JPH0689422B2 - Electrical contact material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention provides Ag- which has high mechanical strength and is excellent in welding resistance.
The present invention relates to a Ni-based alloy electrical contact material.

[Conventional technology]

Conventionally, various materials have been used as electric contact materials, but among them, Ag-Ni contacts are widely used in place of Ag because of their low contact resistance and low consumption.

In addition, since Ag-Ni is easy to process and spot weld, it is possible to automate the work of sticking it to a base material, etc., resulting in low assembly costs and stable quality.

[Problems to be solved by the invention]

However, Ag-Ni has a problem that its use range is limited to a relatively small current region because its mechanical strength is small and welding resistance is inferior as compared with Ag-oxide systems such as Ag-Cdo.

In recent years, devices and equipment have been aiming for weight reduction, downsizing, and capacity increase, but also from this point, there is a problem that the Ag-Ni-based welding resistance is poor.

As a method of solving these problems, we are trying to improve the characteristics by adding various metal oxides, nitrides, carbides, borides, etc. to the Ag-Ni alloy. Ag-Ni alloys are produced by powder sintering because there is almost no solid solubility between Ag and Ni. The above-mentioned attempts have been made with the addition of metal oxides, nitrides, carbides and borides. The size and dispersion of the particles are problematic, and additive particles are always present on the contact surface. If the particles are coarse or in a poorly dispersed state, the contact resistance becomes extremely unstable, or the contact resistance becomes high, impairing the stable contact property that is the original feature of Ag-Ni system, and the welding resistance due to temperature rise etc. Will be lowered.

Another problem is that the workability and spot weldability, which are the characteristics of Ag-Ni alloys, are impeded by the mixture of various additives, making it impossible to build an automated line.

An object of the present invention is to improve the mechanical strength and the welding resistance without deteriorating the workability and spot weldability, which are the characteristics of Ag-Ni alloys, and to extend the range of current used.

[Means for solving problems]

The present invention achieves the above-mentioned object. Ni powder containing 5 wt% to 25 wt% of Ni and at least one of P, Cu and Ge is added to 0.1
A diffusion alloy layer of at least one or more of P, Cu, Ge and Ni powder is formed on the outer periphery of Ni powder in the alloy structure of the alloy formed by mixing and sintering Ag alloy powder containing 5 wt% to 5 wt% It is characterized by being.

[Action]

According to the present invention, 0.1 wt% to 5 wt% of at least one metal selected from P, Cu, Ge is dissolved with Ag to form alloy powder by the melt spraying method (atomizing), and after mixed molding The alloy powder and Ni powder of 5 to 25% by weight are sufficiently heated and sintered at a predetermined temperature.

After that, normal processing is performed to disperse Ni in the Ag alloy matrix.

At this time, it is important to sufficiently diffuse the solute metal P, Cu, Ge and Ni grains in the matrix by sintering and heating after forming, and it is necessary to simply disperse Ni in a simple Ag matrix. The mechanical strength is improved and the welding resistance is significantly improved in comparison with that of Ag.Ni, and Ag-Ni forms a diffusion alloy layer on the outer peripheral portion of the Ni grain through an element that forms a solid solution with Ni. Can be improved.

〔Example〕

 Examples of the present invention will be described below.

98Ag-2Ge, 98Ag-2Cu, 97.95Ag-2Cu-0.05P, 97Ag-2Ge
-1Cu, 97.97Ag-1Ge-1Cu-0.03P alloy with a composition ratio is made into powder by an atomizing device and sieved to powder of 300 mesh or less.

Each of these alloy powders contains 85% by weight and 300% of Ni15% by weight.
The powder below the mesh is mixed using a V-type mixer, and 85 (Ag-2Ge) -Ni, 85 (Ag-2Cu) -Ni, 85 (Ag-2Cu-0.05p) -Ni, 85 (Ag It was prepared so that each composition would be −2Ge-1Cu) -Ni, 85 (Ag-1Ge-1Cu-0.03P) -Ni.

These are molded to a diameter of 50φ and a length of 120 mm at a pressure of 2.5 t / cm ² , and the molding material is heated and sintered in a non-oxidizing atmosphere at a predetermined temperature for a predetermined time to obtain a billet.

These are heated in a non-oxidizing atmosphere and the diameter is 10φ with an extruder.
And a wire rod having a diameter of 6φ using a wire drawing machine.

A revetted contact material having a diameter of 6φ is formed from the wire.

The contact resistance, the amount of wear, and the number of weldings of the rivet-shaped contact material produced as described above were measured under the following conditions using an ASTM tester. The results are compared with Table 1.

Incidentally, 85Ag-Ni is listed as a conventional example.

[Effects of the Invention] As described above, the present invention provides at least one of P, Cu and Ge.
The material strength is improved by decomposing Ni into the base material alloyed with Ag in the addition amount of the seed within the predetermined range and forming the diffusion alloy layer on the outer peripheral portion.

In addition, by attaching P, Cu, and Ge, which have a relatively high oxygen affinity, these oxides are easily generated at the contact interface of the contact, and the sublimation of this oxide causes a cooling phenomenon of the arc and prevents welding. And wear resistance are improved.

From the above, the effect can be expected as an improvement of the characteristics of the conventional Ag-Ni-based electrical contact material.

Claims (1)

[Claims] 1. Ni powder containing 5% to 25% by weight of Ni and P, Cu, G
At least one or more of P, Cu, Ge and Ni powder are formed on the outer periphery of the Ni powder in the alloy structure of the alloy obtained by mixing and sintering Ag alloy powder containing at least one of e of 0.1 to 5% by weight. An electrical contact material, characterized in that a diffusion alloy layer with is formed.