that when internally oxidizing an alloy containing tin in the above weight ratio, 1-13% of indium can successfully disperse and condense tin in the matrix.

In addition, the total weight ratio of the coagulated metals, ie 4-16%, is the range in which they can be internally oxidized.

In the case of a silver-tin oxide-bismuth oxide contact material, excellent durability can be obtained in practical use when tin is in the range of 3-11% and bismuth is in the range of 0.01-2%.

This limited amount can be explained for the same reasons as described with respect to the silver-tin oxide-indium oxide alloy contact material.

In order to obtain a better contact resistance of the above-described type of silver oxide contact material containing tin oxide, the inventors have found that zinc (Zn), cadmium (Cd) and calcium (Ca) have a sublimation temperature lower than silver (oxide) in the contact material. We also considered the addition of metals such as purple.

However, since the silver (Ag) alloy already contains the maximum amount of solute metals that can be internally oxidized, internal oxidation is impossible by directly adding auxiliary metals such as zinc, cadmium and calcium to the silver alloy.

In view of the above, the object of the present invention is not only to include a very durable metal oxide in the maximum amount capable of internal oxidation, but also to include a silver alloy electric material including auxiliary metal oxides having a temperature rise temperature near or lower than the melting point of silver. By manufacturing the contact material, the contact resistance of the silver alloy electrical contact material is improved.

Such a silver alloy electrical contact material is an alloy of silver matrix containing 3-11% tin and 1-13% indium or a silver matrix containing 3-11% tin and 0.01-2% bismuth according to the present invention. After the alloy is internally oxidized, one or more auxiliary solute metals such as zinc (Zn), antimony (Sb), and cadmium (Cd) are plated and diffused on the internally oxidized alloy material and alloyed with the internal oxidation alloy material described above. The obtained material can be obtained by internal oxidation.

The working principle of the above two-step internal oxidation treatment that can include another oxidized solute metal in the alloy of silver oxide which already contains the maximum amount of coagulated metal capable of internal oxidation is as follows.

When the alloy was first internally oxidized, the silver matrix of the alloy became pure silver with a 50% weld ratio of the total volume of the internal oxidation alloy, and the secondary solute metal could reach the pure silver and solid solution described above. It can be internally oxidized without any adverse effect on the metal oxides already condensed in the silver matrix in the first internal oxidation step.

It has also been found that adding 0.1-5% of one or more metals such as zinc (Zn), cadmium (Cd) and calcium to improve the contact resistance of the silver-tin oxide electrical contact materials described above is sufficient.

In addition to zinc (Zn), cadmium (Cd) and calcium (Ca), antimony (Sb), lead (Pb), manganese (Mn), magnesium (Mg), as well as other materials that can diffuse into the silver matrix near the melting point of silver Solute metals may also be used with zinc, cadmium and calcium.

In addition, by adding tin (Sn) and indium (In) as auxiliary solute metals with one or more solute metals having a decomposition and sublimation temperature lower than the melting point of silver, the alloy contact material of the present invention not only has a high contact resistance but also a high durability. It can be seen that it can have.

Also included are indium alloys of tin (1-13%) and silver (3-11%) and bismuth alloys of tin (0.01-2%) and silver (3-10%).

At this time, less than 21% of the solute metal can decompose crystals, prevent the formation of coarse crystals, and increase the ratio of the solute metal to silver to prevent gaps in internal oxidation. , Molybdenum, zirconium and calcium.

Next, the conventional technologies will be described.

For example, in U.S. Patent No. 3,989,516, at least one of three preservative solute metal elements of zinc, cadmium, and calcium is diffused in order to have the property of decomposing and subliming at a temperature equal to or lower than the melting point of silver. There is no mention of electrical contact materials having an alloy matrix which has been condensed and internally oxidized. Obviously, in addition to the above-mentioned technique, U.S. Patent No. 3,811,876 makes no mention of the contact material of the present invention in which the auxiliary solute metal is diffusely condensed into an internally oxidized alloy matrix.

An excellent result of the present invention is to increase the electrical contact resistance of the material without any adverse effect on the metal oxide already condensed on the alloy matrix by the first internal oxidation process.

Next, the present invention will be described in detail with reference to Examples.

Example 1

(1) Ag-Sn (3%)-In (1%) (2) Ag-Sn (3%)-In (13%)

(3) Ag-Sn (8%)-In (3%)-Ni (0.2%)

The alloys were melted and dropped into a drop of water to form spheres of 1 mm diameter.

These spheres were internally oxidized for 12 hours at a temperature of 700 ° C. under 10 atmospheres of oxidizing atmosphere.

The surface was washed with 5% nitric acid solution. On these spheres

Zn, Cd, Ca, Zn-Sb, Zn-Cd, Zn-Ca, Sb-Cd, Sb-Ca, Cd-Ca, Zn-Sb-Cd, Zn-Sb-Ca, Sb-Cd-Ca, Ca- Cd-Zn or Zn-Sb-Cd-Ca was plated to a thickness of 0.5 mm.

These spheres were thermally pressurized at 400 ° C. to form large bundles of 50 mm diameter and 150 mm length.

This bundle was heated at a temperature of 700 ° C. to draw a line with a diameter of 3 mm.

This wire was internally oxidized at a temperature of 700 ° C. for 5 hours under 1 atmosphere of oxygen.

These wires were cut into disks with a diameter of 5 mm and 1 mm, and then cold-contacted with nail-shaped copper having a head of 5 mm diameter and thickness and a body having a diameter and a length of 3 mm.

The disk-like internal oxidation contact material thus obtained is as follows.

(a) Ag-Sn (3%)-In (1%)-Zn (2%)

(b) Ag-Sn (3%)-In (13%)-Cd (5%)

(C) Ag-Sn (8%)-In (3%)-Ni (0.2%)-Ca (0.1%)

(d) Ag-Sn (3%)-In (1%)-Zn (1%)-Sb (1%)

(e) Ag-Sn (3%)-In (13%)-Zn (1%)-Ca (0.1%)

(f) Ag-Sn (8%)-In (3%)-Ni (0.2%)-Sb (1%)-Cd (3%)

(g) Ag-Sn (3%)-In (1%)-Zn (2%)-Sb (1%)-Ca (0.1%)

(h) Ag-Sn (3%)-In (13%)-Cd (1%)-Ca (0.1%)

(i) Ag-Sn (8%)-In (3%)-Ni (0.2) -Zn (0.1%)-Sb (0.1%)-Cd (3%)

(j) Ag-Sn (3%)-In (1%)-Zn (1%)-Sb (1%)-Ca (0.1%)

(k) Ag-Sn (3%)-In (13%)-Ca (0.1%)-Cd (2%)-Zn (1%)

(i) Ag-Sn (8%)-In (3%)-Fe- (0.01%)-Zn (0.1%)-Sb (0.1%)-Cd (1%)-Ca (0 (01%)

Example 2

(4) Ag-Sn (3%)-Bi (0.01%)

(5) Ag-Sn (12%)-Bi (0.2%)

(6) Ag-Sn (8.5%)-Bi (0.1%)-Ni (0.5%)

The above alloys were obtained in the following internal oxidation alloys in the same manner as in Example 1.

(m) Ag-Sn (3%)-Bi (0.01%)-Zn (0.1%)

(n) Ag-Sn (12%)-Bi (0.2%)-Sb (2%)-2n (1%)

(o) Ag-Sn (8.5%)-Bi (0.1%)-Ni (9.1%)-Cd (5%)

(p) Ag-Sn (8.5%)-Bi (0.1%)-Ca (1%)

(q) Ag-Sn (8.5%)-Bi (0.1%)-Pb (1%)-Zn (1%)

(r) Ag-Sn (8.5%)-Bi (0.1%)-Mn (0.5%)-In (1%)

(s) Ag-Sn (8.5%)-Bi (0.1%)-Mg (0.5%)-Cd (3%)

(t) Ag-Sn (8.5%)-Bi (0.1%)-Zn (0.1%)-Cd (4%)

The above assignments (a-t) were tested for their contact resistance as compared to the (1)-(6) alloys (see Table 1).

The test results are shown in Table 1 and the test conditions are as follows.

Test (load: Ac 220V, 13.5A, pf = 50% contact force: 100g) The voltage drop (m) was measured using DC 6V, 1A as specified in ASTM-30.

From the above result, it is clear that the electrical contact material by this invention improved the contact resistance.

TABLE 1

As a specific method of the present invention, the alloys of (1)-(6) described above were melted and plated with silver to form a plate having a thickness of 2 mm.

These plates were pressed to obtain a contact material having a diameter of 6 mm and a thickness of 2 mm.

These contact materials were internally oxidized at a temperature of 700 DEG C under 3 atmospheres of oxygen.

These surfaces are Zn, Cd, Ca, Zn-Sb, Zn-Cd, Zn-Ca, Sb-Cd, Sb-Ca, Cd-Ca, Zn-Sb-Cd, Zn-Sb-Ca, Sb-Cd- It was plated with Ca, Ca-Cd-Zn or Zn-Sb-Cd-Ca layer for internal oxidation.

In this way one or more metal elements diffuse into the silver matrix of the contact material and condense into the secondary oxide alloy.

The contact material thus obtained improved the contact resistance like the (a- (t) alloy described above.

Such contact materials are also within the scope of the present invention and include the electrical contact materials mentioned in the specification and claims.

Claims (1)

An electrical contact agent having improved contact resistance obtained by internal oxidation of an alloy of silver and soluble metals, wherein the electrical alloy material contains 3-11% by weight of the silver base metal of the first major soluble metal consisting of tin, At least one other major soluble metal selected from the group consisting of mismuth is 0.1-5 weight selected from the group consisting of zinc, cadmium and calcium, with a total weight percent of the electrical major soluble metals being 3.01-16%. % Of at least one additional material of the cladding metal, which is dispersed in the internally oxidized alloy base metal and then internally oxidized, each additional metal material condensing in the alloy base metal, near or above the melting point of silver. Contains internal oxides indium oxide and tin oxide with improved contact resistance with decomposition sublimation at low temperatures Silver oxide is in electrical contact material.